Shelly Glashow (electroweak fame) asked a socratic question: " is string theory a science or a philosophy, I put it to you?"

I see his point. Strings seem to have been successful in producing a string graviton and hope for a quantum theory of gravity as well as details on black holes. But they fail to explain the big bang and do not have any experimental confirmations: not yet. I did see a team at Fermilab looking for a graviton leaving our brane and escaping to another but they didn't see it yet.

Dennis Overbye of the NY Times in a 12-7-04 article asks: "based on what you've read, how much effort do you think scientists should continue to make in pursuing string theory? Defend your opinion." Brian Greene recently piped up at a string conference in response to someone who said it would be great to find out string theory was right: " wouldn't it be great either way?"

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'Just be a good team player in life', Andrew Evans

I'd say it's neither a theory or a philosophy. It's more like a line of conjecture that has produced a number of hypotheses in the form of different specific formulations of string theory.

Too much math, not enough word-salad to be philosophy.

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The bar has been lowered for the promotion of ATM ideas; the bar for the acceptance of ATM ideas must remain high.

For the time being, string theory is just a mathematical construct. But who knows, if the LHC detects supersymmetry particles, which are predicted by string theory, it would be a key confirmation.

I watched an interview of Brian Greene by a BAUT member recently. What an awesome guy. He was said something like 'I don't believe in string theory. No one should! Not until it is confirmed with consistent experimentation'. What a model scientist.

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It think should be called 'String Hypothesis', since there´s a viable math to support it, but lacks any remote experimental evidence.

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While we're at it, until it was proven in the 1990s Fermat's Last Theorem wasn't really a theorem at all.

To win a tournament, it is necessary, but not sufficient, to win through the early rounds.

The fact is that supersymmetry is necessary, but not sufficient, for string theory. Supersymmetry can be true without strings. A supersymmetric standard model has been constructed. So discovering supersymmetry does not provide any direct evidence for string theory. But if LHC results made it possible somehow to exclude supersymmetry, strings would be out of the tournament.

Agreed. So far, it's a purely theoretical construct, akin to mathematics -- although the people who work in it probably prefer to call it "theoretical physics", and not without reason.

It isn't testable so far, but there is a possibility that a way to test it against other alternatives will be found in the future.

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Another possibility might lie in the detection of cosmic strings.

http://www.physorg.com/news120823753.html

Ditto.

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I are Learnding.

String theory is a mathematical construct that does need some lab confirmation before it can be called science. Yet lab confirmations are based upon falsification attempts and recognizing something as being made up of sub-components to describe its presence. We recognize cars because we can describe the sub-components. Sometimes we can infer the existence of a car's presence by the tracks it left behind in the snow. Many particles are found that way in particle accelerators.

But strings, even if they are real and the string theorists are right, cannot be made out of anything or they wouldn't be the most fundamental particles in the universe. So we can only infer their existence. The sizes of the spots in the CMB are supposed to contain mathematical signatures of string theory according to Jim Gates. I got the impression from taking his video course that if the lightest supersymmetric particle (the LSP) turns out to be a squark, then string theory won't be able to be falsified for another 300+ years and that should be its cutoff line for funding.

The following was the closest to putting string theory in the lab 2 years ago:

http://www.eurekalert.org/pub_releas...-ppc050207.php

I have been waiting for a follow-up and there hasn't been one. With the behavior of quarks at room temperatures being amply predicted, one would think they should be able to describe quark behavior in a flower as the sun rises or a virus enters a cell.

Well, there was that "mini-black hole precursor" thing they found at RHIC that was totally unexpected. They're still not sure what they conjured up; but it would seem to indicate that miniblack holes can be produced in high energy colliders at much lower energies than the standard model would suggest. So if the CERN LHC can turn itself into a "black hole factory" as the famous Steve Giddings has predicted, that would be an important confirmation of string theory, lending strings the same metaphysical status as electons, and other such entities that are too small to be directly experienced by humans.

Warren. The energy of the LHC, when it gets up and running, still does not exceed the energy of the highest energy cosmic rays. Even while they were running calibration studies on the LHC, they used the slow but steady trickle of cosmic rays through it to test their selection algorithms...screening for constant momentum, conservation of mass/energy, charge, baryon number/ strangeness,lepton number, etc... If supersymmetry is to have some validity, it ought also to show up in the cosmic rays. 17 particles, and 17 supersymmetric anti-particles, over twenty years. Nada. No cosmic ray has ever produced one. Nothing at Fermilab. Nothing at CERN. or KEK...or Serphukov...or DESY, or CEBAF....or SLAC...or BATES. NADA.Not a single one has been verified.(which is why Brian Greene took the conservative approach he did in the interview). I don't begrudge people taking different paths of investigation, you learn as much from what doesn't work as you do from what does, but it's been a long torturous route for people who signed on early for supersymmetry and spent years devising tests for it. It has the feel of the Bermuda Triangle, Nessie, Ogopogo, Bigfoot, greys, Bob Lazar, area 51, ....all wrapped up together. For a high tech field, that's not a good feeling.
We might see new physics at the LHC. We might see something strange at an UHEC detector, or Ice Cube retrofitted to gather acoustic signatures, too....or we might be at the end of the road. If a 100 solar mass star undergoes core collapse, and doesn't yield a black hole....and we have at least one 40 solar mass precursor that did just that(pulsar not black hole), then the high temperature physics there may be indicative of a theoretical quirk intrinsically prevents that from happening. That might be something the LHC will see.....but it should also be showing up in careful cosmic ray studies.
When T.D.K. Lee and C.N.Yang found parity conservation failure in the fifties, it showed up in every run of every experiment that had ever been run..it wasn't discovered because...........nobody had ever looked. pete

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A third rate theory forbids.
A second rate theory explains after the fact.
A first rate theory predicts.
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pete,

I am not sure I follow your line of reasoning. Are you suggesting that we can measure supersymmetric particle signatures from cosmic rays? The half-lives are too short and they all decay into the LSP, string theorists answer to DM, something that does not move at relativistic speeds and only interacts gravitationally from what little I know.

blueshift. A number of people have suggested, through the years, as each incremental advance in energy was made at the various accelerators/colliders, that we could be finding sparticles....the signature of supersymmetric reality, or anti-sparticles, their supersymmetric partners. There are as I recall 17 of each. That's 34 to look for. As we speak, none have been found. No collider we build will ever have the energy of the ultrahigh energy cosmic ray flux....~10²⁰ev, so we should at least check there, even though they are sporadic and the flux is low. Detectors can measure decays in as short as 10^-23 seconds. That's pretty quick. If I had a cleanup hitter for the Red Sox who was 0 for 34 for twenty straight years, or with a few trillion at bats per second for twenty straight years... I think Red Sox Nation would lynch the manager. Talk about jaded optimism. pete.

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A third rate theory forbids.
A second rate theory explains after the fact.
A first rate theory predicts.
A. Lomonosov

pete, I would think that you are right if string theory is false. If it is not false then all 17 (if that is the correct number) decay into dark matter and that may occur at a shorter interval than 10^-23 seconds. If extra dimensions are there, then the number of charges and charge carriers must be greater to hold things like hypercubes together, if they exist.
Secondly, the topology here might be too weak to allow a sparticles' half-life to last long enough that just might need the extra directions of motion to decay at a detectable rate.

That last point gives reason to your argument. In that case it is a waste of time.