Blog Wars: Woit and Smolin vs Motl

[notevenwrong]

As for the claims from "Josh" that Lubos Motl is a great source to learn from, people might want to look into Lubos's posting earlier today claiming that the results announced by Miniboone confirm those of LSND. Most string theorists find Lubos to be a huge embarassment to their field, at more than one blog run by string theory partisans all posts that even mention Lubos are automatically deleted.

I have no idea who "Josh" is or why he is hiding behind a pseudonym. His claims that he has repeatedly tried to engage me in serious discussion about string theory and I've been unable to discuss this physics are nonsense. If he has an example to point to of this, he should do so. This is true no matter what pseudonym he uses on my blog.

It's a rather remarkable phenomenon that so many string theorists hide behind the cover of anonymity when making personal attacks on me and anyone else who disagrees with them. It also saves them from anyone looking into their qualifications to judge their credibility, and from any embarassment when they lose a scientific argument.

Peter

 

[marcus]

Josh is the pseudonym of Jeffery Winkler who you doubtless know from way back---when you were both posting on Sci.physics.research, like in 2003. John Baez may also remember Jeff from those days, since he was SPR moderator at the time.

 

[josh1]

Hi Peter,

It's a rather remarkable phenomenon that so many string theorists hide behind the cover of anonymity when making personal attacks on me and anyone else who disagrees with them. It also saves them from anyone looking into their qualifications to judge their credibility, and from any embarassment when they lose a scientific argument. Peter

Given how you've already been taken to task by some of the worlds best theorists, both publically and privately, it's strange that you'd come here and attack some "unqualified" and "anonymous" member of a forum whose purpose is mainly recreational. What's the matter peter? You sound a bit unhappy.

Is willfully not correcting people when they mistakenly refer to you as some kind of expert on string theory when your really just a math instructor hard on your conscience?

I have no idea who "Josh" is or why he is hiding behind a pseudonym. His claims that he has repeatedly tried to engage me in serious discussion about string theory and I've been unable to discuss this physics are nonsense. If he has an example to point to of this, he should do so. This is true no matter what pseudonym he uses on my blog.

It's kind of hard to point to examples when you simply refuse to post questions you don't or can't answer no matter how politely they're asked.

As far as lubos is concerned, he's your intellectual superior by many orders of magnitude. Even when he's wrong, at least he explains in detail what he's talking about. In this sense, his opinions are - if I may be allowed to put it this way - "falsifiable". This is not the case with you however. As I've already posted here, your site is meant to appeal to laymen or idiotic sycophants who can be easily manipulated. Lubos's remarks on the other hand are meant for other physicists.

In any event, I seem to have the ability to upset you. I'll keep that in mind.

 

[josh1]

Josh is the pseudonym of Jeffery Winkler who you doubtless know from way back---when you were both posting on Sci.physics.research, like in 2003. John Baez may also remember Jeff from those days, since he was SPR moderator at the time.

Bad idea mar***.

 

[Chronos]

That's quite interesting. Please, could you give any details or references (perhaps it would be appropriate to open a new thread)? I know about specially organised observations of high-redshift objects to detect quantum fluctuations of space. But you are talking about something different: an attempt to verify the quantized nature of spacetime, aren't you?

Yes, and I should have mentioned GLAST, not the Planck mission [Planck state of mind thing], as the gold standard. High frequency photons should be slightly delayed if spacetime is quantized, and GRB's are convenient sources.

 

[ZapperZ]

it appears that the "blog wars" and the mudslinging have been successfully moved to here. I will REMIND EVERYONE to go re-read the https://www.physicsforums.com/showthread.php?t=5374" once again, and if your word means anything at all, you will cease this bickering immediately or direct actions will be taken against you and this thread.

Zz.

 

[vld]

Yes, and I should have mentioned GLAST, not the Planck mission

Many thanks, Chronos. Among the GLAST publications I have immediately found those which you have in mind, e.g. astro-ph/0610571 .

