Not Even Wrong

[selfAdjoint]

Peter Woit has a blog! (http://www.math.columbia.edu/~woit/blog/) . Much good stuff, not too hard on string theory, plus check out his links.

[marcus]

Originally posted by selfAdjoint
Peter Woit has a blog! (http://www.math.columbia.edu/~woit/blog/) . Much good stuff, not too hard on string theory, plus check out his links.

Fascinating. Very interested by his summary of the points in
David Gross talk.

will check out his links after lunch.

[selfAdjoint]

Note that in his post "The Holy Grail of Physics" Woit mentions Jackiw. Jackiw has a retrospective paper, http://arxiv.org/abs/physics/0403109 for the 50th anniversay of Yang-Mills, in which he discusses the helicity puzzles that Woit speaks of.

[marcus]

Woit's March 19, 2004 blog was especially informative. As senior faculty at Columbia, in mathematical physics---the guy teaching grad students their QFT and Representation Theory---his judgements on the past 20 years progress in Particle Physics are especially crisp and authoritative.

--------Woit's comment on David Gross talk----
Gross's talk contained the usual tendentious pro-string theory points, here's a few of them with commentary:

1. " String theory is in a period like that of 1913-1925, it's like the Bohr model, we're waiting for the analog of Heisenberg's or Schrodinger's breakthroughs"

The problem with this is that the Bohr model was actually predictive, for instance it predicted a lot about atomic spectra that could be experimentally checked. There clearly was something right about the Bohr model, there is no good evidence there is something right about string theory.
...
...
4. "String theory is a consistent, finite quantum theory of gravity"

Simply not true. Peturbative string theory is a divergent expansion, non-perturbative definitions don't work for four large flat dimensions, rest small.

5. "String theory inspired brane-world scenarios, although I don't really believe these"

Why would you think that an argument in a theory's favor was that it inspired some clearly wrong models that you don't believe and that don't predict anything?

--------end quote-------

[jeff]

Originally posted by marcus
As senior faculty at Columbia...his judgements on the past 20 years progress in Particle Physics are especially crisp and authoritative.

Peter woit is just an instructor, not a professor. If you search the arXiv's, you'll find two papers by him, with one of them being a five page polemic on string theory in the subject class of 'physics and society' and with not a single reference. If you want to learn about string theory, this isn't the place to start.

[marcus]

So we have on good authority that string theory is not
a viable quantum theory of gravity.

Since it has been hugely hyped as exactly that, it's time for major debunking.

----at the end of Woit's March 19 report on Gross talk------

...I noticed that two string theory postdocs I know were in the audience. They've both told me that they think the subject is at a point of crisis and they are thinking of quitting. I don't think anything Gross said was likely to encourage them to continue.
-----------end quote---------

[marcus]

I may be mistaken about Woit's standing in the math and physics departments at Columbia. I am remembering from some months back when I happened to visit his website and saw the graduate level courses he was teaching.

Would be glad for fuller information. In which department? Mathematics or Physics?

Answered my own question!
The math department at Columbia has this link
http://www.math.columbia.edu/people/faculty.phtml

It shows that Peter Woit got his PhD in 1985 from Princeton.

So he was probably born around 1960 and must be in his Forties.

In some sense senior---I would guess tenured faculty. No doubt we will learn more.

[Haelfix]

Woit is a smart guy, I've met him before. He's echoing publically what we often hear in private conversations with mathematicians, who work on physics.

Theres a huge literature that is often overlooked by physicists, (aside from a select few like Witten) that deals with QFT/string theory etc using modern approaches and topics that are just recently becoming rigorous in mathematics.

Advances in K theory, infinite dimensional lie groups, etc etc

The fact of the matter is, its perfectly normal to expect skepticism from mathematicians, since the tools to treat String theory in a manner that makes sense to them doesn't exist yet. Its no coincidence physicists say its a 21st century theory that happened to be stumbled upon in the 20th century.

AFAICS, Woit's main beef is that the lvl of funding is so lopsided and other lines of inquiry seem to be supressed monetarily in favor of the orthodoxy.

[marcus]

Originally posted by jeff
Peter woit is just an instructor, not a professor. If you search the arXiv's, you'll find two papers by him, with one of them being a five page polemic on string theory in the subject class of 'physics and society' and with not a single reference. If you want to learn about string theory, this isn't the place to start.

have to see about whether a professor or instructor
instructor was usually a title for young faculty
not yet on tenure track. I suspect that Columbia math dept
has no instructors on the faculty---full-time positions
would most likely be all assoc. prof. or asst. prof. or full professor. But you could be right! No doubt we will see in time.

[marcus]

Originally posted by Haelfix
Woit is a smart guy, I've met him before...

Haelfix do you happen to know if Woit has made professor.
We have someone here saying he is "just an instructor" which
would seem bizarre given the other signs of senior faculty standing.

[rick1138]

Here is a link to Gross's talk:

http://online.kitp.ucsb.edu/online/mt01teach/gross/

[lethe]

Originally posted by marcus
Haelfix do you happen to know if Woit has made professor.
We have someone here saying he is "just an instructor" which
would seem bizarre given the other signs of senior faculty standing.

which "other signs" were you talking about? the fact that he teaches classes? i know lots of people who teach, and yet are not professors.

anyway, you can see from the math department website that he is a "Director of Instruction", and not a Professor (associate or otherwise)

i guess you just chose not to see that when you were looking at it.

[Haelfix]

No clue what position he holds, other than that he works at Columbia, not that it matters.

I do know that he knows what hes talking about w.r.t to field theory. But I don't think he is an expert on String theory, there are others at Columbia that know a lot more about that sort of stuff. Phong, Greene et al.

Typically mathematicians are introduced to String theory, when a physicist wanders over to their department when they're confused about something and nead expertise in some archaic form. The mathematician then has the distinct horror of trying to figure out a problem, without even knowing where its coming from.

The conversation will go something like
Mathematician 'whats that measure'
Physicist 'its undefined'
Mathematician 'what?!?'
Physicist 'ignore it, just tell me what Hodge theory says about this right here'
...

I exagerate, but thats often how things can go. The physicist will go off pleased, and the math guy left wondering about their sanity.

[selfAdjoint]

Originally posted by marcus
have to see about whether a professor or instructor
instructor was usually a title for young faculty
not yet on tenure track. I suspect that Columbia math dept
has no instructors on the faculty---full-time positions
would most likely be all assoc. prof. or asst. prof. or full professor. But you could be right! No doubt we will see in time.

The university site has him as "Director of Instruction", which is surely not the same as "Instructor"? And he is the only individual included on that site who is not listed as some kind of Professor.

[marcus]

not to confuse Director of Instr (admin position some places comparable to Associate Dean) with Instructor (pre-tenure-track grade for young hires) for example
Greg Miller at U Washington
got his Phd in 1983
became Assistant Professor 1984
Associate Professor 1988
Professor 1995
made Director of Instruction 1998

be patient, more will probably come out about Woit's standing
he is a very interesting person
he watches theoretical physics closely
and at Columbia he teaches the graduate level courses in
Lie Groups and Representations
Quantum Field Theory
he has ideas about what direction EXPERIMENTAL hep should take
he is not exactly Haelfix's model of a periferal mathematician
shaking his head in disbelief at the vagaries of physicists
he strikes me more as a centrally knowledgeable type of math/physicist.

in any case I do not accept the dismissive estimate that Woit is "just an instructor" and I am happy to wait and learn more about this very interesting person

I do not know that he is a professor or not a professor and I am not convinced that this matters, but he seems senior to me---resepected, with some adminstrative function in the department---in his 40s---very smart----with a sense of history and a complex perspective

[marcus]

Originally posted by Haelfix
Woit is a smart guy, I've met him before.
...
AFAICS, Woit's main beef is that the lvl of funding is so lopsided and other lines of inquiry seem to be supressed monetarily in favor of the orthodoxy.

Haelfix I really like your sketch of the encounter between the mathematician and physicist. It is majorly true to life.
But I think Woit's beef is more interesting than that.

An important part of it is that the mathematics of string theory is not very interesting (or forward-looking) mathematics
and he points to more interesting directions in math/physics
where theoreticians could be going if they were not so
bogged in string

he is highly critical of the bromide about "a bit of 21st century that happened to plop down prematurely in the 20th century" or whatever Witten's inspired prophesy was

You have got me interested now. So I will go back to Woit's essay and see better what his beef is
I know it is about more than lopsided money, but I want to be refreshed as to details.

[jeff]

Originally posted by Haelfix
No clue what position he holds, other than that he works at Columbia, not that it matters.

I think it does matter since

(1) It's his ideas that are the subject of this thread.

(2) These ideas are by his own admission polemical.

(3) Marcus is trying to convince members that woit is more credible and more of an authority than he actually is.

Originally posted by Haelfix
But I don't think he is an expert on String theory

Correct. So how seriously should woit be taken? Well, he isn't a researcher, as is clear from the absence on his homepage (http://www.math.columbia.edu/~woit/) of any mention of, or links to any research papers. And notice, as I already mentioned, that even woit himself refers to his paper criticizing string theory as a polemic, which means that he himself wouldn't counsel anyone to take his paper - which by the way is listed under the subject class of 'physics and society' and not 'high energy theory' where research papers on strings are listed - as seriously as marcus does (especially since marcus is unable to understand physics at this level, as he's shown repeatedly. In greg's words, "marcus isn't very smart".)

Anyway, given that woit got his PhD in 1985, we can say that after 20 years he ended up as head TA.

[jeff]

Originally posted by marcus
An important part of it is that the mathematics of string theory is not very interesting (or forward-looking)

This isn't just you being mistaken marcus, this is you knowingly misrepresenting the facts, which from what I understand violates site guidelines.

[notevenwrong]

Wow, a whole internet thread about my academic qualifications!

I'd certainly prefer that people spend their time arguing over what I have to say than my qualifications for saying it, but here's an accurate outline of my peculiar academic career for those interested:

1979: B.A. and M.A. in physics, Harvard University. As an undergraduate spent one summer working on a particle physics experiment at SLAC.

1984: Ph. D. in theoretical physics, Princeton University, advisor Curtis Callan, thesis title "Topological Charge in Lattice Gauge Theory".

In my thesis I developed a workable way of calculating the topological charge of lattice gauge fields. This lead to joint work with collaborators including N. Seiberg at the Institute in Princeton and about seven published papers on the subject in the mid to late-eighties.

1984-87 Postdoc at the Stony Brook ITP
Got interested in spinor geometry,TQFT and representation theory, started talking to a lot of the mathematicians at Stony Brook

In 1987 it became clear to me that someone who didn't believe in string theory but wanted to apply mathematics to QFT didn't have much of a future in physics depts in the US. I spent 1987-88 as an unpaid visitor at the Harvard physics dept., earning a living teaching calculus in the Tufts math department.

1988-89 Postdoctoral fellowship at MSRI in Berkeley. Published a couple papers on spinor geometry and the standard model, TQFT and representation theory.

1989-1993 Assistant professor, math department, Columbia

At this point the "Director of Instruction" position became available in the math department. It is an unusual untenured but permanent position, with responsibilities that include making sure the dept computer system runs, teaching a course, participating in research activities of the department.. I've held that position for ten years.

I'm not a tenured full professor at Columbia and have never claimed to be. On the other hand, I've spent a lot of time learning mathematics, often by teaching it. I've taught many of our undergraduate courses and some of our graduate courses, including Representation theory and QFT for mathematicians.

So that's my weird academic background and status. make of it what you will.

My experience arguing with string theorists over the last few years has been that the ones that don't know me often spend their time refusing to respond to my arguments and personally attacking me instead. I'll let you decide what that says about how strong their case is.

[rick1138]

Exactly. Stick to the matter at hand. Truth or falsehood is independent of its vessel. It is logically fallacious to suggest otherwise.

[Urs]

Hi Peter Woit -

one question:

Did I understand you correctly that you reject the Matrix Models of string theory as a viable nonperturbative definition for the reason that they, as I think you said, don't give four large dimensions only?

I think I have read that somewhere on your weblog.

Could you provide more details on this argument? Do you claim that there are in principle no solutions of the MM that are realistic, or just that so far none have been found?

Have you looked at the papers which describe the search for a spontaneous compactification to d=4 in the IKKT model? There have apparently been several numerical computations, which kind of point in the right direction but are not conclusive yet, either way.

Thanks,
Urs

P.S.
Would you think that I am just another impolite graduate student if I said that you are notevenwrong? ;-)

Just kidding! :-) But more seriously: Why that particular pseudonym??

[pelastration]

Originally posted by notevenwrong
Wow, a whole internet thread about my academic qualifications!

....

So that's my weird academic background and status. make of it what you will.

My experience arguing with string theorists over the last few years has been that the ones that don't know me often spend their time refusing to respond to my arguments and personally attacking me instead. I'll let you decide what that says about how strong their case is.
Thanks Peter for clarification. It seems that for some posters here a title is the most important parameter for the IQ-level. ;-)

[jeff]

Hi Peter,

Originally posted by notevenwrong
...here's an accurate outline of my...academic career:

1979: B.A. and M.A. in physics, Harvard University. As an undergraduate spent one summer working on a particle physics experiment at SLAC.

1984: Ph. D. in theoretical physics, Princeton University, advisor Curtis Callan, thesis title "Topological Charge in Lattice Gauge Theory".

In my thesis I developed a workable way of calculating the topological charge of lattice gauge fields. This lead to joint work with collaborators including N. Seiberg at the Institute in Princeton and about seven published papers on the subject in the mid to late-eighties.

1984-87 Postdoc at the Stony Brook ITP
Got interested in spinor geometry,TQFT and representation theory, started talking to a lot of the mathematicians at Stony Brook

In 1987 it became clear to me that someone who didn't believe in string theory but wanted to apply mathematics to QFT didn't have much of a future in physics depts in the US. I spent 1987-88 as an unpaid visitor at the Harvard physics dept., earning a living teaching calculus in the Tufts math department.

1988-89 Postdoctoral fellowship at MSRI in Berkeley. Published a couple papers on spinor geometry and the standard model, TQFT and representation theory.

1989-1993 Assistant professor, math department, Columbia

At this point the "Director of Instruction" position became available in the math department. It is an unusual untenured but permanent position, with responsibilities that include making sure the dept computer system runs, teaching a course, participating in research activities of the department.. I've held that position for ten years...

Would you mind offering some advice on how to approach your polemic on string theory to people who campaign against stringy research without even attempting to understand it's basic ideas (or even those of QFT, as is true for some people here at PF)? It might even help if you could say something about what you feel the purpose of polemical writing is in general. Thanks.

[notevenwrong]

Originally posted by Urs
[B
Did I understand you correctly that you reject the Matrix Models of string theory as a viable nonperturbative definition for the reason that they, as I think you said, don't give four large dimensions only?

I think I have read that somewhere on your weblog.

Could you provide more details on this argument? Do you claim that there are in principle no solutions of the MM that are realistic, or just that so far none have been found?

Have you looked at the papers which describe the search for a spontaneous compactification to d=4 in the IKKT model? There have apparently been several numerical computations, which kind of point in the right direction but are not conclusive yet, either way.

