Dax discussions of Beyond SM theories/including newcomer questions

[petergreat]

Imagine Schrodinger, Bohr, Heisenberg et. al. developing QM before there was even a shred of proof that energy was quantized. Not only would it have been rather silly (c.f. my creationism cartoon), but I doubt it would even have been possible. How much more so is this true for far more complex modern physics?

If these people were smart enough, they could have developed quantum mechanics in 1870, when Mendeleev had already published his periodic table but well before the discovery of electrons, atomic nuclei, photoelectric effect, Balmer series and so on. After all, the periodic table encodes many elements of quantum mechanics, i.e. quantized nuclear charge, gradual filling of electron energy levels, fermi statistics restricting 2 electron per orbit, and existence of neutrons to make up missing atomic weights etc. Certainly the periodic table was a better hint towards new physics than today's dark energy.

So Even if experimental physics halted in 1870, these people could have worked out a theory compatible with all the features of the periodic table. If they were as clever as string theorists, they might even come up with a beautiful theory explaining these elements as Kaluza-Klein multiplets, or obtain a whole landscape of periodic tables!

 

[Lt_Dax]

The periodic table is an experimental result, and indirect evidence of quantization, isn't it?

 

[Kevin_Axion]

Ok, this will continue ad infinitum, let's just settle our differences and realize that they won't change by a mild debate amongst conflicting views.

 

[marcus]

... let's just settle our differences and realize that they won't change ...

I think we will choose not to, at this point, Kevin. Because the topic in Dax opener is the role of phenomena (observation, experiment, measurement, prediction...) in the development of physical theory. It is a general issue, more interesting than stringy specifics.

And some phenomenologists, possibly to the dismay of some Loop theorists, have recently determined LQG to be falsifiable by observation of the polarization in ancient light.

Some of these phenomenologists (whose past work has involved several other theories besides Loop) are Aurelien Barrau, Julien Grain, Wen Zhao. There are a half-dozen others who have co-authored with one or more of these in a series of papers.
https://www.physicsforums.com/showthread.php?p=2983268#post2983268
http://www.math.columbia.edu/~woit/wordpress/?p=3262&cpage=1#comment-67952

Zhao is at Cardiff, Barrau is at Grenoble (sometime CERN), Grain is at Paris.

What happened is kind of intriguing. The work of Ashtekar's Penn State group, and many others, has confirmed since 2006 that the bounce is a highly robust conclusion from Loop cosmology. Meanwhile a lot of bridges have been built between the full (spinfoam) LQG theory and the application to cosmology. One can even start with a simple spinfoam version of LQG and derive a bounce.

Possibly to some Loop theorists' surprise, Barrau and friends have determined that a Loop bounce must have a particular signature in the B-mode polarization of ancient light. It puts LQG at risk and is either interesting or exciting depending on one's moral character and point of view.

This may put several persons' noses out of joint and they may have nasty things to say about it ---scorn denial etc. We can't predict but it will be instructive to see the reaction. Someone will probably mention Lee Smolin, but this whole thing has nothing to do with Smolin or any of his current research. It is basically on Ashtekar and Rovelli's plate and you need to know their recent work to comment intelligently.

To summarize: The conservative Baconian stance taken in Dax opening post is pragmatically correct. And quantum gravity theory is going to move ahead in concert with experiment/observation whether you like it or not.

 

[marcus]

I have to go out for a while but will continue later.
Loop QG space is tending to become the space we use to talk about the early universe. You can see that with a simple keyword search of the Stanford/SLAC database of physics research papers. Recent "quantum cosmology"

There's a simple reason for this. I'll try to explain when I get back. It won't always necessarily be the quantum geometric framework for early universe---could be replaced by an improved version or something different! But that's the current trend and there's a reason to point out.
Back later.
============
I'm back.
The reason has to do with what Dax said in the first post. But this may not be immediately obvious. It's not because of presumed "rightness or wrongness"----we only have superstitions about that, can't presume to know future.

The reason is that LQG gives a mathematical representation of the geometry of the whole universe, that you can calculate with.
It has a Hilbert space of quantum states of geometry and a pathintegral or spinfoam way for them to evolve---simple enough to calculate with. And this is what cosmologists need.