 

[Leopold Infeld]

it appears that the "blog wars" and the mudslinging have been successfully moved to here. I will REMIND EVERYONE to go re-read the https://www.physicsforums.com/showthread.php?t=5374" once again, and if your word means anything at all, you will cease this bickering immediately or direct actions will be taken against you and this thread.

Zz.

Yes, you guys should stop bickering. The other time I posted something about string theory in the LOUNGE , two replies were all I got before my post was locked. Somebody suggested that I should post in this forum (Beyond the Standard Model). Then before knowing my post had been locked, I went to post in this forum for which I got an infraction. :rofl: :rofl:

Ever since then I had been afraid to post at all, but seeing Josh's reaction, my courage seem to have perked up :rofl: :rofl:

 

[Bohr_Wars]

Zapper, I take your point. I'm sorry if I have started something unpleasant here. My point in starting the thread was to ask why there is such anger and dispute on a matter of theoretical physics.

It's amazing that a question about which the general public has little understanding can make that same public wish to come down on one or other side of the string theory fence, as though they were choosing a football team or deciding whether sushi is better than tacos. I guess it's the power of the popular science books, plus the appeal that cutting-edge science now has over the reading public's imagination.

I have thoroughly enjoyed reading all the popular books, and I went to the blogs for more information. Personally, I find Woit's blog to be informative. It's tone is never aggressive. Motl's blog, on the other hand, though it is fun and sometimes informative, is often insulting of other researchers, thinkers and non-string theory approaches. This, as an outsider, surprises me. I wonder why there's the need for mud-slinging. Has it to do with the science, or is it merely personal issues? I guess it's a mad mixture of both.

 

[josh1]

Zapper, I take your point. I'm sorry if I have started something unpleasant here.

Dude, you did NOTHING wrong! I apologize if I made you feel as if you had.

 

[marcus]

.. My point in starting the thread was to ask why there is such anger and dispute on a matter of theoretical physics.
...

I personally haven't participated much in your thread, but I certainly do not fault you for starting it! If your purpose was what you say, it is a valid question to ask about (why so much heat?)

To put it in perspective, maybe (I say maybe) there is really not as much heat as you suggest. Maybe this is just the impression created by one or a few "dramatizing" blogs

And as you mentioned, Woit's posts are actually rather low-temperature. I go there largely to get leads to information like about recent experiment reports, papers, seminar talks available online. It's been great---widescope, selective, cool--and many of the commenters are actually helpful. So that is not one of the self-dramatizing personality blogs as I see it. But there are those too.

Also about your question, what Kissinger said is to be remembered:
'Academic quarrels are so vicious because the stakes are so small!

That remark was from a time when academic quarrels were normally conducted inside academic circles and in restricted academic media channels.
But even then there were the public GREAT DEBATES like the Harlow-Shapely 1920 debate on cosmology (is the milkyway the whole universe or are their other galaxies off in the distance?)

I wouldn't butt in here except I hate to see you B.W. (newbie) apologize for starting what I think is a legitimate thread. It is about legitimate questions.
Is the debate about approaches to unification and quantum gravity too hot?
If so, how hot is it actually and why is it that hot?
Are there some real issues---or what I personally would consider real issues---or is it just histrionics and ego-projection?

Perhaps, as Kissinger's quip suggests, the real stakes are minor. Perhaps, as Princeton Nobel-laureate Philip Anderson reckons it, they are huge.
(Anderson sees threat to the 400-year Baconian tradition---the protocol that theorists should only put forward promptly testable theories, and that there are no excuses). I don't want to suggest that I personally regard the stakes as either trivial or at the other extreme historical. Just to indicate a range of what I think are legitimate views.

 

[Bohr_Wars]

Marcus, I was reading Paul Davies the other day. He suggested there has been a big shift in recent years towards a public interest in scientific research. He dates it back to the publication of Stephen Hawking's first popular book. Until that time, intellectuals were considered to be people like film and literary critics, philosophers, theologians, social scientists. Scientists were thought of by the public as rather boring people who measured stuff, did a bit of estimating and forecasting. (Everyone knew that Einstein was something greater than that, but they didn't bother to read or understand his theories, or they were ill-equipped to understand relativity).