Just kidding! :-) But more seriously: Why that particular pseudonym?? [/B]

Hi Urs,
I'm no expert on Matrix models, what I know about their status comes from reading review papers and arguing with Lubos Motl.
My understanding is that Matrix models conjecturally provide a non-perturbative definition of string theory, but only in flat eleven dimensional space or some other special backgrounds. As far as I know, no one knows how to properly formulate a version of the matrix model that works in the kind of background you want (four large flat dimensions times a small, highly curved 6/7 dimensional Calabi-Yau or G2 holonomy manifold). This is what I was referring to in the weblog.

As for "Not Even Wrong", it was Pauli's description of theories so badly understood and ill-defined that you can't even tell whether they are right or wrong. This applies both to string theory and to the non-string theory ideas I've been thinking about. I wanted to write about both in the weblog, have much greater hopes for the latter than the former.

Peter

[rick1138]

notevenwrong,

What is your opinion of Nambu's interpretation of the dual resonance model. Do you consider this to be example of a physical prediction made by string theory? If not why not?

[notevenwrong]

Originally posted by jeff
Hi Peter,



Would you mind offering some advice on how to approach your polemic on string theory to people who campaign against stringy research without even attempting to understand it's basic ideas (or even those of QFT, as is true for some people here at PF)? It might even help if you could say something about what you feel the purpose of polemical writing is in general. Thanks.

The thing I wrote a few years ago and my public criticisms of string theory have a definite purpose. I think the way string theory has come to so heavily dominate particle theory is unhealthy in the extreme. Some of my writing is "polemical" in the sense that it tries to counter the extensive unbalanced hype about string theory with a an exposition of the arguments against string theory, not necessarily balanced by trying to include every good thing I can think of about string theory. I hope that this will get people to understand that the arguments for string theory are nowhere near as strong as they are generally made out to be.

My writing is most directly aimed at those working in the field, hoping to get them to stop and think about what is going on, whether or not I might be right that the situation has gotten very unhealthy, and if so, what can be done about it.

As for others, I encourage people who are just learning this stuff to spend a lot of time learning QFT and some time learning string theory. Much of string theory is really 2d QFT, which is a fantastic subject.

More and more I've become convinced that a large part of the problem with string theory is that it has become a huge, very intricate and difficult business. Most physicists don't understand it very well so are reluctant to criticize it. Others end up getting sucked into the huge set of questions that such a complex thing leads to and never get out.

I'm not going to spend my time worrying about the large number of people who don't know what they are talking about who criticize string theory, there are plenty of these, but at least as many who sing its glories. What I'd like to do is to make sure people have access to both the arguments for and against string theory. They then need to make up their minds what to spend their time learning and working on.

[Urs]

Concerning Matrix Models, since they are non-perturbative, there is no need to pick any background. They pick their own solutions. That's what the papers that I was referring to tried to compute, namely the (maybe unique?) solution of the IKKT model. Of course it hasn't been done yet, obviously, but the fact that the IKKT model for one is conceptually exteremely simple and, for finite size N of the matrices, effectively calculable. You should endorse that, because if it turns out that the unique solution to IKKT is not phenomenologically realistic, then that's it.

On the other hand, I would find it hard not to be fascinated by a working theory of quantum gravity in any number of dimensions > 3. That's what I find so hard to understand about the criticism of string theory. If nothing else, there is lots of theoretical insight in string theory. If it really describes our world is a completely different issue. Lots of field theories are also studied only for theoretical reasons, having nothing directly to do with the real world. I don't want to wait for the unique prediction of my telephone number until I consider to find progress in quantum gravity interesting.

[Haelfix]

'You should endorse that, because if it turns out that the unique solution to IKKT is not phenomenologically realistic, then that's it. '

Urs can you expand on this a little, im rather curious by what you mean.

Assuming no realistic solution is found, would it outright falsify any 11 dimensional model without compactified dimensions based on Stringy mechanics?

Or is there enough subtleties to either argue it away, or criticize the validity of the actual model itself?

[notevenwrong]

Concerning Matrix Models, since they are non-perturbative, there is no need to pick any background. They pick their own solutions. That's what the papers that I was referring to tried to compute, namely the (maybe unique?) solution of the IKKT model. Of course it hasn't been done yet, obviously, but the fact that the IKKT model for one is conceptually exteremely simple and, for finite size N of the matrices, effectively calculable. You should endorse that, because if it turns out that the unique solution to IKKT is not phenomenologically realistic, then that's it.

On the other hand, I would find it hard not to be fascinated by a working theory of quantum gravity in any number of dimensions > 3. That's what I find so hard to understand about the criticism of string theory. If nothing else, there is lots of theoretical insight in string theory. If it really describes our world is a completely different issue. Lots of field theories are also studied only for theoretical reasons, having nothing directly to do with the real world. I don't want to wait for the unique prediction of my telephone number until I consider to find progress in quantum gravity interesting.

I'm no expert on the IKKT model, so don't know exactly what the problems with it are. If it really did give a well-defined, background-independent, non-perturbative formulation of M-theory, one that seemed to lead to dynamically determining a plausible background, my guess is that everyone in the field would be working on it. As far as I can tell, most people have lost interest in it. When that happens there's generally a good reason. Unfortunately I doubt that killing the IKKT model would kill the whole string/M-theory field.

I'm not claiming string theory is completely uninteresting. I am claiming it is overhyped and it has become difficult for young people to make careers working on anything else, which is very unhealthy. The reasons I don't believe in string/M-theory 11-d supersymmetric unification are two-fold:

1. It's really complicated and ugly

2. It not only doesn't predict your phone number, it doesn't predict anything at all.

[marcus]

The thing I wrote a few years ago ...tries to counter the extensive unbalanced hype about string theory ...

that's an extreme and incomplete condensation, I hope not unfair.

my point is that I dont think of that essay as primarily a polemic
it sounds to me more like the old and risky Quaker tradition of
speaking truth to power

which is rightly (I think) considered in that tradition to be an act of grace
and definitely more intriguing to watch than a simple polemic

Haelfix raised the issue of what is your "main beef" and got me curious.
He suggested it was lopsided funding. I want to try to get the essential
points isolated and in focus, at least for me. I dont hear a complaint (which is I guess what a beef is) and maybe I hear more a warning and a demand for integrity. Have to reflect a bit.

[marcus]

Peter Woit,

in your "An Evaluation" essay you make a mathematical comparison
between the Standard Model (where "two of the most important concepts... are that of a gauge field and that of the Dirac operator") and String theory
where those two concepts are "not fundamental, but are artifacts of the low energy limit".

You say:
"The Standard Model is dramatically more 'elegant' and 'beautiful' than string theory in that its crucial concepts are among the deepest and most powerful in modern mathematics."

this is something which as a non-expert with however some mathematical experience I would like to get in clearer focus. Maybe you have a alternative line of development in mind which does embody the strengths of 20th c mathematics in a more fundamental way.

It sounds as if particle physicists may have dragged things off into some place where they feel happy with the mathematics but which is not the direction theoretical physics is ultimately going to go and not, ultimately, in their own best interest. this is just a vague suspicion. sorry if too vague.

[notevenwrong]

Haelfix raised the issue of what is your "main beef" and got me curious.
He suggested it was lopsided funding. I want to try to get the essential
points isolated and in focus, at least for me. I dont hear a complaint (which is I guess what a beef is) and maybe I hear more a warning and a demand for integrity. Have to reflect a bit.

I think you've got it right. My point of view is that the over-hyping of string theory has lead to a really unhealthy situation in particle theory, and the remedy for this is for people to start honestly evaluating the results of the last 20 years work on the subject. I think if they do that they'll conclude that the idea of unifying the standard model and gravity in a 10/11 dimensional supersymmetric string/M-theory simply doesn't work. Once they get used to that idea, maybe people will start thinking about other more promising things.

[notevenwrong]

Maybe you have a alternative line of development in mind which does embody the strengths of 20th c mathematics in a more fundamental way.

It sounds as if particle physicists may have dragged things off into some place where they feel happy with the mathematics but which is not the direction theoretical physics is ultimately going to go and not, ultimately, in their own best interest. this is just a vague suspicion. sorry if too vague.

I tried to explain the alternative line of development I have in mind in
hep-th/0206135
That paper also refers to an old paper of mine in Nucl. Phys. B., which explains an idea about the relation of space-time geometry to the standard model.

This stuff is all very vague at this point, I certainly don't have a well-understood way of implementing many of the ideas that seem promising to me. This is all just as "Not Even Wrong" as string theory, maybe more so. But I think it's at least mathematically more attractive. If good mathematics leads to good physics, this may go somewhere.

[jeff]

As far as I can tell, most people have lost interest in it [the IKKT model]. When that happens there's generally a good reason.[/B]

This together with it's converse, that an idea's dominance speaks well of it's promise, makes your position more difficult to defend. Keep in mind that theory selection in an exact science like physics is very different than in the social sciences in which subjective opinion necessarily plays a much larger role.

[Urs]

As far as I can see research on Matrix Models is hampered by the fact that it is - difficult! :-)

When you hear the Potsdam group, Nicolai et al., speak about their reserach in supermembrane/BFSS model, you'll note that they will tell you that after fascinating results to lowest order (graviton scattering described by a simple matrix model, just imagine! :-) progress to higher orders is becoming really difficult, computationally.

The same seems to be true for the IKKT model. They have apparently run numerical computer programs for quite a while to see if they can approximately compute aspects of the exact solution, but they would need much more computation power to do that. I'll look up the links for you.

[Urs]

Here are some links to papers that discuss attempts to derive non-perturbative phenomonology (like 4-d spacetime) from stringy matrix models:

http://golem.ph.utexas.edu/string/archives/000314.html#c000863

[marcus]

I tried to explain the alternative line of development I have in mind in
hep-th/0206135
That paper also refers to an old paper of mine in Nucl. Phys. B., which explains an idea about the relation of space-time geometry to the standard model.


"Quantum Field Theory and Representation Theory: a Sketch"
http://arxiv.org/hep-th/0206135

I downloaded this paper to see whether it was entirely inaccessible to me or whether I could catch some of the drift of the conclusions...

Focusing momentarily on a part of the conclusions:
-------exerpt from "QFT and Representation Theory: a Sketch"----

While the difficulties one runs into in trying to quantize gravity in the standard way are well-known, there is certainly nothing like a no-go theorem indicating that it is impossible to find a quantum field theory that has a sensible short distance limit and whose effective action for the metric degrees of freedom is dominated by the Einstein action in the low energy limit. Since the advent of string theory, there has been relatively little work on this problem, partly because it is unclear what the use would be of a consistent quantum field theory of gravity that treats the gravitational degrees of freedom in a completely independent way from the standard model degrees of freedom.

One motivation for the ideas discussed here is that they may show how to think of the standard model gauge symmetries and the geometry of space-time within one geometrical framework.

Besides string theory, the other part of the standard orthodoxy of the last two decades has been the concept of a supersymmetric quantum field theory. Such theories have the huge virtue with respect to string theory of being relatively well-defined and capable of making some predictions. The problem is that their most characteristic predictions are in violent disagreement with experiment. Not a single experimentally observed particle shows any evidence of the existence of its 'superpartner'...

----end of quote----

edit: remove inessential comment

[selfAdjoint]

Breaking news! Peter Woit (http://www.math.columbia.edu/~woit/blog/) has important news for this glorious first of April.

[pelastration]

Breaking news! Peter Woit (http://www.math.columbia.edu/~woit/blog/) has important news for this glorious first of April.
... isn't this ... what I told you DickT? There was no concept.
But www.superstringtheory.com should be active again in some hours. ;-)

[pelastration]

But www.superstringtheory.com should be active again in some hours. ;-)
So, in my time it's now April 2.
Peter Woit made a great joke.
But seriously, the forum of www.superstringtheory.com should be active again today ... or on April 3? . That's what Patricia promised. Let's see if here server works.

[marcus]

Breaking news! Peter Woit (http://www.math.columbia.edu/~woit/blog/) has important news for this glorious first of April.

About time! :biggrin:


BTW I see Physics Forums got a mention in Woits blog

[jeff]

So, medical school or law school: Which type of janitorial position should I go for?

[selfAdjoint]

Look at it this way: At least you weren't outsourced! :biggrin:

[eforgy]

Peter must be getting a good chuckle out of this thread (if he's aware of its existence) :)

[lethe]

Peter must be getting a good chuckle out of this thread (if he's aware of its existence) :)
he is definitely aware of it. he posted to it.

[eforgy]

Oh well. That is less fun then :)

I read the first post by selfAdjoint (without noting the earlier March date) pointing to the weblog, but I did so just yesterday so the first entry I saw there was his April 1 entry. I assumed this whole thread represented a duping by him on us all :)

In any case, I thought it was fun. Thanks Peter! :)

More seriously, I totally agree with the charge that string theory is over hyped. In fact, I personally think theoretical physics as a whole has been headed in the wrong direction since the (in?)famous Einstein/Bohr debates. If I could go back in time and witness any event (series of events actually) in history, it would most definitely be the Einstein/Bohr debates. I would go even as far to say that one of the reasons theoretical physics has made as little progress as it has in the last 50+ years is due to not taking Einstein's later arguments more seriously.

Best regards,
Eric

[marcus]

I would go even as far to say that one of the reasons theoretical physics has made as little progress as it has in the last 50+ years is due to not taking Einstein's later arguments more seriously.

Best regards,
Eric

please expand
(might eventually need a separate thread since outside topic of Woit's blog)

[jeff]

I...agree...that string theory is over hyped.

This isn't a simple case of stupidly putting all our eggs in one basket. Strings is the only quantum gravity theory we know of, and we only found it by accident. It's an enormously deep theory rich in ideas that we don't yet understand, but that have produced new and powerful perspectives on what is already known, and serve as points of departure for the discovery of new physics that could end up leading us away from strings as well as any other idea. In other words, strings is not in any sense a stagnant research program. String theorists don't deny the basic merit in warnings against creating an environment unfriendly to nonstringy ideas, but they really do feel that given what we understand about strings and our previous failures to quantize gravity, the current concentration of effort on it, though troubling to some and worth discussing, is justified. It's also a lot of fun.

[eforgy]

In other words, strings is not in any sense a stagnant research program. String theorists don't deny the basic merit in warnings against creating an environment unfriendly to nonstringy ideas, but they really do feel that given what we understand about strings and our previous failures to quantize gravity, the current concentration of effort on it, though troubling to some and worth discussing, is justified. It's also a lot of fun.

I agree 100% and I think from what I've read that Peter would agree too. The point is, as Peter more eloquently stated, that things seem to have gotten to the point where research in nonstringy ideas is discouraged (at least indirectly by lack of funding opportunities). That is sad.

I'm attracted enough by what string theory has to offer that I am presently trying to learn some of the basics myself (as you can probably tell by skimming the String Coffee Table). However, I certainly don't think string theory (in its present form) is the right theory, although it may (just as LQG may) help foster ideas in the right direction. In this regard, it is definitely worth learning.

Eric

[marcus]

...In any case, I thought it was fun. Thanks Peter! :)

More seriously, I totally agree with the charge that string theory is over hyped. In fact, I personally think theoretical physics as a whole has been headed in the wrong direction since the (in?)famous Einstein/Bohr debates. If I could go back in time and witness any event (series of events actually) in history, it would most definitely be the Einstein/Bohr debates. I would go even as far to say that one of the reasons theoretical physics has made as little progress as it has in the last 50+ years is due to not taking Einstein's later arguments more seriously.