It is what General Relativity gives you, a dynamic geometry instead of a fixed pre-determined one. You have to have this to do cosmology. Cosmology is the key to observation here (because our image of the early universe is enormously magnified by expansion.) The only trouble with GR being that it fails at the bang---it does not allow time-evolution to proceed back before the start of expansion. The spacetime geometry of GR is the basis for cosmology, so to go back into the very early you need a quantum geometry to take its place.

LQG is experiencing rapid growth now precisely because it provides a simple tractable model of the geometry of the early universe. One you can try out your ideas with. To a first approximation for practical purposes it doesn't matter whether right or wrong. The competition currently offers dubious handwave, or fixed pre-determined geometries, or ones based on GR that blow up at the start. Whatever they offer it seems not to be what the cosmologists are used to or find convenient to work with.

=======================

A rival approach could get in on this action by offering an appropriate quantum dynamical model of the geometry of the whole universe, to compete for some of LQG cosmology business. But I didn't hear of any competition yet, in practical terms that you can get your hands on and play around with.

=======================

The reason this is a valuable stimulus for Loop progress goes back to what Dax said. Early universe is our window on extreme physics. Theory needs to progress in concert with observation/experiment. Quantum gravity MEANS QUANTUM GEOMETRY and to connect to quantum geometry phenomena you need to provide a spacetime geometric home for the early universe.

This may seem roundabout but contemporary experience bears it out and if you listen to the chain of reasoning you will hear Empiricism talking and giving you her advice.

If you do a search of Spires HEP archive with keyword "quantum cosmology" for consecutive years you will see this rapid growth I am talking about. Loop gives the observational people a quantum geometry they can use.

Or so I think. That's how I interpret the past 4 or 5 years changes. You may have different explanations and understanding.
http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=dk+quantum+cosmology+and+date+%3E2006&FORMAT=WWW&SEQUENCE=citecount%28d%29

 

[Fra]

(I've been troubleshooting intermittently failing RAM modules for the last days and now finally found the bad one)

I sought some clarification of why it is justified to claim that in BTSM theories we are discovering new physics rather than merely hypothesizing.

I missed out the whole discussion and I'm not sure what the key question really was, but I too certainly wouldn't label "discovering" dualities in ambigously created theory spaces as "new physics". That's not to say it won't lead anywhere, but I think theoretical speculation is a better word.

It's more like a exploration of a specific theory space, construction and transformations of theories, where we find mathematical patterns and relations. Wether this has any physical significance is still an open question IMO, beucase the logic of inference applied when doing this is NOT unique. It's perhaps almost unique given certain premises; but that's the same thing. The basic premises and abstractions of ST (for example; although I agree this discussion isn't specific to ST) aren't objectively justified.

I don't think it's not necessarily bad with speculations, mathematical or philosophical - they are needed - but one must still be fair and not confuse these things with the physics content.

/Fredrik

 

[suprised]

I'm tiring of this. If you actually believe that the criterion for accepting an idea in science is mathematical proof, whereas I believe it is experimental validation, then it is no wonder we are talking past each other.

No I didnt mean that. What I meant is that the problem you allude to isn’t one. Only very few string theorists have were trained as mathematicians, and they think as physicists and not mathematicians. And they are smart enough to not confuse a mathematical proof with physical reality.

It is you who has a prejudice how poeple think and work, and this is sneaks in all the time. Like your “real science”…this expresses your doubts that string theory is real science. Or your “Same goes for your conveniently loose definition of a “result” below. Sorry, a result is a result! For example, that certain correlations functions in Yang-Mills theory and string theory coincide. This is a mathematical fact, and NOT a “conveniently loose definition”.

Same goes for your conveniently loose definition of a "result". In my view the only kind of result that matters is an experimental one:...

Well that’s your point of view. Fine. Many don’t share this point of view.

A conversation where we don't agree on the meanings of simple words can only descend into farce. Unfortunately, I assumed from the outset that these terms were so well established in science that we took them for granted.

Frankly I begin to doubt that you really know how science works.

I sought some clarification of why it is justified to claim that in BTSM theories we are discovering new physics rather than merely hypothesizing. People have made some interesting points but there has been no clear response to this question - I suspect that many string theorists actually disagree with it.