The old intellectuals were angered by the huge reception to Hawking's book. Suddenly a scientist was talking about big issues, the beginning of time, and making the subject sexy.

That's pretty much the picture today. I think we have stopped expecting philosophers and lit.critics to have exciting ideas, and we don't think they'll say anything surprising. The exciting stuff is happening in science: extra dimensions, strings, branes, loops, DSR, twistors.

Unfortunately, most of us have to play long and difficult games of catch-up to understand the math. We are utterly dependent on popularizations for forming our opinions. Add to that the internet, blogs, Physics Forums, etc, and so much more information is available and immediate.

There are down sides to that. For example, Motl, who might be a calm and charming guy among friends and colleagues, acquires an internet persona as a ranting fist-fighter, causing the unitiated to form their opinions on scientific matters on the basis of Motl's humor and anger. They like string theory because Motl takes no prisoners and seems not to like bs.

These peripheral issues might well affect the science itself, ie all the work that goes on away from blogs and the public and media eye. Folks who decide to give money to research programs, or students thinking of which subject to study, or which grad school to attend, might have their opinions shaped in some way by the wider debate. String theory can seem to be a very exciting and promising area because so many people outside string theory are talking about it. Then along comes a Smolin or a Woit and tells us the theory isn't that great, which causes more of a storm and more interest in science. Fascinating stuff, I think.

 

[marcus]

B_W,
the stated purpose of your thread, as I see it, is good.
Maybe there should be a new thread about these questions---what is actually at stake? What do we think the discussion being carried on by our wiser-and-betters about these issues? If it has gotten out of hand and isn't constructive, then why? (the last is what you specifically asked...why all the heat?)

The TITLE of your thread was a bit sensational, which might be OK or might not be so OK. At least it gets action and draws participants.

We could either USE this thread and try for a cool discussion. Or we could try starting a new thread without redflag words ("war") and boxoffice names in the title. Either course of action is risky. Any thread about these things, no matter how you title and initiate it, can go haywire and lead to bickering.

 

[marcus]

Marcus, I was reading Paul Davies the other day. He suggested there has been a big shift in recent years towards a public interest in scientific research. He dates it back to the publication of Stephen Hawking's first popular book. Until that time, intellectuals were considered to be people like film and literary critics, philosophers, theologians, social scientists. Scientists were thought of by the public as rather boring people who measured stuff, did a bit of estimating and forecasting. (Everyone knew that Einstein was something greater than that, but they didn't bother to read or understand his theories, or they were ill-equipped to understand relativity).

The old intellectuals were angered by the huge reception to Hawking's book. Suddenly a scientist was talking about big issues, the beginning of time, and making the subject sexy.

That's pretty much the picture today. I think we have stopped expecting philosophers and lit.critics to have exciting ideas, and we don't think they'll say anything surprising. The exciting stuff is happening in science: extra dimensions, strings, branes, loops, DSR, twistors.

Unfortunately, most of us have to play long and difficult games of catch-up to understand the math. We are utterly dependent on popularizations for forming our opinions. Add to that the internet, blogs, Physics Forums, etc, and so much more information is available and immediate.
...

this post is very interesting. I didnt see it when I wrote earlier. I'll need to think, maybe be some hours before I get back to these ideas and can respond

 

[josh1]

Unfortunately, most of us have to play long and difficult games of catch-up to understand the math. We are utterly dependent on popularizations for forming our opinions. Add to that the internet, blogs, Physics Forums, etc, and so much more information is available and immediate.

Yes. And given that "utter" dependency, the question of who - if anyone - should one trust becomes very important. Indeed, the reason we attend lectures to take notes in college is because although we could just read a bunch of textbooks, it makes more sense to have an expert tell us what is important to know.