Best regards,
Eric

I wish you would explain the historical perspective more clearly. I had the impression that it is only in the last 20+ years that progress in theoretical physics fails to get regular verification and guidance from experiment.

I had the impression that from the Fifties until at least 1980 there was a kind of triumphant march of theory with experiment hand in hand (excuse the metaphor :) if possible) where theoreticians would predict something and then in a matter of months the people at the accelerator would find it.

Do you mean this could have been better if the theoreticians had taken to heart the later sayings of Einstein? It is an intriguing idea and may have an important germ of truth as afterthoughts sometimes do have. But I do not see how and wish for some clarification.

[sol2]

From a laymen's perspective, the second revolution has already happened. Just to point out where this has lead too. M Theory?:)

Imagine now then, developing perspective in regards to Warp Drive, from a brane scenario?

Most certainly there is a architectual apparatus that is mathematically driven, but like understanding gravitational waves, the graviton helps us to recognize the dimensional perspective of the bulk? Do we then dismiss this new perspective?

I am open to corrections

[marcus]

Before April 1 ( chuckling over the spoof in the blog) we were discussing
Woit's criticism of excess hype and unbalanced funding.
notevenwrong responded to this:

Haelfix raised the issue of what is your "main beef" and got me curious.
He suggested it was lopsided funding. I want to try to get the essential
points isolated and in focus, at least for me. I dont hear a complaint (which is I guess what a beef is) and maybe I hear more a warning and a demand for integrity. Have to reflect a bit.

I think you've got it right. My point of view is that the over-hyping of string theory has lead to a really unhealthy situation in particle theory, and the remedy for this is for people to start honestly evaluating the results of the last 20 years work on the subject. I think if they do that they'll conclude that the idea of unifying the standard model and gravity in a 10/11 dimensional supersymmetric string/M-theory simply doesn't work. Once they get used to that idea, maybe people will start thinking about other more promising things.

[selfAdjoint]

I've been rereading Kaku's Hyperspace (thought I ought to) and I was struck by the way he described the enthusiasm and hope of the physicists who developed 10 dimensional supergravity in the 1980s. They thought for a while they had IT, the theory of everything. But it turned out to be unrenormalizable. Just wrong.

Superstrings, and string physics generally, has never sent this signal. One of the first things proven in it was that it didn't require renormalization, because the worldsheets didn't intersect in points, as world lines of particles did. So the situation is not quite "not even wrong", because the failure of the "wrong" signal to appear is not due to the weakness of the theory but to its strength.

Because they never have had the theory itself tell them it was hopeless, string physicists have never given up hope. They have gone farther and farther, and how ever far it is, the math tells them it's OK to press on. I can't help but feel that some of the string physicists are wandering in the wilderness, but their stuff is still mathematically sound, so how can you tell? At least one of the posters on the new string board feels the huge landscape of vacua is amenable to calculation and not that big a threat. More power to him.

[marcus]

... At least one of the posters on the new string board feels the huge landscape of vacua is amenable to calculation and not that big a threat. More power to him.

sA it was a real delight that you tuned us into Woit's blog! I check it every 5 or 6 days or so. notevenwrong has commended the new board and commented just yesterday on what I imagine are the same posts you are referring to here. His comment is "pass the popcorn!"

http://www.math.columbia.edu/~woit/blog/

--------exerpt from "Not Even Wrong" blog-----
April 07, 2004
KKLT Smackdown
I was dubious of the value of a new "sci.physics.strings" newsgroup when it was first proposed, but now must admit it seems to have been a great idea It started up a week or two ago, and quickly someone asked the seemingly innocuous question of how many different possible vacuum states were expected in string theory. This is a hugely controversial issue among string theorists, largely because recent evidence is that the number is definitely astronomically large, and this makes it very unlikely that current ideas about string theory can ever be used to predict anything about the real world.

A lot of the discussion revolves around the "KKLT" proposal for constructing a large number of these vacuum states. The acronym is the initials of the authors, three of whom are at Stanford: Shamit Kachru, Renata Kallosh and Andrei Linde. Also at Stanford is Lenny Susskind, who has been spending the last year or so going around giving talks on the "Landscape of String Theory". It's hard to believe this, but Susskind's claim is essentially that the lack of predictivity of string theory is a good thing, since it allows so many possibilities that anything can happen. One can then invoke the "Anthropic Principle" to explain why the world is the way it is. It seems that Susskind is even writing a book about this wonderful "discovery".

Amazingly enough, the thread about this on sci.physics.strings, entitled "Conceptual question", has brought a public attack on the "Stanford propaganda machine" by a well-known European string theorist (Wolfgang Lerche), a detailed defense of his ideas by one of the KKLT authors (Kachru), contributions from the inimitable Lubos Motl from Harvard, and, while I was writing this, a defense of the anthropic principle from Joe Polchinski just appeared, which attacks the "cult of monovacuism" embodied by David Gross and Ed Witten.

Thanks are due to the creators of this newsgroup. Pass the popcorn!

-----------end quote-------------

sA you know I very much like the woity style of writing and
fully concur with his assessment that Lubos Motl is inimitable
and moreover I detect within myself distinct leanings towards monovacuism
woit IS the popcorn in this movie

[selfAdjoint]

Well, I find Woit kind of a guilty pleasure. It bugs me that the whole discussion is so snarky - I don't see how any of that will affect the outcome one way or another. And I am perfectly willing to get slammed by both sides because I won't play party politics with the future of physics.

Physics is a gift physicists give to humanity. The hard work of creating that gift is a high calling. To play the schoolyard squabbler in the middle of that is very sad to see.

[marcus]

... And I am perfectly willing to get slammed by both sides because I won't play party politics with the future of physics.

I agree. The way your interests and intuitions differ from mine (as well as coincide) are like a compass needle to me.
the diversity of honest views from intelligent people is just about the most valuable thing this kind of situation offers

We probably both deplore mafia-like activity or slamming or self-righteous bullying.

Simple squabbling I dont mind. Scholars (Newton/Leibniz) have traditionally conducted squabbles of epic proportion. We small fry may continue the custom without too much embarrassment. Maybe it is a form of mass entertainment. I expect to be permitted to express my leanings---interest in A and non-interest in B---and give reasons without being attacked. I dont object when other people express different interests and give reasons, although I may occasionally disagree.

I also do not object to satire. Sometimes admonishment doesnt work. Mafia-like activity, bullying, thought-policing, slamming people who dont toe the line or belong to the correct "camp" may persist despite moral objection. If someone resorts to satire (whether a big guy like Moliere or a little guy like Peter Woit) I am delighted. It's a literary pleasure that I'm not going to feel guilty for enjoying!

For some reason EB White's book about a mouse called Stuart Little comes to mind. when the mouse taught school there was only one rule (dont be mean) did you ever read that to your kid(s)?

[jeff]

What are your feelings on trying for sci.phys.lqg?

[marcus]

What are your feelings on trying for sci.phys.lqg?

that is a pleasant question to consider
thanks for asking it, hope some folks will reply
(I cant right now because have to go out on Easter errands)

[chroot]

jeff,

You mean, in trying to get such a group created?

- Warren

[jeff]

jeff,

You mean, in trying to get such a group created?

- Warren

Yes! Peter woit commented to the effect that he now likes the idea of sps since it's already reflecting the kind of decension among string theorists that characterize his own views. However, the decension on these issues has always been quite open. But I've never seen the same kind of open decension among members of the lqg camp. Maybe they all agree that getting lqg to work is just an unimportant technicality? Anyway, extablishing sci.phys.lqg probably isn't all that realistic.

[Haelfix]

If you think petty squabbling is the norm in String Theory, I invite everyone to attend cosmology and astrophysics seminars. Its usually best on the subject of galaxy structure and inflation.

Its Kinda amusing actually, grown men with Iqs off the chart, reducable to something not unlike kindergarden behaviour.

[jeff]

If you think petty squabbling is the norm in String Theory

Who said anything about "petty squabbling"?

[sol2]

I think everyone accepts the polarizations of these respective camps.

Without some kind of dualism ( not mean spirited), how would we see where such perfection might arise? I find Woit refreshing....even though I like strings.

Being a novice, it brings to mind the idea of the Solvay meetings and gedankin experiments that challenge the mind:) Logic does find its way into the arguement. Just takes a open ear, and mind, that if the spin goes one way it most certainly is simultaneous in another:)

Remember voice of a nOvice:)

[selfAdjoint]

Conflict is bound to arise, but mean-spiritedness is not necessary. Everyone now deplores the vicious priority fight between the followers of Newton and those of Leibniz. What do ad hominem attacks and thread ploys do to inspire the audience?

[arivero]

What do ad hominem attacks and thread ploys do to inspire the audience?

They hide any other contestants.

[marcus]

thread's topic is Peter Woit's blog,
so probably germane to note today's new entry
-----exerpt---
April 22, 2004
HEPAP
"HEPAP" is the Department of Energy's "High Energy Physics Advisory Panel", which holds meetings 3-4 times a year....

...HEPAP also adopted a new report on the "Quantum Universe". This follows the trend of recent years of trying to justify particle physics research by emphasizing its relation to the very healthy and sexy field of cosmology. The acid test of this over the next few years will be to see if it helps with the difficult problem of getting funding for the Linear Collider.

Posted by woit at 11:54 AM
-----end quote---

Personally I dont feel that Woit's blog engages in anything remotely
like what was being discussed just now above namely such things as

slamming for not toeing some party line
ad hominem attacks
meanspiritedness

And I dont think sA's remarks were intended to suggest
anything of that sort about the blog.
I think it's often a breath of the fresh
and if anything sometimes a bit too bland and sanitized
(maybe he's taken a bit of flak and is watching his step)

[notevenwrong]

"bland and sanitized"? Oh, no, I may have to quickly find some red meat for my loyal readers.
Maybe they'll like the latest post about Lubos Motl. If anyone feels it is mean-spirited I should point out that I only describe him as a "rabid fanatic" because I'm pretty sure he'd be proud of the designation.

The incoming flak seems to have mostly stopped, perhaps because it was met with devastating retaliation. Not watching my step any more or less than I ever have been. I'm just a sunny-dispositioned guy who always thinks the best of people.

[selfAdjoint]

You'll find my opinion on your Lubos post on my congratulation to him thread.

[sol2]

"bland and sanitized"? Oh, no, I may have to quickly find some red meat for my loyal readers.
Maybe they'll like the latest post about Lubos Motl. If anyone feels it is mean-spirited I should point out that I only describe him as a "rabid fanatic" because I'm pretty sure he'd be proud of the designation.

The incoming flak seems to have mostly stopped, perhaps because it was met with devastating retaliation. Not watching my step any more or less than I ever have been. I'm just a sunny-dispositioned guy who always thinks the best of people.

I believe as long as the spirit of Solvay is realized, and the counter arguments are sound, then there is nothing to be afraid of. It is a immediate recognition by all sides. From that logic, progress can be made.

To inject mean spiritedness, is something part parcel of the characters, not the math, so we can see where this can be moved past:)

From a child of the universe :biggrin:

[marcus]

... I'm just a sunny-dispositioned guy who always thinks the best of people.

...should never have said bland and sanitized. Glad the flak has abated. This loyal reader confesses that a bit of red meat now and then contributes to my own sunny disposition.

[marcus]

26 April
Woit blogged today
http://www.math.columbia.edu/~woit/blog/

27 April
and again today

the 27 April post concerns arcane algebraic geometry:
the "Langlands program" and
the recent proof of the Fundamental Lemma by Laumon ( 91 pages in French.)
for the foolhardy or intrepid, here's a sample of Laumon talking about these things in English
http://arxiv.org./alg-geom/9711021

[marcus]

Woit blogged 30 April and 8 May
(just a reminder, when there are fresh ones posted,
for folks who dont bother to check the site regularly)

the 8 May one is about Eric Baum's book "What Is Thought"
it has links to a review of Baum's book by Edward Witten
and to some online discussion of the book, as well as to some
condensed presentation of the main ideas

[selfAdjoint]

I went back to his site just now to refresh my memory on his Konstant Dirac Operator post. It's still over my head. But what excited me is that he has now added a post criticising Lubos Motl's screed against John Baez on sci.physics.strings. The way that forum has developed makes me wish I had never voted for it.

[marcus]

10 May blog was the one on Pottery referred to here by selfAdjoint
Today's 15 May blog is about a recent talk by Leonard Susskind
on the stringerous and braneful Landscape

http://www.math.columbia.edu/~woit/blog/

[added in edit] again today 17 May, Peter's report from the same
conference: this time on talks by Givental and by Witten

[marcus]

http://www.math.columbia.edu/~woit/blog/

Woit blogged again today: 19 May
commenting on a Slate interview with
the highly imaginative Andrei Linde

Woit appears not to relish Linde's pontification

I just checked the site again and Woit has posted a second, longer,
entry for 19 May----commenting on the decline of SUSY's popularity.
This is a followup on the report of Susskind attacking Supersymmetry
as a string hope. The operative word is "epicycle" the extra gadgetry
added to the Ptolemaic model to make the planets go how they should.

"I had thought this point of view was just Susskind being provocative, but today a new preprint appeared by Nima Arkani-Hamed and Savas Dimopoulos entitled "Supersymmetric Unification Without Low Energy Supersymmetry and Signatures for Fine-Tuning at the LHC". In this article the authors go over all the problems with the standard picture of supersymmetry and describe the last twenty-five years or so of attempt to address them as "epicyclic model-building". They claim that all these problems can be solved by adopting the anthropic principle (which they rename the "structure" or "galactic" or "atomic" principle to try and throw off those who think the "anthropic" principle is not science)..."
Can it be that post-modern Theoretical Physics is considering new names for the anthropic principle?

[marcus]

Woit blogged 23 May about the Spires database citations report for 2003 that just appeared

I notice that the 4th part, about gr-qc papers, is not even out yet for 2003,
but the hep-th parts are
and Michael Peskin has done his usual review for the year

as might be expected, it illustrates the shift in frequency of citation away from string/M papers and towards
cosmology, neutrino etc papers----a shift of interest in the research world
that is easily seen by comparing the list of topics in the 2003 review with the same list in the 2000 and 1999 reviews

Peskin's reviews reflect the ranking of the topics of the 40 (or howevermany) most-cited papers of that year. for instance in 2003 cosmology papers were apt to be most cited, whereas in 1999 that honor went to string papers.

the particle data group's report is always an automatic first, so the list of interest is what follows. Here is the order of the topic headings from Peskin's reviews for several years:

-------2003-----

http://www.slac.stanford.edu/library/topcites/2003/review.shtml

Particle Data Group - PDG
Cosmology
Neutrinos
Extra Space Dimensions
String Theory
High Energy Physics Resources

---------2000--------

http://www.slac.stanford.edu/library/topcites/topcites.review.2000.html

Particle Data Group - PDG
M-Theory
Non-Commutative Field Theory
Extra Space Dimensions
Cosmology
Neutrinos
High Energy Physics Resources

-----1999------

http://www.slac.stanford.edu/library/topcites/topcites.review.1999.html

Particle Data Group - PDG
Strings and Branes
Neutrinos
Extra Space Dimensions
CP Violation
High Energy Physics Resources

------------------
We actually dont need Peskin's reviews to abstract the trend because anyone can see the pattern for himself or herself by looking at the topcited 40 (or howevermany) listings for several years. Here are the "Top 40" lists for the same years

http://www.slac.stanford.edu/library/topcites/2003/annual.shtml
http://www.slac.stanford.edu/library/topcites/top40.2000.shtml
http://www.slac.stanford.edu/library/topcites/top40.1999.html

It used to be that the ten most-cited papers were mostly string
and now they are more likely to be mostly cosmology or astro of some sort. It is just a way of quantifying what everybody knows already: that cosmology/astroparticle is hot.