Again deriding: “merely hypothesizing”. Sorry, things are a bit more intricate than coffe table talk. Take for example, black holes. No one has yet seen one by naked eye (perhaps fortunately). Still they exist as solutions of Einsteins equations and people have been starting investigating them theoretically, even without initial experimantel evidence. You may call this “merely hypothesizing” but this is viewed by many as an important line of reasearch; and indeed, just because of the theoretical investigations which lead to understanding various properties of black holes, indirect evidence for their existence has been found, and I guess almost no serious astrophysicist would doubt their existence. If science would be done like you advocate it, namely starting from experimantal obervations, we wouldn’t be there where we are (as you need precise clues for what you look for, otherwise you may never notice it).

Same goes for the theory issue - some of you guys have been claiming string theory is a theory, even though many string theorists accept that it isn't. With inconsistency like this within the same discipline, we can only ever descend into conversational farce.

Because there is no absolute definition what a “theory” is. Every one may have a slightly different idea about this, that’s why you get different answers. And that’s also why this is an irrelevant point to discuss about. What matters are results, not names. It is you who brought up this irrelevant discussion, and now you complain.

 

[Fra]

You may call this “merely hypothesizing” but this is viewed by many as an important line of reasearch

I agree with that. Hypothesis generation - the precursor of any theory, is of course an important part of a scientific process. And the logic of hypothesis formation is extremely interesting. Something that is sometimes completely lost is simplistic analysis when one only focusys on the falsification/corroboration part, which is the easy part of the process.

I think one can simultaneously acknowledge the importance of thel logic of hypothesis generation (which relates to theory spaces) and still admitt that there is a difference between this and physics contents, although there may be some deeper ways in which they are related (but I don't think that's the main focus here).

/Fredrik

 

[Lt_Dax]

Frankly I begin to doubt that you really know how science works.

You smug and arrogant individual. People who resort to hubris usually do so when they feel threatened. (and it's not surprising that you didn't elaborate on the above point, because it was merely an ad hominem attack).

If I've learned one thing in this whole conversation, it's that it's other people who are apparently unclear about science works, not myself. You claim that the concept of a theory hasn't been well defined, which is ridiculous. If a "theory" can mean anything you like, or a "result" can mean anything you like, then you may as well be working on the perfect barm cake recipe.

This is why I will not choose to stay in academia: science is wonderful, but the people are ugly, petty and have muddled thinking, and there is too much of a tendency to "feather the nest". When people have decades-long careers to defend, they will change the meaning of words which have been well established through four centuries of history in order to squeeze in their pet project.

 

[Lt_Dax]

The google ads currently generated for my page about evolution being only a theory are somewhat amusing in the context. Hold that thought, I may come back to it in a few moments.

 

[MTd2]

This is why I will not choose to stay in academia: science is wonderful, but the people are ugly, petty and have muddled thinking, and there is too much of a tendency to "feather the nest".

That is not a reason for you not to stay in academia. In fact, you can make yourself quite comfortable given that the vast majority is the very attached to science as you and me (I agree 100% with you) see it. Besides, it is a wonderful source of models to high energy physics.

 

[Lt_Dax]

I actually enjoy models, we can learn from them, they're just not oracles of physical reality. Hold that thought for now...

 

[Lt_Dax]

About the silly claim that the term "theory" is ill defined. It's not. Its meaning was not established through dogma (that is agreed) - it was established through centuries of experience. This generally agreed definition is accepted because it works (pragmatism).

Bear in mind that if this wasn't true, we wouldn't be able to respond to creationists who claim that evolution is "only a theory".

(Note that dictionaries also report colloquial definitions of theory, like hunch, and mathematical theories - I ignore those).

Webster's dictionary:
From the primary entry:
theory: ""a scientific hypothesis that survives experimental testing becomes a scientific theory".

Webster's dictionary (secondary entry):
theory (science): "An explanation for some phenomenon that is based on observation, experimentation, and reasoning."

theory (geology) "...but in science, something is not called a theory until it has been confirmed over the course of many independent experiments. Theories are more certain than hypotheses, but less certain than laws."

Webster's wiktionary:
theory (sciences) "A coherent statement or set of statements that attempts to explain observed phenomena. There is now a well-developed theory of electrical charge."