...Motl, who might be a calm and charming guy among friends and colleagues, acquires an internet persona as a ranting fist-fighter, causing the unitiated to form their opinions on scientific matters on the basis of Motl's humor and anger.

Yes. So the people who actually know him personally see him very differently. For example, woit says that physicists are embarrassed by lubos. But then how do you explain the fact that there where two major books on string theory released this year, and the authors saw fit to include motl's endorsement, along with top people including witten, polchinski, vafa, strominger, arkani-hamed, seiberg, green, and swartz on the covers of each of them. In fact, there is another major string theory textbook about to be released by princeton university press and motl is again on the cover as an endorser. I mean, how much of an "embarrassement" could motl actually be?

They like string theory because Motl takes no prisoners and seems not to like bs.

I'm not sure how influential motl is, but given his encyclopedic knowledge of the subject, you'll come away with a much more accurate view of string theory from his blog then from woit's.

 

[ccdantas]

(...) the reason we attend lectures to take notes in college is because although we could just read a bunch of textbooks, it makes more sense to have an expert tell us what is important to know.

Hm. I wouldn't phrase it that way. I'd probably say that "it makes more sense to deeply think over about what an expert tell us what he thinks is important to know".

From my personal experience, blogs do amplify things.

But the debate around string theory is interesting for several reasons, which have been scrutinized over and over elsewhere.

One thing that I find obvious, but it is my personal view of course, is that the debate is not about winners and losers. It's mostly about a fight for limited resources, and how the scientific activity is conducted in our era.

Winners x losers is one strong paradigm of the american society, and I often find it funny from my latin american perspective. Yes, it can lead to useful achievements in some aspects, but not always. And I don't see scientists as winners or losers. Great scientists had their moments of discovery and failure.

As much as Nature "does not care" about the coordinate system one uses (so that the physical theory should be independent of any coordinate system), she "does not care" about such an anthropocentric view of "winners and losers". Just because most high energy physicists are working on string theory this does not mean they are "winners" in the correct path.

I think string theory is a high achievement in many senses and research in this area should continue to be promoted. But there is yet not a clear, undisputable argumentation that string theory is the right path. There could be elements of it in the right path. Or it could be wrong.

It seems highly strange to me that other approaches -- under the hypothesis that they are based on reasonable and testable assumptions -- should be considered as "loser approaches". This is not how scientific advancement should proceed. At least, not in my view. These other approaches -- again, as far as they offer interesting and reasonable material for investigation -- should be promoted as well. Why not?

This is quite obvious to me, but as I said, the problem is about resources and how science is practiced nowadays. :yuck:

I run a blog during one year and I felt myself suddenly in the middle of war that made no sense to me and I got tired, bored, and lost sleep. Yes, blogs amplify things. And scientists should have a responsability for what they write in their blogs because at the same time that things can be entertaining (I confess that I laughed to myself many times around the blogosphere), others might turn out to be damaging to the laymen and interested readers, not to say to professional colleagues, who are often called crackpots. Just absurd.

Christine

 

[josh1]

Hm. I wouldn't phrase it that way. I'd probably say that "it makes more sense to deeply think over about what an expert tell us what he thinks is important to know".

Nobody is saying that you shouldn't consider carefully what you've learned. I'm just saying that if you're interested in learning about something, starting with the mainstream ideas makes more sense then beginning with ideas that are less conventional. My annoyance comes from some people who try to willfully mislead others about what are the mainstream ideas. LQG is not the mainstream, string theory is, so that’s where people should begin.

…the debate is…mostly about a fight for limited resources, and how the scientific activity is conducted in our era.

Whatever the debate is about, it takes place much more in the public then the professional arena and isn’t important because the kind of science we’re talking about has no practical implications for human beings. Again, other’s try to mislead here by arguing that scientists should base their decisions on what to study according to the sales of popular books on science.

…there is yet not a clear, undisputable argumentation that string theory is the right path. There could be elements of it in the right path. Or it could be wrong.