Anyway that is what I get out of the 2003 Spires report. Peter Woit called our attention to it and has additional comment in his blog.

[jeff]

...topic headings from Peskin's reviews...:

-------2003-----

http://www.slac.stanford.edu/library/topcites/2003/review.shtml

Particle Data Group - PDG
Cosmology
Neutrinos
Extra Space Dimensions
String Theory
High Energy Physics Resources

No surprise that high energy theory remains utterly dominated by strings, with LQG and every other approach languishing unmentioned on the margins.

[selfAdjoint]

See Woit's post today. The Spires database shows no new killer string papers. Woit concludes the particle physics (not just string) enterprise flatlined about 5 years ago. I think that it came out of the narrow valley into the wide plain and spread out into many small population threads. But nobody seems to be having the "next big idea". AJL is as good as any.

[marcus]

See Woit's post today. The Spires database shows no new killer string papers. Woit concludes the particle physics (not just string) enterprise flatlined about 5 years ago. I think that it came out of the narrow valley into the wide plain and spread out into many small population threads. But nobody seems to be having the "next big idea". AJL is as good as any.

Fascinating thought, that AJL could be an equal contender in the big horserace!
Spires does a separate "top 40" for the GR-QC sector and I havent seen
the 2003 results yet, many fewer researchers than in hep-th so much smaller scale, but I remember the 2002 report was interesting.

Notice that Ned Wright co-authored the #2 and #3 papers----he whose cosmology FAQ and tutorial we are always linking to here at PF!
A household figure for us, and his papers are the second and third most-cited by HEP researchers in 2003. Way to go Ned!

[marcus]

http://www.math.columbia.edu/~woit/blog/

the discussion there has gotten lively, with over thirtyfive comments to Woit's 19 May blog last time I looked

He blogged again ("Not Even Not Even Wrong") on 24 May---already six comments including a couple of entertaining ones from JC and Thomas Larsson about anthropisticism.

Posted by JC at May 25, 2004 07:51 PM:
--------------------------------------------
Did anyone ever try to cook up an "anthropic" explanation for something like the Balmer spectra of hydrogen, before the Bohr model ever existed?

It would be interesting to see what sort of phenomena had "anthropic" explanations more than century ago, which today have relatively well established theories and experiments.

It seems like "anthropic" explanations are not much more convincing that saying something happens because of "God's will" or that "it's the work of Satan" type of stupidity.
------end quote--------

Posted by Thomas Larsson at May 26, 2004 01:45 AM:
------------------------------------------------------------

Maybe you can argue that human life requires that the aether wind be neglible, which would explain the Michelson-Morley experiment.

------end quote-------

[elas]

Woit concludes the particle physics (not just string) enterprise flatlined about 5 years ago. I think that it came out of the narrow valley into the wide plain and spread out into many small population threads. But nobody seems to be having the "next big idea". AJL is as good as any.

I do not have the 'next big idea' but on one point Woit's critcism is wrong. Woit criticises string theory for predicting an infinite number of forces and particles and compares this with the fixed number predicted by the Standard Model.

Take the quark mass figures from the Particle Data Group, seperate them by charge and it will be seen that the mass figures for each charge increase according to a constant. A logarithmic graph of mass and charge shows that the production of particles occurs in steps with no limit to the number of steps. That means that the data used by the Standard Model, can be used to demonstrate the possiblility of an infinite number of fundamental particles and therefore Woit's arguement is not necessarily correct on that point. It could simply be that the Standard Model is not being correctly interpreted.

The table and graph have been added to the bottom of my webpage and are up for discussion in the Theory Developement Forum.

[marcus]

See Woit's post today. The Spires database shows no new killer string papers. Woit concludes the particle physics (not just string) enterprise flatlined about 5 years ago. I think that it came out of the narrow valley into the wide plain and spread out into many small population threads. But nobody seems to be having the "next big idea". AJL is as good as any.

To have some objective benchmark for comparison I went back to the Spires HEP database top Forty list of 1999 (the "about 5 years ago" Woit estimated) and filtered out everything that appeared in 1995 or earlier. So these are the papers most cited in 1999 which at that time had appeared recently---in the past 4 years. My impression is that it is heavily string. There were in 1999 many new killer string papers as you call them :smile:

As a comparison, one could do the same thing for the 2003 list. It would show, I think, comparatively few such----instead, a considerable shift or broadening of interest.

I posted the 2003 list further down the thread. In both cases the stringy papers are bolded to make them easy to pick out and judge what fraction of the list they represent.

----recent top cited papers in 1999---

REVIEW OF PARTICLE PHYSICS. PARTICLE DATA GROUP
By C. Caso et al
1269 citations

THE LARGE N LIMIT OF SUPERCONFORMAL FIELD THEORIES AND SUPERGRAVITY
By Juan Maldacena (Harvard U.).
Published in Adv.Theor.Math.Phys.2:231-252,1998
e-Print Archive: hep-th/9711200
625 citations

ANTI-DE SITTER SPACE AND HOLOGRAPHY
By Edward Witten (Princeton, Inst. Advanced Study).
Published in Adv.Theor.Math.Phys.2:253-291,1998
e-Print Archive: hep-th/9802150
464 citations

GAUGE THEORY CORRELATORS FROM NONCRITICAL STRING THEORY
By S.S. Gubser, I.R. Klebanov, A.M. Polyakov (Princeton U.).
Published in Phys.Lett.B428:105-114,1998
e-Print Archive: hep-th/9802109
425 citations

EVIDENCE FOR OSCILLATION OF ATMOSPHERIC NEUTRINOS
By Super-Kamiokande Collaboration (Y. Fukuda et al.).
Published in Phys.Rev.Lett.81:1562-1567,1998
e-Print Archive: hep-ex/9807003
382 citations

THE HIERARCHY PROBLEM AND NEW DIMENSIONS AT A MILLIMETER
By Nima Arkani-Hamed (SLAC), Savas Dimopoulos (Stanford U., Phys. Dept.), Gia Dvali (ICTP, Trieste).
Published in Phys.Lett.B429:263-272,1998
e-Print Archive: hep-ph/9803315
285 citations

NEW DIMENSIONS AT A MILLIMETER TO A FERMI AND SUPERSTRINGS AT A TEV
By Ignatios Antoniadis (Ecole Polytechnique), Nima Arkani-Hamed (SLAC), Savas Dimopoulos (Stanford U., Phys. Dept.), Gia Dvali (ICTP, Trieste).
Published in Phys.Lett.B436:257-263,1998
e-Print Archive: hep-ph/9804398
215 citations

PHENOMENOLOGY, ASTROPHYSICS AND COSMOLOGY OF THEORIES WITH SUBMILLIMETER DIMENSIONS AND TEV SCALE QUANTUM GRAVITY
By Nima Arkani-Hamed (SLAC), Savas Dimopoulos (Stanford U., Phys. Dept.), Gia Dvali (ICTP, Trieste).
Published in Phys.Rev.D59:086004,1999
e-Print Archive: hep-ph/9807344
202 citations

HETEROTIC AND TYPE I STRING DYNAMICS FROM ELEVEN-DIMENSIONS
By Petr Horava (Princeton U.), Edward Witten (Princeton, Inst. Advanced Study).
Published in Nucl.Phys.B460:506-524,1996
e-Print Archive: hep-th/9510209
179 citations

M THEORY AS A MATRIX MODEL: A CONJECTURE
By T. Banks (Rutgers U., Piscataway), W. Fischler (Texas U.), S.H. Shenker (Rutgers U., Piscataway), L. Susskind (Stanford U., Phys. Dept.).
Published in Phys.Rev.D55:5112-5128,1997
e-Print Archive: hep-th/9610043
170 citations

WHERE DO WE STAND WITH SOLAR NEUTRINO OSCILLATIONS?
By J.N. Bahcall (Princeton, Inst. Advanced Study), P.I. Krastev (Wisconsin U., Madison), A.Yu. Smirnov (ICTP, Trieste).
Published in Phys.Rev.D58:096016,1998
e-Print Archive: hep-ph/9807216
170 citations

LARGE N FIELD THEORIES, STRING THEORY AND GRAVITY
By Ofer Aharony (Rutgers U., Piscataway), Steven S. Gubser (Harvard U.), Juan Maldacena (Harvard U. & Princeton, Inst. Advanced Study), Hirosi Ooguri (UC, Berkeley & LBL, Berkeley), Yaron Oz (CERN).
e-Print Archive: hep-th/9905111
170 citations

STRONG COUPLING EXPANSION OF CALABI-YAU COMPACTIFICATION
By Edward Witten (Princeton, Inst. Advanced Study).
Published in Nucl.Phys.B471:135-158,1996
e-Print Archive: hep-th/9602070
167 citations

IMPROVED PARTON DISTRIBUTIONS FROM GLOBAL ANALYSIS OF RECENT DEEP INELASTIC SCATTERING AND INCLUSIVE JET DATA
By H.L. Lai, J. Huston (Michigan State U.), S. Kuhlmann (Argonne), F. Olness (Southern Methodist U.), J. Owens (Florida State U.), D. Soper (Oregon U.), W.K. Tung, H. Weerts (Michigan State U.).
Published in Phys.Rev.D55:1280-1296,1997
e-Print Archive: hep-ph/9606399
151 citations

EXTRA SPACE-TIME DIMENSIONS AND UNIFICATION
By Keith R. Dienes (CERN), Emilian Dudas (CERN & ORSAY, LPTHE), Tony Gherghetta (CERN).
Published in Phys.Lett.B436:55-65,1998
e-Print Archive: hep-ph/9803466
148 citations

TASI LECTURES ON D-BRANES
By Joseph Polchinski (Santa Barbara, ITP).
e-Print Archive: hep-th/9611050
146 citations

INITIAL RESULTS FROM THE CHOOZ LONG BASELINE REACTOR NEUTRINO OSCILLATION EXPERIMENT
By CHOOZ Collaboration (M. Apollonio et al.).
Published in Phys.Lett.B420:397-404,1998
e-Print Archive: hep-ex/9711002
146 citations

MEASUREMENT OF A SMALL ATMOSPHERIC MUON-NEUTRINO / ELECTRON-NEUTRINO RATIO
By Super-Kamiokande Collaboration (Y. Fukuda et al.).
Published in Phys.Lett.B433:9-18,1998
e-Print Archive: hep-ex/9803006
142 citations

ANTI-DE SITTER SPACE, THERMAL PHASE TRANSITION, AND CONFINEMENT IN GAUGE THEORIES
By Edward Witten (Princeton, Inst. Advanced Study).
Published in Adv.Theor.Math.Phys.2:505-532,1998
e-Print Archive: hep-th/9803131
139 citations

WEAK SCALE SUPERSTRINGS
By Joseph D. Lykken (Fermilab).
Published in Phys.Rev.D54:3693-3697,1996
e-Print Archive: hep-th/9603133
137 citations

STUDY OF THE ATMOSPHERIC NEUTRINO FLUX IN THE MULTI-GEV ENERGY RANGE
By Super-Kamiokande Collaboration (Y. Fukuda et al.).
Published in Phys.Lett.B436:33-41,1998
e-Print Archive: hep-ex/9805006
137 citations

PARTON DISTRIBUTIONS: A NEW GLOBAL ANALYSIS
By A.D. Martin (Durham U.), R.G. Roberts (Rutherford), W.J. Stirling (Durham U.), R.S. Thorne (Oxford U.).
Published in Eur.Phys.J.C4:463-496,1998
e-Print Archive: hep-ph/9803445
131 citations

BOUND STATES OF STRINGS AND P-BRANES
By Edward Witten (Princeton, Inst. Advanced Study).
Published in Nucl.Phys.B460:335-350,1996
e-Print Archive: hep-th/9510135
130 citations

ELEVEN-DIMENSIONAL SUPERGRAVITY ON A MANIFOLD WITH BOUNDARY
By Petr Horava (Princeton U.), Edward Witten (Princeton, Inst. Advanced Study).
Published in Nucl.Phys.B475:94-114,1996
e-Print Archive: hep-th/9603142
126 citations

----remaining items got less than 125 so weren't counted---

EVIDENCE FOR NU(MU) ---> NU(E) NEUTRINO OSCILLATIONS FROM LSND
By LSND Collaboration (C. Athanassopoulos et al.).
Published in Phys.Rev.Lett.81:1774-1777,1998
e-Print Archive: nucl-ex/9709006
124 citations

EVIDENCE FOR ANTI-MUON-NEUTRINO ---> ANTI-ELECTRON-NEUTRINO OSCILLATIONS FROM THE LSND EXPERIMENT AT LAMPF
By LSND Collaboration (C. Athanassopoulos et al.).
Published in Phys.Rev.Lett.77:3082-3085,1996
e-Print Archive: nucl-ex/9605003
122 citations

A LARGE MASS HIERARCHY FROM A SMALL EXTRA DIMENSION
By Lisa Randall (Princeton U. & MIT, LNS), Raman Sundrum (Boston U.).
Published in Phys.Rev.Lett.83:3370-3373,1999
e-Print Archive: hep-ph/9905221
120 citations

-----end of exerpt----
[edit: I have made an accurate count and added a summary]
to summarize in the 1999 HEP citebase there were 24 papers
which received 125+ citations.
Of these, 15 were recent string papers. (over 60 percent, a substantial percentage)

The number of citations these 15 recent string papers received that year were:
625, 464, 425, 285, 215, 202, 170 170, 167, 148, 146, 139, 137, 130, 126

[selfAdjoint]

Yes, heavily string, and only a few topics within string, dominated by the work of Witten and Maldacena. What would be interesting would be a comparison of the number of papers produced in 1993-1998 to the number of heavily cited ones, as a percentage. And then the same thing for 1998-2003. Then compare that to the actual numbers of papers produced (in stringy subjects). My guess would be meany more papers in the later quintennium but a lower rate of citation. Is this because there are no more gurus or because gurus are no longer needed?

[jeff]

You guys can play all of these silly games you want, but strings continue to dominate high energy theory and still serve as the richest source of new ideas in addressing the deepest problems of theoretical physics, including those in gauge theory, particle theory and cosmology.

[marcus]

Yes, heavily string, and only a few topics within string, dominated by the work of Witten and Maldacena. What would be interesting would be a comparison of the number of papers produced in 1993-1998 to the number of heavily cited ones, as a percentage. And then the same thing for 1998-2003...

I cant easily carry out the comparison you suggest. And BTW I do find it interesting and enlightening (as I suspect you do as well) to see what today's researchers most often cite for reference.