Wikipedia:
Scientific theory: "A scientific theory is constructed to conform to available empirical data about such observations, and is put forth as a principle or body of principles for explaining a class of phenomena."

Wikipedia:
Same entry, pedagogical definition, USNAS: "The formal scientific definition of theory is quite different from the everyday meaning of the word. It refers to a comprehensive explanation of some aspect of nature that is supported by a vast body of evidence." and "One of the most useful properties of scientific theories is that they can be used to make predictions about natural events or phenomena that have not yet been observed."

(Wikipedia distinguishes an empirical theory, which is a scientific theory, from a formal theory, which means mathematical proof not scientific proof).

Oxford dictionary:
theory, noun: "a supposition or a system of ideas intended to explain something, especially one based on general principles independent of the thing to be explained: Darwin's theory of evolution".

TheFreeDictionary.com:
theory:"A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena."

Don't believe a string theorist who claims that there is no generally accepted view of the word theory. Evolutionary biologists, chemists, other physicists, geologists, etc., who are all professional scientists to be respected, and who all engaged in building scientific theories, all agree with the above definitions. You can't do careful work unless the basic principles of your subject are established.

 

[suprised]

Look, this discussion is completely irrelevant. It should be about the scientific content and not the name. While the many hundreds of people working on the subject of strings happily call this string theory, you are welcome to call it different. I don't mind if you call it "string $#$*#$", it won't make any difference. But I doubt you can convince the people in the field to call it "string $#$*#$".

Let me rethink what I said about obsession.

 

[MTd2]

I actually enjoy models, we can learn from them, they're just not oracles of physical reality. Hold that thought for now...

I was just giving you a reason not to give up academia.

 

[Lt_Dax]

Look, this discussion is completely irrelevant. It should be about the scientific content and not the name. While the many hundreds of people working on the subject of strings happily call this string theory, you are welcome to call it different. I don't mind if you call it "string $#$*#$", it won't make any difference. But I doubt you can convince the people in the field to call it "string $#$*#$".

Let me rethink what I said about obsession.

No, the discussion is not irrelevant, you just want it to be, because you find it uncomfortable.

You also make it sound like string theorists secretly know that it's just a model (or to use a cringeworthy term favoured by others, a "framework"), but I know this is not the case. If anything, the highest practitioners in the field (such as Green, Witten and others) talk in more grandiose terms than others. They not only think it is a theory, they think it is a theory of everything (!) and that the reason it is correct is because it is beautiful. Well beauty doesn't cut it. People who follow the Koran claim that its beauty is an indicator of truth , but obviously this argument is easily ignored.

I'll ignore the comment about obsession.

 

[Lt_Dax]

I was just giving you a reason not to give up academia.

I appreciate your support

 

[Lt_Dax]

It should be about the scientific content and not the name.

If any content is "scientific" then it can be, and should be, described in terms of meaningful words. Language, communication, really does matter. How can it not?

I've noticed that you are no longer challenging my point about what a theory is, now you've changed your argument to claiming that string theory is a theory, they just don't call it one by name - even though they actually do (huh? This is severely muddled up thinking). Both points are manifestly incorrect, and I have addressed both of these points in previous posts so there's no point in repeating what I've said before.

I think my original question about why we call progress in string theory discovery of new physics has been answered: string theorists don't even know. They contradict each other, and even an individual string theorist contradicts himself/herself!

 

[Lt_Dax]

Hypothesis generation - the precursor of any theory, is of course an important part of a scientific process. And the logic of hypothesis formation is extremely interesting. Something that is sometimes completely lost is simplistic analysis when one only focusys on the falsification/corroboration part, which is the easy part of the process.

I just want to pick up on this if I may. I never said that hypothesizing is not part of science. I said that engaging in hypothesizing alone, and claiming it is progress, or even discovery, as your hypothesis becomes more and more complex, is meaningless. Hypothesizing and testing the hypothesis to see if it can be accepted into a theory go hand in hand, like bangers and mash.

This is why it is absurd when people say that we don't understand string theory yet, using language as though we're actually slowly unveiling physical reality. You don't understand your own hypothesis which you seek to test? Ridiculous! The whole point of generating a hypothesis is that it is well understood so it can be tested. It certainly should not morph into some sort of pseudotheoretical collection of hypotheses (I'm sorry, a "framework" ). The claim made by Witten that string theory is 21st century physics discovered in the 20th century shows you the hubristic mentality of the people involved, in my opinion.