No argument there. But even if string theory is dead wrong, we should be honest about the fact that it is still the mainstream approach.

It seems highly strange to me that other approaches -- under the hypothesis that they are based on reasonable and testable assumptions -- should be considered as "loser approaches". This is not how scientific advancement should proceed. At least, not in my view. These other approaches -- again, as far as they offer interesting and reasonable material for investigation -- should be promoted as well. Why not?

Nobody is forbidding people from working on other approaches. But there are fundamental theoretical reasons why most physicists believe that the basic difficulties with these other approaches are insurmountable. As far as how science should advance, don’t worry about it. It will advance no matter what your views on the subject are.

…tired, bored, and lost sleep.

I never get bored.

 

[ccdantas]

As far as how science should advance, don’t worry about it. It will advance no matter what your views on the subject are.

Yes. Science advanced before me and will (probably) advance after me. I never claimed my views would have any role in the advancement of science. And, evidently, anyone who claims such a thing is a fool.

I never get bored.

You're lucky. I get bored with repetitiveness.

 

[Bohr_Wars]

There are so many areas of important scientific and medical research that barely get a mention in the popular press. So it's odd that physics at its most theoretical and obscure, ie string theory, has been able to capture the public's attention.

I was recently asked by someone who knows even less math than I do, "Are you for or against string theory?" That's fun, as though it makes a difference what one thinks one way or the other, as though we are qualified to make a judgement. String theory has become a topic of conversation, much like any mundane subject one might talk about.

Strings, and other competing theories and ideas, have worked their way into pop culture thanks to Brian Greence, Lee Smolin, Lisa Randall, Peter Woit, etc, not to mention the dreaded Motl blogs. I haven't a clue whether that's good, bad, or it doesn't matter a fig. But it's a remarkable achievement.

 

[marcus]

Marcus, I was reading Paul Davies the other day. He suggested there has been a big shift in recent years towards a public interest in scientific research. He dates it back to the publication of Stephen Hawking's first popular book. Until that time, intellectuals were considered to be people like film and literary critics, philosophers, theologians, social scientists. Scientists were thought of by the public as rather boring people who measured stuff, did a bit of estimating and forecasting. (Everyone knew that Einstein was something greater than that, but they didn't bother to read or understand his theories, or they were ill-equipped to understand relativity).

The old intellectuals were angered by the huge reception to Hawking's book. Suddenly a scientist was talking about big issues, the beginning of time, and making the subject sexy.

That's pretty much the picture today. I think we have stopped expecting philosophers and lit.critics to have exciting ideas, and we don't think they'll say anything surprising. The exciting stuff is happening in science: extra dimensions, strings, branes, loops, DSR, twistors.

Unfortunately, most of us have to play long and difficult games of catch-up to understand the math. We are utterly dependent on popularizations for forming our opinions. Add to that the internet, blogs, Physics Forums, etc, and so much more information is available and immediate.
...
...tells us the theory isn't that great, which causes more of a storm and more interest in science. Fascinating stuff, I think.

this post of B_W, #47, is still unreplied. it was nominally to me but I didn't have a ready answer. Anyone feel free to respond to the issues raised.

The root idea apparently comes from a book by Paul Davies (I haven't read).
B_W or anybody feel free to list some titles of Davies or cite chapter and verse. Copy and paste anything that gives a handson feel for what you are talking about.

I will try to paraphrase, or put in my own words. The following attempt to respond ot B_W post is based on my own guesswork vision.

 

[turbo]

As much as Nature "does not care" about the coordinate system one uses (so that the physical theory should be independent of any coordinate system), she "does not care" about such an anthropocentric view of "winners and losers". Just because most high energy physicists are working on string theory this does not mean they are "winners" in the correct path. Christine

This is an important concept IMO, that is often overlooked. The universe does what it does regardless of whether we are here or not, and just because we humans overlay coordinate systems on it in order to try to express what it does in mathematical terms, that should not imply that the coordinate system has some sort of independent reality or importance, apart from the theory that requires its implementation in order to be predictive.