Here's the spires link in case anyone else wants to take a look:
http://www.slac.stanford.edu/library/topcites/

I got started with a FOUR year, instead of a five year, window. 1996 through end 1999.
to make a similar comparison for 2003 we need the topcited list for 2003, with papers appearing during the four years 2000 through end 2003.

when I go to the same Spires listing (now the top 100 instead of the top 40)
and do the same thing I get this. I have bolded those I recognize as by string people so the eye can pick them out:

-----recent topcited papers in 2003, for comparison----

1702
REVIEW OF PARTICLE PHYSICS. PARTICLE DATA GROUP
By Particle Data Group (K. Hagiwara et al.).
Most recent version published in Phys.Rev.D66:010001,2002

0812
FIRST YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: DETERMINATION OF COSMOLOGICAL PARAMETERS
By D.N. Spergel, L. Verde, Hiranya V. Peiris, E. Komatsu, M.R. Nolta, C.L. Bennett, M. Halpern, G. Hinshaw, N. Jarosik, A. Kogut, M. Limon, S.S. Meyer, L. Page, G.S. Tucker, J.L. Weiland, E. Wollack, E.L. Wright.
Published in Astrophys.J.Suppl.148:175,2003 [arXiv: astro-ph/0302209]

0505
FIRST YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: PRELIMINARY MAPS AND BASIC RESULTS
By C.L. Bennett, M. Halpern, G. Hinshaw, N. Jarosik, A. Kogut, M. Limon, S.S. Meyer, L. Page, D.N. Spergel, G.S. Tucker, E. Wollack, E.L. Wright, C. Barnes, M.R. Greason, R.S. Hill, E. Komatsu, M.R. Nolta, N. Odegard, Hiranya V. Peiris, L. Verde, J.L. Weiland.
Published in Astrophys.J.Suppl.148:1,2003 [arXiv: astro-ph/0302207]

0351
FIRST RESULTS FROM KAMLAND: EVIDENCE FOR REACTOR ANTI-NEUTRINO DISAPPEARANCE
By KamLAND Collaboration (K. Eguchi et al.).
Published in Phys.Rev.Lett.90:021802,2003 [arXiv: hep-ex/0212021]

0285
DIRECT EVIDENCE FOR NEUTRINO FLAVOR TRANSFORMATION FROM NEUTRAL CURRENT INTERACTIONS IN THE SUDBURY NEUTRINO OBSERVATORY
By SNO Collaboration (Q.R. Ahmad et al.).
Published in Phys.Rev.Lett.89:011301,2002 [arXiv: nucl-ex/0204008]

0197
STRINGS IN FLAT SPACE AND PP WAVES FROM N=4 SUPERYANG-MILLS
By David Berenstein, Juan M. Maldacena, Horatiu Nastase (Princeton, Inst. Advanced Study).
Published in JHEP 0204:013,2002 [arXiv: hep-th/0202021]

0189
MEASUREMENT OF DAY AND NIGHT NEUTRINO ENERGY SPECTRA AT SNO AND CONSTRAINTS ON NEUTRINO MIXING PARAMETERS
By SNO Collaboration (Q.R. Ahmad et al.).
Published in Phys.Rev.Lett.89:011302,2002 [arXiv: nucl-ex/0204009]

0189
WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) FIRST YEAR OBSERVATIONS: TEMPERATURE - POLARIZATION POLARIZATION
By A. Kogut, D.N. Spergel, C. Barnes, C.L. Bennett, M. Halpern, G. Hinshaw, N. Jarosik, M. Limon, S.S. Meyer, L. Page, G. Tucker, E. Wollack, E.L. Wright.
Published in Astrophys.J.Suppl.148:161,2003 [arXiv: astro-ph/0302213]

0186
FINAL RESULTS FROM THE HUBBLE SPACE TELESCOPE KEY PROJECT TO MEASURE THE HUBBLE CONSTANT
By W.L. Freedman, B.F. Madore, B.K. Gibson, L. Ferrarese, D.D. Kelson, S. Sakai, J.R. Mould, R.C. Kennicutt, H.C. Ford, J.A. Graham, J.P. Huchra, S.M.G. Hughes, G.D. Illingworth, L.M. Macri, P.B. Stetson, P.B. Stetson (Carnegie Inst. Observatories & Caltech, IPAC & Swinburne U., Ctr. Astrophys. Supercomput. & Rutgers U., Piscataway & Carnegie Inst., Wash., D.C. & NOAO, Tucson & Res. Sch. Astron. Astrophys., Weston Creek & Arizona U., Astron. Dept. - Steward Observ. & Johns Hopkins U. & Harvard-Smithsonian Ctr. Astrophys. & Cambridge U., Inst. of Astronomy & Lick Observatory & Dominion Astrophys. Obs., Victoria).
Published in Astrophys.J.553:47-72,2001 [arXiv: astro-ph/0012376]

0180
MEASUREMENT OF THE RATE OF NU/E + D --> P + P + E- INTERACTIONS PRODUCED BY B-8 SOLAR NEUTRINOS AT THE SUDBURY NEUTRINO OBSERVATORY
By SNO Collaboration (Q.R. Ahmad et al.).
Published in Phys.Rev.Lett.87:071301,2001 [arXiv: nucl-ex/0106015]

0177
THE SLOAN DIGITAL SKY SURVEY: TECHNICAL SUMMARY
By SDSS Collaboration (Donald G. York et al.).
Published in Astron.J.120:1579-1587,2000 [arXiv: astro-ph/0006396]

0162
FIRST YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: IMPLICATIONS FOR INFLATION
By H.V. Peiris, E. Komatsu, L. Verde, D.N. Spergel, C.L. Bennett, M. Halpern, G. Hinshaw, N. Jarosik, A. Kogut, M. Limon, S.S. Meyer, L. Page, G.S. Tucker, E. Wollack, E.L. Wright (Princeton U. & NASA, Goddard & British Columbia U. & Chicago U., EFI & CFCP, Chicago & Brown U. & UCLA).
Published in Astrophys.J.Suppl.148:213,2003 [arXiv: astro-ph/0302225]

0139
THE SLOAN DIGITAL SKY SURVEY: EARLY DATA RELEASE
By SDSS Collaboration (Chris Stoughton et al.).
Published in Astron.J.123:485-548,2002

0135
ROLLING TACHYON
By Ashoke Sen (Harish-Chandra Res. Inst. & Penn State U.).
Published in JHEP 0204:048,2002 [arXiv: hep-th/0203211]

0134
A PERTURBATIVE WINDOW INTO NONPERTURBATIVE PHYSICS
By Robbert Dijkgraaf (Amsterdam U. & Amsterdam U., Inst. Math.), Cumrun Vafa (Harvard U., Phys. Dept.). [arXiv: hep-th/0208048]

0133
A MEASUREMENT BY BOOMERANG OF MULTIPLE PEAKS IN THE ANGULAR POWER SPECTRUM OF THE COSMIC MICROWAVE BACKGROUND
By Boomerang Collaboration (C.B. Netterfield et al.).
Published in Astrophys.J.571:604-614,2002 [arXiv: astro-ph/0104460]

0130
THE COSMOLOGICAL CONSTANT AND DARK ENERGY
By P.J.E. Peebles (Princeton U.), Bharat Ratra (Kansas State U.).
Published in Rev.Mod.Phys.75:559-606,2003 [arXiv: astro-ph/0207347]

0126
SOLAR B-8 AND HEP NEUTRINO MEASUREMENTS FROM 1258 DAYS OF SUPER-KAMIOKANDE DATA
By Super-Kamiokande Collaboration (S. Fukuda et al.).
Published in Phys.Rev.Lett.86:5651-5655,2001 [arXiv: hep-ex/0103032]

0125
TYPE IIB GREEN-SCHWARZ SUPERSTRING IN PLANE WAVE RAMOND-RAMOND BACKGROUND
By R.R. Metsaev (Lebedev Inst.).
Published in Nucl.Phys.B625:70-96,2002 [arXiv: hep-th/0112044]

0125
INDICATIONS OF NEUTRINO OSCILLATION IN A 250 KM LONG BASELINE EXPERIMENT
By K2K Collaboration (M.H. Ahn et al.).
Published in Phys.Rev.Lett.90:041801,2003 [arXiv: hep-ex/0212007]
[Total number of citations in HEP]

.....
.....
(there are more, but this gives an impression how it goes)

Maybe someone else wants to look at some other years and do a similar count:
http://www.slac.stanford.edu/library/topcites/

[edit: I did a summary]
The Spires HEP topcited list had, when only recent articles are included, 20 papers which garnered 125+ citations.
Of these, 4 were stringy type research (a smaller percentage than in 1999, 25 percent instead of 60 percent)

the numbers of citations for these 4 string papers were:
197, 135, 134, 125

[marcus]

Another blog: 27 May
PW found some nice things to say about Lubos Motl!
"Motl is also a fierce opponent of the 'anthropic' arguments that have become popular among string theorists..."

[marcus]

About the Spires citations report, it surprised me that there were only 4 stringy papers (in the 4-year "recent" window) that got 125 or more citations----in the HEP publications appearing in 2003.

by contrast, if you look at the 1999 list a few posts back, there appear to be 15 or so recent stringy papers that got 125 or more citations

selfAdjoint has suggested several reasons for this drop-off, and it would
take more a thoughtful approach to the Spires data to see which explanations apply. in any case i guess one can say that nowadays there are fewer heavily-cited string papers than there used to be back in 1999,
and for whatever reasons research interests and research fashions change.
a drop from 15 to 4 is kind of stunning, i thought

[jeff]

About the Spires citations report, it surprised me that there were only 3 stringy papers (in the 4-year "recent" window) that got 125 or more citations----in the HEP publications appearing in 2003.

by contrast, if you look at the 1999 list a few posts back, there appear to be 17 or so stringy papers that got 125 or more citations

selfAdjoint has suggested several reasons for this drop-off, and it would
take more a thoughtful approach to the Spires data to see which explanations apply. in any case i guess one can say that nowadays there are fewer heavily-cited string papers than there used to be back in 1999,
and for whatever reasons research interests and research fashions change.
a drop from 17 to 3 is kind of stunning, i thought

These remarks are completely wrong and misleading: The numbers of highly cited papers can't reliably gauge the amount of activity in a research program since this number could be very low even though the total number of papers published - this being a far more accurate measure of levels of activity - is very high.

[notevenwrong]

These remarks are completely wrong and misleading: The numbers of highly cited papers can't reliably gauge the amount of activity in a research program since this number could be very low even though the total number of papers published - this being a far more accurate measure of levels of activity - is very high.

The claim is not that there isn't a lot of research activity in string theory, there's probably as many string theory papers being published as ever. What this data indicates is that there are no virtually no significant new ideas in string theory, or at least dramatically fewer in the period 2000-2003 than in any other four-year period during the twenty-year history of modern string theory. Until 2000, at any given moment much of what most string theorists were doing was working out the implications of new ideas that had come up in the past year or so. Since 2000, there just hasn't been much in the way of new ideas to chew on. I don't think anybody who seriously follows the string theory literature can deny this, and the numbers are clear.

[jeff]

The claim is not that there isn't a lot of research activity in string theory, there's probably as many string theory papers being published as ever. What this data indicates is that there are no virtually no significant new ideas in string theory, or at least dramatically fewer in the period 2000-2003 than in any other four-year period during the twenty-year history of modern string theory. Until 2000, at any given moment much of what most string theorists were doing was working out the implications of new ideas that had come up in the past year or so. Since 2000, there just hasn't been much in the way of new ideas to chew on. I don't think anybody who seriously follows the string theory literature can deny this, and the numbers are clear.

I said as much in the "Research demographics again" thread:

...The reduction in such highly cited papers merely reflects the fact that D-branes may have taken us about as far as they can on their own and that we need new tools to auger the next revolution in string theory...However, even in the absence of such a breakthrough, stringy papers continue to dominate high energy theory and drive to a considerable and growing extent theoretical cosmology.

[marcus]

the 31 May blog comments on a Michael Douglas paper that
just appeared:


"Statistical analysis of the supersymmetry breaking scale"
Michael R. Douglas (Rutgers/IHES/Caltech)
8 pages
http://arxiv.org/hep-th/0405279

Abstract:
"We discuss the question of what type and scale of supersymmetry breaking might be statistically favored among vacua of string/M theory, building on comments in Denef and Douglas, hep-th/0404116."

http://www.math.columbia.edu/~woit/blog/

[marcus]

Peter Woit's 3 June blog comments on the latest Witten paper
(in Nature vol 429, n. 6991, about electroweak symmetry breaking)
Woit supplies a link to Witten's paper and quotes Witten's opinion
concerning the "Anthropic Principle".

unfortunately the link only works for Nature subscribers
so this may mean a trip to the library

(not the paper in question but a related talk by witten at fermilab
in 2003:
http://conferences.fnal.gov/lp2003/program/papers/witten.pdf)



I am curious to know if the recent Nature article shows evidence of a shift in
the focus of Witten's attention. Since Spires database shows
much of the action in HEP
(recent top-cited papers etc) is outside string theory, I would
expect he might be developing other research interests and this paper
might be a straw in the wind. Has anyone looked at it?

[jeff]

Peter Woit's 3 June blog comments on the latest Witten paper
(in Nature vol 429, n. 6991, about electroweak symmetry breaking)
Woit supplies a link to Witten's paper and quotes Witten's opinion
concerning the "Anthropic Principle".

unfortunately the link only works for Nature subscribers
so this may mean a trip to the library

I am curious to know if this article shows evidence of a shift in
the focus of Witten's attention.

The way to answer this is to just email witten and ask him.

[marcus]

Peter Woit's 4 June blog:
he was visiting the physics department at Dartmouth this week
and gave a colloquium lecture on
"Quantum Field Theory and Representation Theory"

the blog gives a link to the outline and slides

BTW: the QFT/GroupReps lecture has some history too
and includes a funny conversation between Dirac
and an American newspaperman.

[selfAdjoint]

That interview between Dirac and a reporter from the Madison, WI Capital Times (I think it was) was terrific, I wish I had a link to the whole thing. At another point the reporter asks if anything worries Dirac about theory, and Dirac says Goedel.

[pelastration]

That interview between Dirac and a reporter from the Madison, WI Capital Times (I think it was) was terrific, I wish I had a link to the whole thing. At another point the reporter asks if anything worries Dirac about theory, and Dirac says Goedel.
Maybe this (a part?)? http://faculty.rmwc.edu/tmichalik/dirac.htm

[arivero]

It is not vain that Dirac is buried at the foot of Newton (er, and Newton on the right side of God's altar).

[selfAdjoint]

Maybe this (a part?)? http://faculty.rmwc.edu/tmichalik/dirac.htm

Oh I see it was the other Madison paper, The State Journal. Well it was a 50% shot. I notice that "Roundy" got more out of the notoriously taciturn Dirac than most physicists ever did. Also notice Roundy's use of Poincare in his guess of what Dirac's initials P.A.M. might be. R was not quite the ignorant hick he pretended to be!

[marcus]

I see Urs Schreiber responded today to one of Peter Woit's blogs

also someone called Roland Schwarz who could have the effrontery to be
related to the dreadful Bogdanov brothers.