 

[negru]

I'm surprised no one brought up the "but membranes aren't 1d why do people still call it string theory" discussion.

Dax, honestly, no one cares and will never care what exactly is a "theory" and if string theory qualifies as one. People only care about results. If you think the name of string theory should be changed...I don't know, try writing to your congressman.

And for the love of god (pun intended) do stop already with creationist vs evolutionist argument. It's childish, getting old, and you're misusing it.

 

[Lt_Dax]

Dax, honestly, no one cares and will never care what exactly is a "theory" and if string theory qualifies as one.

Correction, some string theorists don't care. Many thinking people do care. I'm not alone. You have a nerve accusing me of childishness, when you try to dismiss an entire thread with "nobody cares"! That's school playground language!

People only care about results.

And what makes something a "result"? Is something a result because it gets accepted for publication? This viewpoint stinks. Just because an idea is published, doesn't mean it represents physical reality. Maybe it's true that people only care about the number of publications and citations they get. Publish or perish?

And for the love of god (pun intended) do stop already with creationist vs evolutionist argument. It's childish, getting old, and you're misusing it.

In what way am I misusing it (care to explain)? It's highly relevant. There isn't one definition of science in evolutionary biology, and another in physics. The methods of science are universal. We only divide science into separate subjects to make it easier to understand. Nature doesn't have clean dividing lines.

You can't conveniently dismiss the discussion about evolution/creation just because it comes from a different subject. It illustrates the point perfectly about what a theory is. Need I repeat that it means something much more precise than just an idea? This really matters, whether you think it does or not.

I repeat that it's quite amusing of you to accuse me of being childish, when your concluding argument seems to be merely "it doesn't matter, nobody cares, stop whining". Is that the best you can do?

 

[Haelfix]

I just want to pick up on this if I may. I never said that hypothesizing is not part of science. I said that engaging in hypothesizing alone, and claiming it is progress, or even discovery, as your hypothesis becomes more and more complex, is meaningless.

Suffice it to say, I think you'll find that most proffessionals will disagree with this statement. I certainly do, and I suspect most others will as well.

Sometimes progress can be made in pure theory, without the need for experiment. Its particularly true that you can falsify most ideas, long before you ever test them.

When a statement is inconsistent with logic, then that's all there is too it. I don't need experiment to tell me that the collision between two gravitons does not output pink elephants.

The reason so many people believe in string theory, is that there aren't many (arguably any) viable alternatives and you are very much bootstrapped into this way of thinking through a rather tight network of highly plausible inferences (for instance, the existence of black holes as being 'real').

In some ways, it is the theory with the minimal set of assumptions necessary that also simultaneously explains the bewildering array of modern physics that is observed.

This is not supposed to be *obvious* to a layman! They see complicated mathematics, extra dimensions and a bunch of structure that looks many steps removed from the laboratory and immediately complain. Well, until one actually does the math and see's that the arguments for each step are actually pretty tame and natural, be sure that the person will stay hostile to the idea.

 

[Lt_Dax]

Suffice it to say, I think you'll find that most proffessionals will disagree with this statement. I certainly do, and I suspect most others will as well.

Hypothesizing is not discovery, no matter how sound or simple the step of logic used to achieve your hypothesis. It still needs to be tested to become a theory - a description of reality. A "professional" is not correct just because they have authority.

Sometimes progress can be made in pure theory, without the need for experiment.

The word progress could mean anything here. What do you mean? Lots of publications? By the way, the concept of "pure theory" is a contradiction in terms. A theory is linked to experiment by definition.

Its particularly true that you can falsify most ideas, long before you ever test them.

You can't falsify a hypothesis without testing it, by definition. However, if something is logically flawed, then it never gets called up for testing in the first place. It's not even a hypothesis, it's trash, surely.

The reason so many people believe in string theory, is that there aren't many (arguably any) viable alternatives

Alternatives in doing what? You're going to have to be more clear than this.

In some ways, it is the theory with the minimal set of assumptions necessary that also simultaneously explains the bewildering array of modern physics that is observed.