Modern cosmology bothers me. The more convoluted a cosmological theory is, the more likely it is to be wrong because nature cannot follow a complex set of rules and remain so wonderfully consistent everywhere and everywhen we look. Chess has few rules, but it can be one of the most complex mind-bending games to play. Similarly, I believe that nature has very few rules and that the complexity we see around us is the result of the natural interplay of matter and energy within those simple rules. Some might consider this view philosophical in nature, but I believe that it is pragmatic and realistic.

 

[marcus]

here's my sort of paraphrase of post #47

human societies tend to canonize or sanctify some group of "guru" or "magus" or philosopher-priesthood who tell them stories which address their ultimate concerns like
why is there life?
and will there always be life?
and what is the sun?
and what are the stars there for?
and are giraffes and elephants for real?

and different elites can get into turf-wars where they elbow and crowd for centerstage and compete to see who tells the best stories.

the Peace of Galileo was negotiated in the 1600s and is based on Scientists not being aggressive so the Scientist elite can discover and tell each other marvelous stories that explain all sorts of things and have wonderful highly graphic imagery, but they restrain themselves from getting in the way when the Biblical folks are telling their stories (which are also very dramatic and beautiful).

The Church(es) had to settle for that because they were busy with the Reformation at the time (1618 Defenstration of Prague start of 30 years war, terrible awful fights betw. Prots and Caths). The religious authorities had their hands full with in-house conflict, so they settled for peaceful coexistence with Science. This became the customary mode of decorum, the entrenched standard attitude.

The Scientific method of Francis Bacon was also described in detail around the same time 1620. (title of 1620 book Novum Organum means "a new instrument", he was an elizabethan and contemp of shakesp).

OK so we have had about 400 years of a kind of CEASEFIRE where we make a point of NOT seeing who tells the best stories. and we do NOT try to upstage each other.

As I see it, what B_W tells us that Paul Davies says is that this sort of 400 year truce is BREAKING DOWN.
Also I see that Paul Davies is making money from this.
https://www.amazon.com/exec/obidos/...ks&field-author=Paul Davies&tag=pfamazon01-20
Cosmic Jackpot: Why Our Universe Is Just Right for Life by Paul Davies
Mind of God: The Scientific Basis for a Rational World by Paul Davies
The FIFTH MIRACLE: The Search for the Origin and Meaning of Life by Paul Davies
God and the New Physics by Paul Davies
The Last Three Minutes: Conjectures About the Ultimate Fate of the Universe by Paul Davies
The Ghost in the Atom: A Discussion of the Mysteries of Quantum Physics by Paul Davies and J. R. Brown
The Matter Myth: Dramatic Discoveries That Challenge Our Understanding of Physical Reality by Paul Davies and John Gribbin
Are We Alone?: Philosophical Implications of the Discover of Extraterrestrial Life by Paul Davies and P. C. W. Davies
Science and Ultimate Reality: Quantum Theory, Cosmology, and Complexity by John D. Barrow, Paul C. W. Davies, and Jr, Charles L. Harper

(one of the reasons it is breaking down is that prestige scientists can make money doing the story-teller act where they tell the populace about the big questions and the ultimate concerns---there is an economic motive)
I listed the titles of Davies books just to show you. But Hawking would also be an example.

And if you haven't visited the webpage of FQXi FOUNDATIONAL QUESTIONS INSTITUTE funded by TEMPLETON FOUNDATION, it would be instructive. People suspect that some Templeton billions are aimed at crashing down the neat, carefully maintained pickett fences between various science disciplines and
$$\mathfrak{religion}$$

 

[pelastration]

String theory has become a topic of conversation, much like any mundane subject one might talk about.

Strings, and other competing theories and ideas, have worked their way into pop culture thanks to Brian Greene, Lee Smolin, Lisa Randall, Peter Woit, etc, not to mention the dreaded Motl blogs. I haven't a clue whether that's good, bad, or it doesn't matter a fig. But it's a remarkable achievement.