Now the "comments" thread attached to Woits 5 June blog
has been taken over by Loons
or by one Loon pretending to be several
and it is already over a dozen posts long in a kind of
Loony Satire of scientific discussion.

they are actually a bit funny, or i suspect Peter Woit would
have squelched them

[marcus]

Now the "comments" thread attached to Woits 5 June blog
has been taken over by Loons
or by one Loon pretending to be several
and it is already over a dozen posts long in a kind of
Loony Satire of scientific discussion.


there are some remarkable dramatic characters who have appeared
in the comments of Woit's blog
named petitot
moyentot
and grantot

some appear to be French anti-scientific or "post-modern" parodists.
one may be another name for someone called "crankbuster"
I would like to know what some others think of these strange, sometimes quite funny, creatures.

in french letters there has been a cultivation of the art of sacrilege
going back for many centuries and I suppose it is only to be expected

there was that celebrated contemporary of Einstein called
Alfred Jarry of Pataphysics fame
these people do not seem all that different from jarry
but perhaps more well-versed and diabolically clever

http://www.math.columbia.edu/~woit/blog/

PS: BTW Woit blogged today, 10 June. It was about alleged proofs of the Riemann Hypothesis

[pelastration]

there are some remarkable dramatic characters who have appeared
in the comments of Woit's blog
named petitot
moyentot
and grantot

some appear to be French anti-scientific or "post-modern" parodists.
Probably it has to do with his June 5 comment "(quote)A couple years ago two French brothers, Igor and Grichka Bogdanov, managed to get Ph.Ds in France and publish several nonsensical papers about quantum gravity in refereed physics journals, several of them rather well-known and prestigious ones. John Baez has a useful web-page about this story.(end of quote).
Internet revenge.

[marcus]

Woit blogged again today 12 June
this time about "cosmic strings"

I've taken a look at Sean Carroll's "preposterous universe" blog
which seems highly entertaining especially about GW Bush
has some good cartoons, as well as science news
It looks like one can easily get into the habit of checking
into these mini-amusement-parks and private fun-houses
that people set up, another addictive feature of the internet

[selfAdjoint]

Check out his latest post (http://www.math.columbia.edu/~woit/blog/archives/000038.html) , about the reanalysis by the Tevatron group of the top quark mass, and the implications this has for the mass of the Higgs particle. Also many of us will want to follow his links, which between them constitute a nice little tutorial on the subject.

[marcus]

still more recently a 17 June post about
some expository mathematics by Barry Mazur
and a weekly "Basic Notions" seminar at Harvard which
is partly available online.

Woit also had some words today about a talk by Leonard Susskind
concerning, among other things, "the stupendous Landscape of string theory vacuua"
and a new string theory "rising from the ashes" of the already established string theory

[selfAdjoint]

Woit seems to be skeptical about Susskind's papers. Odd.

[arivero]

Check out his latest post (http://www.math.columbia.edu/~woit/blog/archives/000038.html) , about the reanalysis by the Tevatron group of the top quark mass, and the implications this has for the mass of the Higgs particle. Also many of us will want to follow his links, which between them constitute a nice little tutorial on the subject.

The top quark issue is also blogged in
http://golem.ph.utexas.edu/~distler/blog/archives/000380.html#comments
http://blogs.salon.com/0001092/2004/06/09.html#a690
http://preposterousuniverse.blogspot.com/

[John]

It's hard to follow all of the new technical terms, like blog, for non-string theory. But there seems to be an attack on string theory, and on funding for powerful accelerators, and on the acquisition of knowledge of the universe in general.

Not being a physics student, I am very good at physics. I started thinking about another model for the universe in about 1985. The strange thing was that all of my ideas seemed to connect with current physics. My ideas got more and more developed; so when the Internet came along, I started to post my ideas, hoping someone would have been lead in the same direction and I could start a discussion: that is, if my ideas were in the direction of right. I hoped my ides would receive some positive response, and we could develop the ideas further, not my ideas, but the right ideas. I kept meeting with a lot of agreement between my ideas and current physics.

Instead, my ideas met with negative attacks.

Here is one of my ideas. I believe protons are hollow spheres made of strings, just the way you would make a hollow sphere out of chicken wire. The “chicken wire” vibrates, and the mass of the vibrating "wire" inflates the proton. When we look at a proton, we only see the one string that is vibrating. We don’t see all the wires that make up the proton. It’s like studying a radio and only seeing the electrical impulses traveling along the wires, without seeing the wires. We would say is a radio is made of tiny electrical impulses, separated by vast distances of nothing. That is absurd, but we would swear that is exactly what the math is telling us, and it would be true.

I am seeing or imagining the wires that make up the proton, and not just the energy that is in the wires.

My latest discovery happened when I learned what a quark is, something every physicist knows, but I didn’t: there are three quarks in a proton. If a proton is a hollow sphere as I say, then each quark is one third of the sphere, so I can know the exact shape of a quark: it's shape is one-third the surface of a sphere. I cut a round orange in three parts and peeled the skin, which gave me one-third the surface of a sphere, so I have my theorized shape of a quark sitting on a table, sticky with orange juice.

What is a string? I say, it is the distance between two separate points. So I take ten quarters that represent points, and arrange them on a table. Start with three quarters to make a triangle, then add a fourth to make a diamond. Then add three more to make a solid hexagon. Add three more, and then you can precisely cover the quarters with the one-third orange peel. The ten quarters and the shape of the orange peel are the same.

Attach three of these quarks made of points together, and you have a hollow sphere. Electrons travel by vibrating one point, then another, then another. They soon vibrate the whole array of points, and you can’t really define where the electron is, except to say it is in the shape that “surrounds” the proton. But that shape is really the proton. The proton is not in the middle, but it IS the shape we call the electron cloud.

The fact ten seperate points make the exact shape of one-third the surface of a sphere is an amazing indication my ideas may actually be correct. I say the entire universe is made of individual points of matter, the way a dust cloud is made of individual specks of dust. Light and electrons travel from point to point, which means at the most basic level light can only travel in six directions, and it means there are two forms of dimension. There are spatial dimensions which contain 9 dimensions (plus time) for ten. And there are M-dimensions, which are the energized membranes that make up all the solid objects. It is easy to imagine a picture of that. The dots that make up the picture are arranged sparsely to form space, and they are arranged more densely to form objects.

[jeff]

and a new string theory "rising from the ashes" of the already established string theory

The actual quotation due to susskind is:

During the last couple of years an entirely new paradigm has emerged from the ashes of a more traditional view of string theory

I find the difference between this and your quote telling.

[marcus]

Peter Woit posted yesterday 1 July
pointing out that Susskind has now withdrawn
his paper about the "stupendous landscape"
and about the new Stringery which he sees "emerging from the ashes"
of yesterday's Stringery

this paper of Susskind, which happly I saved on my desktop
because it was so splendid
provided a window on
the current state of stringy affairs

[marcus]

Woit's 1 July blog also talks about the fact
that Mike Douglas paper of 30 May has gone through
several revisions already and is in its 4th version.

We should really try to follow some of this----it seems there is
a lot of vacillation about whether to "predict" (guess?)
the new collider will find evidence of supersymmetry or not,
at the energy level it will be able to acheive

At one time, string theory was supposed to "predict" supersymmetry would be found at that level (and earlier at even lower levels but it wasnt)
but the "predictions" now seem to have evaporated

Is it possible to make the theory predict whatever outcome one guesses is most likely? that would then be a limp and pliable theory. And we would see, as the deadline for prediction approaches, that people's guesswork waffles, and the "predictions" become drained of confidence and start to wobble.

Mike Douglas paper indicates not to expect LHC to see SUSY
and IIRC a recent talk by Witten in Davis carried the same message
and yet only a little while ago there was triumphant confidence---"just wait till LHC comes on line! that will show you skeptics!" It is strange and not a little funny.

[Ontoplankton]

Naive question from someone with no technical knowledge of string theory and therefore no opinion on its validity:

Here and elsewhere, I see a lot of people ridiculing the anthropic principle. Can anyone point me to an explanation of the objections to it on the level of rigor of e.g. Nick Bostrom's book (http://anthropic-principle.com/book)?

It just seems like basic common sense to me: if a theory says there are a lot of different worlds, and only some of them contain observers, then we should expect to be in one of those worlds that do contain observers. If we're in a sort of world that is atypical for the set of worlds claimed to exist, but typical for the set of worlds claimed to exist that also happen to contain observers, then this is not evidence against the theory.

I don't understand the people saying "the anthropic principle isn't falsifiable", either. If it's just a decision-theoretical (or confirmation-theoretical, whatever) principle, then why should it be falsifiable?

[Ontoplankton]

Mike Douglas paper indicates not to expect LHC to see SUSY
and IIRC a recent talk by Witten in Davis carried the same message
and yet only a little while ago there was triumphant confidence---"just wait till LHC comes on line! that will show you skeptics!" It is strange and not a little funny.

Are you saying this disconfirms string theory in some way? I don't see how. If different people claim the theory predicts different things, then that just means we don't know what the theory predicts yet, and we can maybe find out by thinking harder; it does not mean the theory can say anything we want.

Again, I don't know enough to have any opinion about string theory itself. But if anyone wants a meaningless data point: some of what I do understand of the objections by string theory's detractors looks unfair to me.

[selfAdjoint]

Are you saying this disconfirms string theory in some way? I don't see how.

Well if SUSY were to fall, so would superstrings and everything derived from them. You would still have bosonic strings and string field theory.

But it would seem to me that LHC could only falsify low energy SUSY extensions of the standard model. Corrections, anybody?

[marcus]

Hi Ontopl. (I guess it means "wandering being" in greek)

I was not sure about your reference to Anthropic principle so i looked back and the nearest post that mentioned it was my post #62.
as you see I was NOT criticizing Anthropic Principle!
quarreling about that principle is a symptom of troubles in string
(I watch but am not part of the quarrel)

the people to look at to see why they reject the Anthropic principle are the string theory insiders like Lubos Motl, David Gross, Edward Witten.

Rejecting the A.P. is part of their resistance to where Susskind has been going and leading a portion of the stringfolk with him.

The A.P. is not an issue for me since i dont find string/M theorizing interesting or relevant to the goal of a background indep. quantum theory of gravity.

I am more interested in theories that preserve the essential features of Gen Rel like background independence, and quantize it in as transparent and straightforward a way as possible.

but when people important in String say something about A.P. I try to keep track.

So my post #62 a ways back in this thread was keeping track of what Witten said about it.


Peter Woit's 3 June blog comments on the latest Witten paper
(in Nature vol 429, n. 6991, about electroweak symmetry breaking)
Woit supplies a link to Witten's paper and quotes Witten's opinion
concerning the "Anthropic Principle".

unfortunately the link only works for Nature subscribers
so this may mean a trip to the library

(not the paper in question but a related talk by witten at fermilab
in 2003:
http://conferences.fnal.gov/lp2003/program/papers/witten.pdf)

...

to get the latest Witten word on A.P. I guess you have to go back to that 3 June post of Peter Woit!

String seems to be in a muddle with some saying "Dont give up! We aren't forced to Anthropologize! Keep working to solve the basic problems!"

but on the other hand some like Susskind saying that the huge number of possible basic states (string vacua)----the "stupendous landscape" he has called it, of an estimated 10-to-the-100 power of distinct possible models of nature all with a potential for predicting distinct things about nature----can only be resolved by appealing to the A.P.

As you can imagine, I rather avoid arguing about the A.P.
My personal suspicion is that it is wishful thinking for String theorists to imagine that it could help them out of the
String theory crisis. Susskind looks to me like he is clutching at straws.

In the end a successful physical theory that pretends to improve on the Standard Model plus incorporate gravity has to explain certain numbers (numbers that the Standard Model explains, the cosmological constant, etc.)

Historical example: when Feynmann and Schwinger made QED the theory explained certain numbers, like the magnetic moment of the electron. (it did not thow up its hands in a vague appeal to the fact that we have a life-friendly universe)
this is what physical theories are supposed to do: explain why the magnetic moment of the electron is such-and-such.
That was the 1950s.
So? It is different now?

so I am sympathetic to what I think is an honorable courageous stand by string theorists who want their theory to have explanatory power.
they aren't ready to lower their expectations.
I can understand how a self-respecting string theorist might deplore the anthropic tendencies of his colleagues

but intellectually I do not take a position on it.

I do not anticipate much from string theory whichever way they go, whether they accept A.P. and try to get some benefit or whether they reject it. so I do not have an opinion about A.P.----it is just not an issue.

[Haelfix]

Well if SUSY were to fall, so would superstrings and everything derived from them. You would still have bosonic strings and string field theory.

But it would seem to me that LHC could only falsify low energy SUSY extensions of the standard model. Corrections, anybody?

Thats right, but much of the theoretical prejudice to like SUSY in the first place starts vanishing really fast as you push it to higher and higher energy. In fact, things get downright ugly (at the level of minimal SUSY), as you start having to do really nasty finetuning to make things work... Which defeats the original purpose. We might additionally have to rethink GUT theory...

Not to mention, there are atmospheric tests that will need an explanation.

Several other things will happen. Wimp based models based on the hope that SUSY will save them, will run into a dead end. At which point, we'll be stuck with some very unnappealing alternatives.

Imo it would be one of the bigger crisis's physics has undergone in recent history.. Larger even then the measurement of the Lamb shift.

[marcus]

... some of what I do understand of the objections by string theory's detractors looks unfair to me.

You may be mistaking being skeptical of string hype as being a "detractor".
I dont favor this school of quantum gravity or that. If string theory ever managed to predict a number, and they could put the theory on the line for real testing, I would be happy either way it came out.
It would be great to get some progress in quantum gravity.
But all I hear on that score is excuses and wishful thinking.

String theory has been way over-hyped and IMO has made limited progress since say 2001, while some of the alternative approaches have gotten little attention but have made considerable advances. (that would be an interesting thread topic! new QG results, progress since 2001)

I am not partisan to one alternative or the other, if Loop gravity fails and Simplex gravity succeeds, or viceversa, that is fine with me either way. Or if spin foam succeeds and the others fail.
If String would make a surprise comeback and turn out to be genuine theoretical physics (intead of an Elegant Mathematical Contruct) that would be wonderful too!

I try to report what is happening: the battle royal inside String, the decline in String papers, the decline in String citations, the progress in other lines of Quantum Gravity research, like Simplex, Foam, and Loops. (and Hawking seems to think also in Path Integral--his own non-string approach to quantum gravity).

Dont confuse reporting with detracting. If the muddle changes, and the string people get their act together, I will be delighted to report that. I find the main effort required is to cut through the hype Stringsters constantly put out: the lengthy litany of reasons why the newer alternatives have to fail, the "theoretical" reasoning is offered to prove that only string can succeed. They treat as sacred cow what is looking suspiciously like another failed attempt.

[marcus]

Peter Woit has been busy and some interesting comments have been
coming in from Thomas Larsson, Urs Schreiber, Arivero and others

Smolin on the Anthropic Principle
http://www.math.columbia.edu/~woit/blog/archives/000059.html

Polyakov: String Theory Is Crazy
http://www.math.columbia.edu/~woit/blog/archives/000058.html

Hawking in Dublin
http://www.math.columbia.edu/~woit/blog/archives/000057.html


some other memorable N.E.W. blogs

http://www.math.columbia.edu/~woit/blog/archives/000039.html

http://www.math.columbia.edu/~woit/blog/archives/000032.html

http://www.math.columbia.edu/~woit/blog/archives/000031.html

http://www.math.columbia.edu/~woit/blog/archives/000028.html

http://www.math.columbia.edu/~woit/blog/archives/000027.html


anyone who doesnt check Woit's blog regularly is missing a treat

[jeff]

You may be mistaking being skeptical of string hype as being a "detractor".
I dont favor this school of quantum gravity or that. If string theory ever managed to predict a number, and they could put the theory on the line for real testing, I would be happy either way it came out.
It would be great to get some progress in quantum gravity.
But all I hear on that score is excuses and wishful thinking.