Most of observed modern physics is explained with the standard model, and the rest of the unsolved observations are not explained by string theory, otherwise we wouldn't even be having this conversation. So what are you talking about?

This is not supposed to be *obvious* to a layman! They see complicated mathematics, extra dimensions and a bunch of structure that looks many steps removed from the laboratory and immediately complain. Well, until one actually does the math and see's that the arguments for each step are actually pretty tame and natural, be sure that the person will stay hostile to the idea.

Well, I'm not a layman (although I'm not a string theorist), so I don't know how this applies in this case. I resent the implication that I'm too stupid to see how wonderful and beautiful string theory is. This sounds a lot like when religious people say that a person just doesn't have god's spirit and therefore couldn't possibly appreciate the beauty and truth of said belief. It's a bogus argument and a fallacy.

 

[Haelfix]

When I say progress, I mean discovery about how the real world works (tm). When I say alternatives, I mean alternatives about the nature of the Planckian world.

"Most of observed modern physics is explained with the standard model, and the rest of the unsolved observations are not explained by string theory, otherwise we wouldn't even be having this conversation"

Umm, String theory contains the standard model as a low energy limit, and I don't know which 'unsolved observations' you are referring too? B/c in principle, it does contain the explanation! That's what it means to be a possible theory of everything! If you can find an observation about the real world that string theory does not contain, then by definition you have falsified the theory.

"You can't falsify a hypothesis without testing it, by definition. However, if something is logically flawed, then it never gets called up for testing in the first place. It's not even a hypothesis, it's trash, surely."

Now you are playing with semantics and besides, this is wrong! You *can* falsify theories without testing them. Most of the time a Gedanken is all that is required.

For instance, I don't need to test the nature and predictions of creationism. I know its wrong, b/c it is logically inconsistent and absurd and clashes with many known phenomenon that have been tested.

 

[Lt_Dax]

When I say progress, I mean discovery about how the real world works

To find out how the real world works you have to interrogate nature. There is simply no alternative - even if your ideas are wonderful, they have to be tested.

When I say alternatives, I mean alternatives about the nature of the Planckian world.

We bring up alternatives as and when they are needed. Special relativity was proposed because there were unexplainable experimental observations. We do currently have unexplainable experimental observations, but string theory doesn't explain them, it purports to do something different (I assure you that if string theory explained these things we don't understand, it would be all over the world's media).

Umm, String theory contains the standard model as a low energy limit, and I don't know which 'unsolved observations' you are referring too?

String theory contains the standard model, so what? Why reinvent the wheel? Some people have suggested that ST is merely a calculational device for amplitudes. In that case then, it doesn't even qualify as a hypothesis, it's just a tool. Some unsolved observations: Dark energy/matter, the arrow of time, the origin of mass, explaining confinement, neutrinos etc. etc. Has string theory had explained these things? If it had we'd have heard about it.

Now you are playing with semantics and besides, this is wrong! You *can* falsify theories without testing them. Most of the time a Gedanken is all that is required.

No, my semantics (meaning) are clear. I have been crystal clear about what I mean by "theory", "result", "hypothesis" - on the other hand, you contradict yourself within the same sentence even! You've already changed from "hypothesis" to "theory" in your response! So who's playing games with meaning? Not only that, but you merely made an assertion (that you can falsify a theory without experiment) without explanation. And I don't know what a Gedanken is...

For instance, I don't need to test the nature and predictions of creationism. I know its wrong, b/c it is logically inconsistent and absurd and clashes with many known phenomenon that have been tested.

Creationism does not qualify as a hypothesis because the existence of god, for example, can neither be proved or disproved and is therefore not a scientific question. This proves my point, not yours.

 

[marcus]

... String theory contains the standard model as a low energy limit, ...

Haelfix I don't think it is true that any version of SST contains the SM and its 20-some mass etc parameters (correct me if I'm wrong) but I would be interested if you would give me an arxiv reference to some paper which documents a version of SST which comes closest to that desirable goal. If you have a favorite amonst the many alternatives, I'd be delighted to read about it.

...String theory contains the standard model, so what? Why reinvent the wheel?...