BW,

Maybe it's very good marketing. Look how much is published. Every string expert published at least one book, to become mainstream popular, gain status and make extra money. Brian Greene had his own TV show. Interviews. It's big business; yes maybe playing on the human need to have some (religious) security, or at least the feeling to understand. And people who say that their theory was found by chance ... 50 years in advance ... aren’t they self-promoting their genius status? Whaw that must be a very, very smart guy thinking 50 years ahead! That deserves a Hollywood movie. Where is the contract?

 

[Bohr_Wars]

Marcus,
I've found the Paul Davies' quote. It's in his book, "About Time", p184. Davies writes about the response to Hawking's "A Brief History of Time":
"Especially outraged by Hawking and his daring ideas were the British chattering classes. By tradition, British intellectual life is dominated by the arts-and-literary fraternity... Indeed, scientists are rarely even afforded the status of 'intellectuals'. Science, to the extent that it is considered at all by British opinion-formers, is regarded as at best a necessary evil required to propel money-spinning technology, and at worst a technocratic conspiracy... The chorus of anger that rose in response to Hawking's book took the form of public denunctiation by self-righteous politicians and journalists... The feeble argument was trotted out that that any important truth ought to be transparent to all thinking people".

Davies is a physicist and prolific author.

 

[josh1]

...it's odd that physics at its most theoretical and obscure, ie string theory, has been able to capture the public's attention.

Is it odd? After all, it's human nature to wonder about the nature of reality and existence. So to the extent that the public understands that fundamental physical theories like string theory - which in particular they learn is a candidate theory of everything - are supposed to be sciences way of giving meaning to such things, they'll be interested.

 

[Bohr_Wars]

Josh,
The way you put it, no it's not odd at all. As you say, the theory/theories with claims to be the TOE are going to be of interest because they'll provide the foundation on which everything else is built. How much we understand of those theories is another matter.

 

[Careful]

This is an important concept IMO, that is often overlooked. The universe does what it does regardless of whether we are here or not, and just because we humans overlay coordinate systems on it in order to try to express what it does in mathematical terms, that should not imply that the coordinate system has some sort of independent reality or importance, apart from the theory that requires its implementation in order to be predictive.

You have to be very careful here : (a) when we do observations, we always endow coordinates with a *physical* meaning, that is we image our x,y,z axis to be *straight* lines with respect to an imaginary Minkowskian geometry, we can also put a priori restrictions upon the conformal factor (e.g. put it = 1 in these coordinates) of the ``real geometry'' for example ...
(b) Of course, the relational laws expressing our *observations* should be the same no matter which coordinate system has been chosen (but this invariance does not need to be *manifestly* present). However this does not preclude one from considering one coordinate system more real than another one (and rebuild the theory from there).

The whole ``quarrel'' is about wheter general covariance is something trivial or whether it is not : it goes between a worldpicture of spacetime atoms carrying non local relations amongst themselves and a picture of atoms traveling on a continuous background geometry. The thing is that the only more or less rigorous *classical* proposal for space time atoms that I am aware of and which recovers GR (at low energies) in a convincing way comes out of condensed matter physics (which uses a background).

 

[Chronos]

Long as it works, any coordinate system is fine. If they can't be interchanged, the problem is with the coordinate system, not physical reality.

 

[Careful]

Long as it works, any coordinate system is fine. If they can't be interchanged, the problem is with the coordinate system, not physical reality.

The point is that any theory can be made manifestly covariant, manifest covariance simply requires extra ``gauge degrees of freedom'' which results into constraints and into people wondering whether it is impossible to give an objective status to the evolution of the universe and whether the theory only allows for expressing relations between partial observables. On the other hand, the funny thing is that LQG as it stands now, does not even make proper work of the spacelike diffeomorphisms : although one does not meet the difficulty here that the constraints only generate diffeomorphisms on shell (such as is the case for the H constraint) and therefore diffeo invariance can be implemented at the kinematical level, one still needs implement the constraint itself (which is impossible since the action of the diffeo group is discontinuous).