String theory has been way over-hyped and IMO has made limited progress since say 2001, while some of the alternative approaches have gotten little attention but have made considerable advances. (that would be an interesting thread topic! new QG results, progress since 2001)

I am not partisan to one alternative or the other, if Loop gravity fails and Simplex gravity succeeds, or viceversa, that is fine with me either way. Or if spin foam succeeds and the others fail.
If String would make a surprise comeback and turn out to be genuine theoretical physics (intead of an Elegant Mathematical Contruct) that would be wonderful too!

I try to report what is happening: the battle royal inside String, the decline in String papers, the decline in String citations, the progress in other lines of Quantum Gravity research, like Simplex, Foam, and Loops. (and Hawking seems to think also in Path Integral--his own non-string approach to quantum gravity).

Dont confuse reporting with detracting. If the muddle changes, and the string people get their act together, I will be delighted to report that. I find the main effort required is to cut through the hype Stringsters constantly put out: the lengthy litany of reasons why the newer alternatives have to fail, the "theoretical" reasoning is offered to prove that only string can succeed. They treat as sacred cow what is looking suspiciously like another failed attempt.

I dont favor this school of quantum gravity or that. If lqg ever managed to predict a number, and they could put the theory on the line for real testing, I would be happy either way it came out.
It would be great to get some progress in quantum gravity.
But all I hear on that score is excuses and wishful thinking.

lqg has been way over-hyped and IMO has made limited progress since say 2001, while some of the alternative approaches have gotten little attention but have made considerable advances. (that would be an interesting thread topic! new QG results, progress since 2001)

I am not partisan to one alternative or the other, if strings fail and some other theory succeeds, or viceversa, that is fine with me either way. Or if strings succeeds and the others fail.
If lqg would make a surprise comeback and turn out to be genuine theoretical physics (intead of an Elegant Mathematical Contruct) that would be wonderful too!

I try to report what is happening: the dissolution of lqg, the decline in lqg papers, the decline in lqg citations, the progress in other lines of Quantum Gravity research, like strings.

Dont confuse reporting with detracting. If the muddle changes, and the lqg people get their act together, I will be delighted to report that. I find the main effort required is to cut through the hype lqger’s constantly put out: the lengthy litany of reasons why the newer alternatives have to fail, the "theoretical" reasoning is offered to prove that only LQG or some theory other than strings. They treat as sacred cow what is looking suspiciously like another failed attempt.

All joking aside though, the difference between strings and the other approaches is that the difficulties in the latter are actually fatal.

[arivero]

All joking aside though, the difference between strings and the other approaches is that the difficulties in the latter are actually fatal.

Is there a non-go theorem, thus?

[selfAdjoint]

A good discussion starting over at Not Even Wrong (http://www.math.columbia.edu/~woit/mt/mt-tb.cgi/72 ) on whether the quantisation prescription in LQG is really pukka. Smolin started off with an email to Woit making the same claims for LQG that he does in the paper we've been reading. Then Urs Schreiber weighs in making the same claim that LQG quantisation is deficient, or at least not standard, that he made in the aftermath to Thiemann's string quantisation paper.

Basically his point is that "canonical quantisation" means you transform the p and q variables which span the phase space, into operators, and in the Ashtekar new variables approach to LQG one of the corresponding variables, the "magnetic" form, cannot be elevated to an operator because it becomes ill-defined. So the LQG people simply replace it with an operator that seems to them what the magnetic form coulda become if it woulda transformed meaningfully. Or so Urs says, reading their papers. I have not confirmed this for myself and I am eager to see what Smolin replies.

Then Urs says this procedure is itself ill-defined because there are many possible choices for the "reasonable" operator. Or at least you have to prove that there aren't, which the LQG folks haven't done. Urs' point then is that this vitiates Smolin's repreated assertion that the the quantisation and uniquesness theorems are rigorous.

It would be really nice if somebody with real chops from the Ashtekar school, like Thiemann or Sahlmann, could get into this discussion. But we take what we can get. Urs is also pursuing some related topics at the String Coffee Table.

[sol2]

It is interesting to see Peter softening. :smile:

[marcus]

Hi selfAdjoint, sol.
Urs comment puzzled me because it did not engage what Smolin was talking about in his letter.

In the email Smolin says:
A key result is the LOST uniqueness theorem which shows that for d >=2 the hilbert space LQG is based on is the UNIQUE quantization of a gauge field that carries a unitary rep of the diffeo group, in which both the wilson loop and non-abelian electric flux operator are well defined operators. (see the paper and references for the precise statement).

this is a clear reference to some papers by Lewandowski Okolow Sahlmann and Thiemann.

but Urs acts as if he does not know what he is talking about and does not mention these papers or give links to any of them.

Instead he talks about something different: a paper that has been discussed
some months back by Ashtekar, Josh Willis. At one point Josh Willis came to SPR and had what looked to me like an inconclusive exchange with Urs concerning this paper. One could go back and look at it. But what puzzles me is the the disconnect with the L-O and S-T papers.

these are somewhat abstract and I do not recall Urs ever discussing them

Smolin's assertion of uniqueness refers to the uniqueness theorem for A-L measure and a certain representation I would guess, there has been a recent paper about this by yet a fifth person IIRC.

Urs should check the papers out and direct his comments at what Smolin was talking----not make distractive noises off in some other direction with links to papers Smolin was not talking.

selfAdj, thanks for the clarification!

maybe YOU can connect logically what Urs and the KaffeeKreis are saying to the LO-ST papers, earlier ones of which we were reading last year at PF
(or making our best efforts to:smile:)

A good discussion starting over at Not Even Wrong (http://www.math.columbia.edu/~woit/mt/mt-tb.cgi/72 ) on whether the quantisation prescription in LQG is really pukka. Smolin started off with an email to Woit making the same claims for LQG that he does in the paper we've been reading. Then Urs Schreiber weighs in making the same claim that LQG quantisation is deficient, or at least not standard, that he made in the aftermath to Thiemann's string quantisation paper.

Basically his point is that "canonical quantisation" means you transform the p and q variables which span the phase space, into operators, and in the Ashtekar new variables approach to LQG one of the corresponding variables, the "magnetic" form, cannot be elevated to an operator because it becomes ill-defined. So the LQG people simply replace it with an operator that seems to them what the magnetic form coulda become if it woulda transformed meaningfully. Or so Urs says, reading their papers. I have not confirmed this for myself and I am eager to see what Smolin replies.

Then Urs says this procedure is itself ill-defined because there are many possible choices for the "reasonable" operator. Or at least you have to prove that there aren't, which the LQG folks haven't done. Urs' point then is that this vitiates Smolin's repreated assertion that the the quantisation and uniquesness theorems are rigorous.

It would be really nice if somebody with real chops from the Ashtekar school, like Thiemann or Sahlmann, could get into this discussion. But we take what we can get. Urs is also pursuing some related topics at the String Coffee Table.

[sol2]

Just a link (http://www.math.columbia.edu/~woit/blog/archives/000072.html) correction in Self Adjoint's post, and of quote in Marcus's post.

By Lee's own statement and question(about it's qualification as a measure of quantum geometry, one has to ask how he might figure topological relevances to LQG interpretations could have any value as the discrete measures are limited to a range in Glast determinations?

Does this make sense? :confused: :smile:

[marcus]

It is interesting to see Peter softening. :smile:

Hi sol, the big change that I see is not a "softening" toward LQG but simply registering it at all. Peter has hardly acknowledged the existence of Loop till now.

He has simply been a critic of String, from a straight mathematical physics perspective. If he had noticed Loop he probably would have criticized it too!

There has been a huge change brought about by Smolin recent paper
"Scientific Alternatives..."

this paper has got Peter's attention because of its postion in the debate over Anthropy

suddenly Peter has acknowledged that Loop exists and is part of the picture and has even quoted Smolin email

this is how I see it.

-----------------------
I have a criticism of your viewpoint sol:

It seems to me that you constantly look at things as if there are two Camps (loop and string) between which peace must be made so that a higher synthesis or something can emerge.

I dont think that is quite the right historical model.

I cant tell you what historical paradigm to use.

But the strongest and most telling critiques of string have always come from people like Woit and Sheldon Glashow who are by no stretch of the
imagination in the "Loop Camp". (thinking of Glashow as in the LQG camp is ludicrous)

-----------
the discussion between looper and stringer concerns whether or not
String is the Only Game in Town or whether Loop can be recognized as a possible alternative approach. People like Lubos Motl repeatedly suggest that string is Destined to be the solution and all the other approaches to quantum gravity have Fatal Flaws. this is a mystical perception and a kind of faith. If that mystical vision prevailed at the NSF-NAS level then you could not do Loop in the USA---you'd have to go to Canada or Mexico or Germany or France or India etc. (this is almost the case now!)

so String is "beset" on two sides: on the one side is a little guy who keeps tugging at your sleeve wanting simply to be recognized as a potentially valid approach to quantum gravity and whom Lubos keeps beating up.

On the other side is a portion of the High Energy Physics establishment which is worried by certain self-indulgences and unempirical fantasy-land tendencies they see in String. This could eventually have an unfortunate effect of bringing discredit on the HEP establishment. So they dont even recognize that Loop exists---he is just this little guy who appears now and then and gets run off by Lubos. They are concerned with house-cleaning.
Susskind is a kind of dust-devil that bothers the hell out of them.

So the solution is not to make peace between Loop and String---that is a side issue. Ultimately (besides waiting till Susskind gets tired and can somehow be somewhat muted) the resolution must be
to bring String as fast as possible to a point of making some testable predictions. Read Peters blog-----basically he is always saying "LHC is almost ready to go! When are you guys going to make an unequivocal prediction about the $64,000 SUSY? When are you guys going to predict anything definite that LHC could test?"

When a new machine nears completion it a timehonored custom for the theory crowd to prepare a prediction (by which some theory lives or dies) to test in the machine. If they dont, then all right-thinking people are scandalized. Look! We pay 1000 string theorists to make theory. Look!
we build these expensive toys just so their theory can be tested! what is
happening! (the predictions have to come BEFORE the experiment otherwise science is not done.)

So I seriously challenge your suggestion that Peter is softening.
I dont think you will see him softening towards String (until and if it predicts something, which it certainly might do)

and I dont think his attitude towards Loop is softening so much as simply
acknowledging it as an alternative that possibly makes testable predictions.

Read smolin's "invitation" and you will see that almost the whole point is the fact that Loop is entering the stage where it makes testable predictions. read the "nearterm experimental situation"

Read smolin's "scientific alternative" and you will see that the whole point is the testability. you can have a Multiverse model which makes testable predictions and is thus a legitimate part of empirical science.

the testability is what is threatening to Susskind and is what those who feel threatened may wish to deny

Smolin and his friend are also under a rigorous time pressure. If GLAST flies by 2007 they [b]must have made predictions before then[b] because after the experiment it doesnt count. In "Invitation" Smolin explicitly says this---I can find the page if you want. he says to other physicists "we have this deadline, come on over and help us derive what to expect from GLAST".

the agenda is not making peace or what theory to believe---it's for amateurs to believe or disbelieve in theories---the issue is to get the sh*t in order so you can test a model. Anyway that's my perspective on the discussion at Peter's blog.

[sol2]

It seems to me that you constantly look at things as if there are two Camps (loop and string) between which peace must be made so that a higher synthesis or something can emerge.

Before you run off Marcus read post above yours again.


It seems to me that you constantly look at things as if there are two Camps (loop and string) between which peace must be made so that a higher synthesis or something can emerge.

No Marcus. I am trying to determine the limitations that each has figured theoretically might have been there respective downfalls, and I suspect I have found both these places :confused:

Read smolin's "invitation" and you will see that almost the whole point is the fact that Loop is entering the stage where it makes testable predictions. read the "nearterm experimental situation"

Thank you Marcus. I have come to enjoy Smolin's summations, becuase he is flexible to entertain all possibilties even though he is coming at it from a loop approach. Smolin included Penrose as one of the three.


Lubos contributing to wikpedia for Loop is another good example that fellows can do for us people who are trying see what roads to quantum gravity materialize.

And there are published predictions for observable Planck
scale deviations from energy momentum relations[22, 23] that imply predictions for experiments in progress such as AUGER and GLAST. For those whose interest is more towards formal speculations concerning supersymmetry and higher dimensions than experiment, there are also results that show how the methods of loop quantum gravity may be extended to give background independent descriptions of quantum gravity in the higher and super realms[31]-[35]. It thus seems like a good time for an introduction to the whole approach that may help tomake the basic ideas, results and methods accessible to a wider range of physicists.

http://arxiv.org/PS_cache/hep-th/pdf/0408/0408048.pdf
Of course it's still theorizing in bold by association? But trully, accepting the bulk as gravitons is not so far fetch? :smile:

So you can see where LQG is relying on SRian apporaches to help in this determination, but the graviton intersection, asks us to take it one step further. Of course we are limited here, and by this recogniton even LQG will suffer, falling short of describing the geometry of the quantum gravity? I have shown the interactive links in this way as respnse to Haelfix's continuing quest :smile:



Thanks

[marcus]

Just a link (http://www.math.columbia.edu/~woit/blog/archives/000072.html) correction in Self Adjoint's post, and of quote in Marcus's post.


Ho! thanks for correcting that link to Not Even Wrong!

[marcus]

Ah hah! Good quote from Smolin you just provided, sol!

"... there are published predictions for observable Planck
scale deviations from energy momentum relations[22, 23] that imply predictions for experiments in progress such as AUGER and GLAST...."

but there have to be more predictions and they have to be more vitally connected to the basic structure of the theory. experiments that can potentially test quantum gravity are few and far between

one wants to place as much of the theory at risk as possible so there is the maximum possibility for refutation.

then when GLAST flies one can say that in a certain sense "theory has been a guide to experiment"

when this happens it is the bar mitzvah day of theory, and it is doing what it is supposed to do


now I am feeling that maybe you and I see eye to eye on this, because of the Smolin paragraph you just quoted.

[sol2]

Ah hah! Good quote from Smolin you just provided, sol!

"... there are published predictions for observable Planck
scale deviations from energy momentum relations[22, 23] that imply predictions for experiments in progress such as AUGER and GLAST...."

but there have to be more predictions and they have to be more vitally connected to the basic structure of the theory. experiments that can potentially test quantum gravity are few and far between

if we falsify strings then it is good, and if we follow the logic of theory development, then predictions supported of LQG, is good :smile:

I believe Smolin holds this attribute in mind, and why his summation might have forced him to consider the reasons why he goes the way he does. Peter Woit would pick up on this as well I am sure, but the softness comes from the question in regards to the planck epoch to grand unification. Supergavity still has to be dealt with even if the understanding might issue from stringtheory. Supersymmetry has to be dealt with, and sure we can voice our opinions on the safe side, but until it is falsifiable, we are in a interesting position. Shall we all stop theorizing :rofl:

one wants to place as much of the theory at risk as possible so there is the maximum possibility for refutation.

Yes but how would you do this? By recognizing the limitations as I have said in one, but by the recogniton of the other. Holding these two views together, and in light of each othe,r helps one to discern the relevance of one from the other.

then when GLAST flies one can say that in a certain sense "theory has been a guide to experiment"

Absolutely. But, and this is the point that must be considered. It has its limitations too here.