But Lieutenant, where did you hear that SST contains the standard model of particle physics? I have always heard the contrary, from sources I consider reliable. They have made great efforts, trying various ways to roll up and stabilize the extra dimensions, in the attempt to get standard particle physics with its various particle masses, coupling constants and so forth. I think it would be great news if those efforts had succeeded!

Let's see what journal article preprint (online arxiv source) Haelfix offers us.

 

[Lt_Dax]

But Lieutenant, where did you hear that SST contains the standard model of particle physics? I have always heard the contrary, from sources I consider reliable.

I was just taking his word for it really - although since I've not seen any publication which shows this myself, I share your skepticism.

 

[Kevin_Axion]

Lt_Dax do you think you can tell me what exactly everyone is arguing about, is it the merits and faults of String Theory? This has become very unclear to me.

 

[Lt_Dax]

Kevin_Axion, my primary point of contention has been about why it is justified to claim physics discovery and what it means to discover anything in science - my viewpoint has somewhat hardened from asking a question to making an assertion - mainly because it has become clear that many practicing string theorists have never sat down to think about what all these words we chuck around actually mean (I no longer feel like an inexperienced student asking a question - I overestimated the wisdom of the people I was asking.)

But as I've said in the distant past, this is not about questioning the interesting nature of string theory or its usefulness in model building - but I've never been able to have a decent conversation about this because some string theorists have been using words like theory, hypothesis, model, framework, result, progress interchangeably. Others are dismissive and say it doesn't even matter and that I should stop "complaining". So I agree with you that it is confusing, but this is not your fault or mine.

 

[samalkhaiat]

If this was 1954, this thread would have been about Yang-Mill’s theory! Back then, some people (mostly non-professionals) called it “fancy mathematics”, others (including some professionals) said: “it is worthless” because it disagreed with the observed short-range nuclear force. But, a class of good physicists saw Yang-Mill’s as a “beautiful and logical next step in theoretical physics”.
It took those good physicists 20 years of hard work to realize that nature is indeed fundamentally Yang-Mill’s. They, deservedly, got Nobel prizes and we (thanks to them and to Yang and Mill) got the electro-weak and QCD.
So, people work on string theory because they see it as “the one and only logical next step in theoretical physics". Those who can't see this, well they just can't!

Regards

sam

 

[negru]

Well maybe this is the thing you're misunderstanding. String theory is both a framework and a model - it's just that awesome.

How to reconcile these things? Work in progress.

What are you arguing about? Results in any of these two categories?

-As a framework, it has already proven useful in a many areas, like scattering amplitudes. Anyone working on scattering amplitudes is just shooting himself in the foot by ignoring string theory.

-As a model, technically we're just missing a selection principle to choose from the landscape. Hardly an obvious dead-end or utter failure.


Progress in both of these areas is happening everyday. Sometimes small steps, sometimes larger ones. Why is everyone so anxious?

 

[Lt_Dax]

@samalkhaiat @negru

So it comes back to this argument - I'm just too dumb, too naive to see the awesome, wonderful, beautiful truth. Who knows, maybe it's true, and I just can't see what these towering genuises can see.

Of course, there's nothing more suspicous than a self-declared genius or a self-declared revolution. That is reason enough to remain skeptical.

 

[Haelfix]

Again it depends what you mean by the 'standard model'. If you mean the group structure, generations and form of the particles and interactions then yes, string theory has had this for a long time. If however you want calculations of the exact mass of the Higgs down to 5 decimal places, sorry but the calculation is prohibitively difficult in many vacua. The best you can do is proof of concept.

http://arxiv.org/abs/hep-th/0512177 for an example of a paper with realistic vacua that also contains the SM. There are literally hundreds of other ones, that appear weekly on Hep-ph.

"I don't know what a Gedanken is..."

Oye! Look, I'm not going to continue this anymore. I don't feel like getting lectured about the scientific method... Seriously!

 

[negru]

There's a difference between being skeptical and what you're doing in this thread. Personally, I'm also skeptical of the traditional path to unification, I'm more of a gauge/string duality fan. But I just leave everyone do their own thing, how's it any of my business what others work on? Including creationists. If you like evolution so much, why are you so stressed out? Natural selection will make sure wrong theories eventually die out, no?

 

[Lt_Dax]

I don't feel like getting lectured about the scientific method... Seriously!

Well then learn what it is. Nobody will lecture you about it then.