 

[ccdantas]

The point is that any theory can be made manifestly covariant, manifest covariance simply requires extra ``gauge degrees of freedom'' (...)

Dear Careful,

I have read recently this paper by Weinstein

http://philsci-archive.pitt.edu/archive/00000834/

What do you think of his interpretation? He makes an interesting point, but it seems like there could be some contra-argumentation. I`m not sure. I appreciate any inputs.

(Perhaps we should start a new thread on this?)


Christine

 

[Careful]

Dear Careful,

I have read recently this paper by Weinstein

http://philsci-archive.pitt.edu/archive/00000834/

What do you think of his interpretation? He makes an interesting point, but it seems like there could be some contra-argumentation. I`m not sure. I appreciate any inputs.

(Perhaps we should start a new thread on this?)


Christine

Dear Christine,

I just gave one brief look so I might be wrong here : but I suppose the main criticism will be that gravity is not a gauge theory in the sense of what we usually mean with this (defined through fibre bundles). If I am correct, you should know that I agree here (all strict gauge theoretical attempts require the introduction of torsion - arriving therefore at Einstein Cartan theory which is not a bad thing btw), that is why I put ``gauge degrees of freedom'' between brakets. If you want to know what I actually was talking about, you might want to study the paper of Doran, Gull and Lasenby : ``Gravity, gauge theories and geometric algebra'' gr-qc/0405033.

 

[ccdantas]

If you want to know what I actually was talking about, you might want to study the paper of Doran, Gull and Lasenby : ``Gravity, gauge theories and geometric algebra'' gr-qc/0405033.

Thanks for the reference, I'll read it.


Christine

 

[George Jones]

Dear Careful,

I have read recently this paper by Weinstein

http://philsci-archive.pitt.edu/archive/00000834/

What do you think of his interpretation? He makes an interesting point, but it seems like there could be some contra-argumentation. I`m not sure. I appreciate any inputs.

(Perhaps we should start a new thread on this?)


Christine

You might want to look at https://www.physicsforums.com/showthread.php?t=164352".

 

[Careful]

You might want to look at https://www.physicsforums.com/showthread.php?t=164352".

Indeed, in the Doran, Gull and Lasenby paper, there is a clear separation between the usual local rotation symmetry and the nonlocal ``translation symmetry''. However, there is a large number of other benefits to it which are not mentioned in the post you refer to.

 

[john baez]

One thing that I find obvious, but it is my personal view of course, is that the debate is not about winners and losers. It's mostly about a fight for limited resources, and how the scientific activity is conducted in our era.

This is certainly part of the story. But, I think some of the anger surrounding the string wars comes from the desperation many theoretical physicists feel when it comes to making progress on big issues like the unification of forces and the quantization of gravity.

People have invested their whole careers in string theory and loop quantum gravity. Decades have gone by without any clear payoff in experimental results. Lots of good math, but no experimental confirmation! This makes people scared, and unhappy... and now, I think, it's making them fight.

Note how little fighting of this sort we see in cosmology, where people are making wonderful discoveries left and right: dark matter, dark energy, hints of inflation in the cosmic microwave background radiation.

I ran a blog during one year and I felt myself suddenly in the middle of war that made no sense to me and I got tired, bored, and lost sleep. Yes, blogs amplify things.

Blogs provide a brand new forum for uninhibited and often anonymous fighting, just at a time when a bunch of physicists are getting desperate and miserable... it's a flammable combination.

Like you, I got sick of these fights. They helped convince me it was time to stop working on quantum gravity and focus on math.

For a long time these fights also kept me from starting a blog. But then, thanks to Urs Schreiber, I realized it's possible to have a pleasant and interesting blog, by keeping it technical and avoiding controversy.

It's a pity I have to avoid writing about controversial topics just to avoid fights. But, it's worth it.