So, LQG can go no further to describing the geometry of, and by answering this, you realize why string surpasses. The validation here in terms of Glast would move forward LQG in regards to a solid foundation experimentally, to the point of leading to supergravity. Lqg cannot go here.

Glast support of LQG would force strings to reconsider some of its work with regards to Lorentz invariance. We have spoken on this before.



now I am feeling that maybe you and I see eye to eye on this, because of the Smolin paragraph you just quoted.

In the sense, that support and validation, helps theoretical developement :smile:

Yes Marcus there are Peacemakers, with well intentioned views, to fuel the debate. To help us see the essence of things. Everyone wins :smile:

[marcus]

OK sol, now let's give selfAdjoint a chance to respond to my post #122
Urs seems to have made some misdirected criticisms of Smolin's email that did not actually connect with what Smolin was saying. Let's move the peacemaking discussion to another thread and get back to what just happened on Woit's blog. Peter posted an email from Lee and Urs challenged an assertion in the email whose basis he didnt seem to recognize (referring as he did to some completely different papers).


Urs comment puzzled me because it did not engage what Smolin was talking about in his letter.

In the email Smolin says:
A key result is the LOST uniqueness theorem which shows that for d >=2 the hilbert space LQG is based on is the UNIQUE quantization of a gauge field that carries a unitary rep of the diffeo group, in which both the wilson loop and non-abelian electric flux operator are well defined operators. (see the paper and references for the precise statement).

this is a clear reference to some papers by Lewandowski Okolow Sahlmann and Thiemann.

but Urs acts as if he does not know what he is talking about and does not mention these papers or give links to any of them.

Instead he talks about something different: a paper that has been discussed
some months back by Ashtekar, Josh Willis. At one point Josh Willis came to SPR and had what looked to me like an inconclusive exchange with Urs concerning this paper. One could go back and look at it. But what puzzles me is the the disconnect with the L-O and S-T papers.

these are somewhat abstract and I do not recall Urs ever discussing them

Smolin's assertion of uniqueness refers to the uniqueness theorem for A-L measure and a certain representation I would guess, there has been a recent paper about this by yet a fifth person IIRC.

Urs should check the papers out and direct his comments at what Smolin was talking----not make distractive noises off in some other direction with links to papers Smolin was not talking.

selfAdj, thanks for the clarification!

maybe YOU can connect logically what Urs and the KaffeeKreis are saying to the LO-ST papers, earlier ones of which we were reading last year at PF
(or making our best efforts to:smile:)
http://www.physicsforums.com/showthread.php?p=292877&posted=1#post292877

[marcus]

Here is the previous selfAdjoint post I was responding to.
A good discussion starting over at Not Even Wrong (http://www.math.columbia.edu/~woit/blog/archives/000072.html ) on whether the quantisation prescription in LQG is really pukka. Smolin started off with an email to Woit making the same claims for LQG that he does in the paper we've been reading. Then Urs Schreiber weighs in making the same claim that LQG quantisation is deficient, or at least not standard, that he made in the aftermath to Thiemann's string quantisation paper.

Basically his point is that "canonical quantisation" means you transform the p and q variables which span the phase space, into operators, and in the Ashtekar new variables approach to LQG one of the corresponding variables, the "magnetic" form, cannot be elevated to an operator because it becomes ill-defined. So the LQG people simply replace it with an operator that seems to them what the magnetic form coulda become if it woulda transformed meaningfully. Or so Urs says, reading their papers. I have not confirmed this for myself and I am eager to see what Smolin replies.

Then Urs says this procedure is itself ill-defined because there are many possible choices for the "reasonable" operator. Or at least you have to prove that there aren't, which the LQG folks haven't done. Urs' point then is that this vitiates Smolin's repeated assertion that the the quantisation and uniquesness theorems are rigorous.

It would be really nice if somebody with real chops from the Ashtekar school, like Thiemann or Sahlmann, could get into this discussion. But we take what we can get. Urs is also pursuing some related topics at the String Coffee Table.

If Lee is saying something about the LO and ST papers, and those results, and if Urs wants to vitiate it, as you say, then doesnt Urs need to examine and find something wrong with the LO and ST papers?
Just wondering :smile:

the was a new one in that line fairly recently. they strengthened the theorem. it was a May 2004 posting by Okolow and Lewandowski
http://arxiv.org/gr-qc/0405119

this summarizes the situation and extends the results. it would be the paper for Urs to try vitiating if he is anxious to vitiate something

[sol2]

I did not deviate from Peter Woit's thread (http://www.physicsforums.com/showpost.php?p=293009&postcount=128).

as I too, wave off your comment..... :smile:

and as to Self Adjoint's response....of course.

[selfAdjoint]

Hi selfAdjoint, sol.
Urs comment puzzled me because it did not engage what Smolin was talking about in his letter.

In the email Smolin says:
A key result is the LOST uniqueness theorem which shows that for d >=2 the hilbert space LQG is based on is the UNIQUE quantization of a gauge field that carries a unitary rep of the diffeo group, in which both the wilson loop and non-abelian electric flux operator are well defined operators. (see the paper and references for the precise statement).

this is a clear reference to some papers by Lewandowski Okolow Sahlmann and Thiemann.

but Urs acts as if he does not know what he is talking about and does not mention these papers or give links to any of them.

Instead he talks about something different: a paper that has been discussed
some months back by Ashtekar, Josh Willis. At one point Josh Willis came to SPR and had what looked to me like an inconclusive exchange with Urs concerning this paper. One could go back and look at it. But what puzzles me is the the disconnect with the L-O and S-T papers.

these are somewhat abstract and I do not recall Urs ever discussing them

Smolin's assertion of uniqueness refers to the uniqueness theorem for A-L measure and a certain representation I would guess, there has been a recent paper about this by yet a fifth person IIRC.

Urs should check the papers out and direct his comments at what Smolin was talking----not make distractive noises off in some other direction with links to papers Smolin was not talking.

selfAdj, thanks for the clarification!

maybe YOU can connect logically what Urs and the KaffeeKreis are saying to the LO-ST papers, earlier ones of which we were reading last year at PF
(or making our best efforts to:smile:)


Marcus, I think you are missing the point. All of the papers by Thiemann, Lewandowski, Ashtecar, and their coworkers quantize the Ashtekar variables in the same way, or so I recall, and so Urs says. And Urs says this quantization is defective, in the manner I explained. The fact that the the LOST paper proves uniqueness is fine and important. But it is worthless if the whole program is doomed, and it could be that unless this quantization problem is fixed, that there IS no LQG with the Ashtekar variables. That's why I want to hear from somebody on the LQG side, not about Smolin's claims, but about THIS problem.

[marcus]

Marcus, I think you are missing the point. All of the papers by Thiemann, Lewandowski, Ashtecar, and their coworkers quantize the Ashtekar variables in the same way, or so I recall, and so Urs says. And Urs says this quantization is defective, in the manner I explained. The fact that the the LOST paper proves uniqueness is fine and important. But it is worthless if the whole program is doomed, and it could be that unless this quantization problem is fixed, that there IS no LQG with the Ashtekar variables. That's why I want to hear from somebody on the LQG side, not about Smolin's claims, but about THIS problem.

thanks for replying. so for example we have this new paper in the LO bunch Lee referring to

sounds stupid to ask, but where is the step?

http://arxiv.org/gr-qc/0405119

this is by Lewandowski and Okolow and it came out in May

there is kind of mystique that Urs et al know what they are talking
but when I ask, for any particular paper that I am interested in, "where is the step you think isnt right?"

then I get an arrogant put-down or they start talking about some other paper by Thomas Thiemann or by Willis and Ashtekar.
if they really understand. if they really have a clear idea of what seems
different about the approach to quantizing
then they should easily point to the step in the sample I hold up
for inspection. that's all

maybe they can do it, but simply disdain to.

[marcus]

Another place where Urs could point out the step in quantization he has in mind is in


http://arxiv.org/gr-qc/0404018
Ashtekar Lewandowski
"Background Independent Quantum Gravity: A Status Report"

this is a 2004 patient rigorous development, combined with a review,
and it is about 125 pages

somewhere in the standard development on pages 24-40
there is a step which Urs can quickly point to if he knows
what he is talking about, I would suppose

instead we got something very disappointing from him, a reference
to a 2002 paper by Ashtekar, Fairhurst, Willis

Urs just is not showing enough consideration in his response. Look:

Smolin makes an assertion based on LO and ST papers.
the most recent is the 2004 one I linked.
http://arxiv.org/gr-qc/0405119
"Automorphism covariant representations of the holonomy-flux *-algebra"
by Mr. L and Mr. O.

If Urs has actually identified something novel in the approach to quantizing used in this paper I would love to know what it is, he can have a heyday pointing it out. this is a recent paper and part of a substantial advance in Loop. It would be valuable to know!

But sadly he does not, he goes and drags out a 2002 paper which was not what Smolin was basing his claim on.
He acts like he is responding to Smolin's claim without reading it and figuring out what work Smolin was referencing.

This kind of carelessness and arrogance is all too characteristic (and Urs is by far one of the nicer ones of that fraternity)

[marcus]

In case anyone is joining us here is the link to the discussion at
Not Even Wrong blog
http://www.math.columbia.edu/~woit/blog/archives/000072.html

it is pretty much at the top of the blog at the moment so if you just go to the usual

http://www.math.columbia.edu/~woit/blog/

you should see it.

there's a fairly interesting brief summary of where Loop is at the moment consisting of an email which Peter elicited from Lee and asked to put on the blog, and then there are comments from various and sundry Readers of the Blog.

as selfAdjoint said when he first called our attention to this bit of Woit action:
"A good discussion starting over at Not Even Wrong on whether the quantisation prescription in LQG is really pukka..."

I believe that pukka is a Kipling-Hindoo word for kosher as in
pukka sahib for respectable gentleman.

Here is selfAdjoint's initial post which states the Bone of Contention in succinct fashion

http://www.physicsforums.com/showthread.php?p=292773&posted=1#post292773

[marcus]

in desperation I am trying to guess what step Urs would say was novel
if he would look at one of the papers Lee referred to

so how about this:
Definition 3.4 of the flux operator on page 8,
of Lewandowski Okolow May 2004
http://arxiv.org/gr-qc/0405119

kind of nice paper, clear style
"Automorphism covariant representations of the holonomy flux *-algebra"

if anybody really knows what Urs means about something innovative in the approach to quantizing---and offensive to righteous tradition---maybe they can say if this Definition 3.4 is really it or not.
it would be interesting to know----maybe it really is novel and might even be good---mathematically seems kind of nice. but is it that which Urs would anathematise or something else?

[selfAdjoint]

thanks for replying. so for example we have this new paper in the LO bunch Lee referring to

sounds stupid to ask, but where is the step?

http://arxiv.org/gr-qc/0405119

this is by Lewandowski and Okolow and it came out in May

there is kind of mystique that Urs et al know what they are talking
but when I ask, for any particular paper that I am interested in, "where is the step you think isnt right?"

then I get an arrogant put-down or they start talking about some other paper by Thomas Thiemann or by Willis and Ashtekar.
if they really understand. if they really have a clear idea of what seems
different about the approach to quantizing
then they should easily point to the step in the sample I hold up
for inspection. that's all

maybe they can do it, but simply disdain to.

I have never seen anything arrogant from Urs. Maybe you are thinking of a couple of other guys. You keep talking about this paper which is rigorous, or that paper which shows how great LQG is, but you fail to come to grips with the objection, which is mathematical. Here is what Urs says in his first post at NEW:

When quoting results about uniqueness of the Hilbert space in LQG it must be emphasized that the quantization presciption used there is not what is usually called canonical quantization, and by this I mean differences over and above the ambiguities of canonical quantization itself. LQG uses 'relaxed' canonical quantization where not both of canonical coordinates and momenta are represented as operators on a Hilbert space.

He goes on to say that Thiemann and Ashtekar have both confirmed this "relaxed" quantization.

Now you want to be pointed to the exact statement in some linkable paper where that relaxed approach is stated. But the quantization argument in those papers is broken into a large number of segments, and the problem has to be fileted out. I have been reading the A&L paper you linked to and have some preliminary thoughts, but it will be a while before I can track the whole matter down, and frankly, I have other things going on in my life right now.

[marcus]

I have never seen anything arrogant from Urs. Maybe you are thinking of a couple of other guys. You keep talking about this paper which is rigorous, or that paper which shows how great LQG is, but you fail to come to grips with the objection, which is mathematical. Here is what Urs says in his first post at NEW:



He goes on to say that Thiemann and Ashtekar have both confirmed this "relaxed" quantization.

Now you want to be pointed to the exact statement in some linkable paper where that relaxed approach is stated. But the quantization argument in those papers is broken into a large number of segments, and the problem has to be fileted out. I have been reading the A&L paper you linked to and have some preliminary thoughts, but it will be a while before I can track the whole matter down, and frankly, I have other things going on in my life right now.

enjoy the other things, hope they go well

it seems unlikely then that anyone can simply look at definition 3.4 on
page 8 of this short paper by L and O and say "yes that is the definition I have doubts on, or seems novel" or "no, that is not it"

http://arxiv.org/gr-qc/0405119

that would be the best because it is what Smolin was referencing (the LO and ST papers) and it is a short clear paper.

I will look at A&L too, since you are----and try to guess what they are talking about. It might turn out to be a beneficial mutation, if it is real.

[marcus]

I have been reading the A&L paper you linked to and have some preliminary thoughts, but it will be a while before I can track the whole matter down, and frankly, I have other things going on in my life right now.

Since you are looking at A&L timepermitting, I had a look and have
identified the definition which apparently offends the Hidebound in THAT paper as well

I would guess it is (4.48) on page 39.

but again I cannot know Urs mind
the definition has the reassuring feature of being
adapted to poisson brackets of classical config. and momentum observables
which was calculated a few pages earlier on page 33
"As a prelude to quantization, let us calculate the Poisson brackets between these observables. Since the phase space is a cotangent bundle, the configuration observables have vanishing Poisson brackets among themselves...."
So then, 6 pages later, they are doing the quantum operators corresponding and I think it may be this (4.48) in which a germ of novelty is perceived.

Again it would be great to know----Loop has been shaping up well lately and if there is some innovation it might, as I say, be a benign mutation.
the trouble is I dont see a operational repeatable handle on what they are talking. Just Urs spin on what Urs says Thiemann told him or Ashtekar told him at a time when they were all in great uproar anyway.

[selfAdjoint]

I looked also at the 0405119 paper you suggested, but I don't think that paper is relevant to this discussion, because it is about extending Sahlmann's uniqueness theorem from the trivial bundle he worked with to a general principle bundle. As such it assumes the properties of the Sahlmann algebra and does not discuss the process of quantization as such.

A rereading of parts of the A&L paper suggests some attention to page 34. In Hamiltonian analysis the Poisson brackets of the P's with each other are supposed to vanish. But with the "electric fluxes" playing the role of the P, or momentum, variables, their Poisson bracket does not vanish. Instead A&L construct an algebra that supports this noncommutativity. Right here they have parted from "canonical quantization" and struck out into new territory. I won't have time tonight to see what they do with this further down in the paper, but I feel it must have some effect. I believe Urs would say this failure to commute signals an anomaly.