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Science

Why String Theory Is Not Science (forbes.com) 288

StartsWithABang writes: Earlier this month, a conference was held devoted to the question of whether untestable scientific ideas like string theory and the multiverse are actually science or not. While many opinions were stated and no one changed their mind, the answer is apparent: unless you're willing to change the definition of science to include "this thing that isn't science," then no, string theory is not science. It's a theory in the sense of a mathematical theory — like set theory, group theory or number theory — but it isn't yet a scientific theory. Of course, it could become science, but that would require that it actually do the things a scientific theory does: make testable predictions that can be validated or falsified.
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Why String Theory Is Not Science

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  • by Roger W Moore ( 538166 ) on Friday December 25, 2015 @01:33PM (#51182591) Journal
    The condition for science is that it has to be testable in principle, NOT that it has to be testable within the limits of current technology. When Higgs came up with his theory there was no accelerator capable of testing it (although we did not know that at the time). So would that make the Higgs mechanism non-science until the 21st century when we built the LHC? Clearly not. So, unless String theory is completely untestable in principle, regardless of potential future technological advances, it is science albeit science which is currently impossible to test with current technology.
    • by hey! ( 33014 ) on Friday December 25, 2015 @01:55PM (#51182663) Homepage Journal

      The classic example used by logical positivists in the early 20th century was any conjecture about the far side of the Moon. Until we developed spacecraft any statement about the half of the Moon we can't see would have been untestable in practical terms, but it would have been testable in principle.

    • So, unless String theory is completely untestable in principle, regardless of potential future technological advances, it is science albeit science which is currently impossible to test with current technology.

      That is what the article claims to be. It mentions that if we could test for Super-Symmetry it would support String Theory, but that String Theory is not the only theory that predicts it. The author claims that there is no test that can be done that would prove String Theory true as opposed to other theories.

      • by Roger W Moore ( 538166 ) on Friday December 25, 2015 @03:07PM (#51182945) Journal

        The author claims that there is no test that can be done that would prove String Theory true as opposed to other theories.

        Unfortunately the author has proven many times that he does not understand particle physics in previous posts. The problem with String Theory is that there are far too many possible theories to consider (last count I heard it was around 10^500) to make detailed, concrete predictions. The second that we get an experimental signature for something like String Theory that number would collapse and theorists would be able to start studying the detailed predictions of a vastly smaller number of models. This would undoubtedly lead to some clever theorist coming up with signatures unique to String Theory which other, competing models would not have.

        If you can't come up with ANY difference it would mean that the theories must be mathematically equivalent for all situations which are possible. We have had this happen in physics before. Matrix mechanics and wave mechanics are both different ways of doing the same Quantum Mechanics. Nobody worries about which is the "right" way because both make mathematically equivalent predictions.

        • The second that we get an experimental signature for something like String Theory

          What sort of thing would you do to get an experimental signature for String Theory?

      • by tnk1 ( 899206 )

        There are predictions out there that will need to be made. If string theory predicts them, then it is (up to that point) accurate. If it doesn't do a better job than some other theory or model, then it's still accurate (to that point) but then a decision needs to be made about what is the better model or theory to move forward with.

        In the end, most competing theories are either going to be wrong or exposed as a more complicated way of saying the same thing. In practical terms, if we really believe that w

    • To put it briefly [xkcd.com].......
    • by mbone ( 558574 ) on Friday December 25, 2015 @03:13PM (#51182975)

      The condition for science is that it has to be testable in principle, NOT that it has to be testable within the limits of current technology. When Higgs came up with his theory there was no accelerator capable of testing it (although we did not know that at the time). So would that make the Higgs mechanism non-science until the 21st century when we built the LHC? Clearly not. So, unless String theory is completely untestable in principle, regardless of potential future technological advances, it is science albeit science which is currently impossible to test with current technology.

      String theory is arguably not science not because it makes predictions we cannot test, but because it basically makes no predictions at all. Originally, when people realized the importance of 10-dimensional manifolds (i.e., of theories with 6 compact dimensions), there was a lot of excitement as people thought (and confidently said) that there would be one and only one suitable such manifold, which would have led to concrete (if maybe hard to test) predictions. But, now, there is a huge number (order 10^500) of such manifolds known, each basically allowing for a separate theory, and we have no idea which could be the right one.

      Also, there is the pesky fact that predictions have been made about the foundations of string theory (that, for example, the LHC would detect the supersymmetric partners of existing particles), and they have not been born out by experiment,

      Having said that, my personal feeling is that string theory is science, but science that is unlikely to be fruitful. Eventually, unless this changes, something else will come along, and it will cease to be the center of attention for theoretical physics.

      • by lgw ( 121541 )

        As I understand it, String Theory has one fundamental (and very odd) premise: that all particle masses are integer multiples of the Planck mass, with all known particles having a rest mass of 0, plus a bit of rounding error (OK, it all sounds fishy to me, so maybe I don't quite have that right). Anyhow, the discovery of particles with about 1 Planck Mass (obviously not point particles) would be an experimental triumph. And who knows what dark matter is - maybe there's a surprise waiting.

        But other than tha

    • The condition for science is that it has to be testable in principle, NOT that it has to be testable within the limits of current technology. When Higgs came up with his theory there was no accelerator capable of testing it (although we did not know that at the time). So would that make the Higgs mechanism non-science until the 21st century when we built the LHC? Clearly not.

      There's a difference: it was possible long before the LHC to test the Higgs theory for consistency. The Higgs made predictions about how other particles (not the Higgs) would interact with each other. Those could be tested in accelerators which were not energetic enough to produces the Higgs directly.

      String theory? Not so much.

    • In that case wouldn't it be a hypothesis? It's untested and, beyond filling some gaps in quantum theory and relativity, it hasn't been mathematically proven.

      So it's a hypothesis, right?

    • By that logic:

      * The Big Bang Theory is not Science,
      * hell, most of Astrophysics is not science either

      Science is nothing more then Applied Philosophy.

      What makes the Philosophy (of Science) interesting is in the trying to Apply it. If we tossed out every scientific philosophy simply because we didn't have a way to (yet) test it, Science would remain an incredible narrow domain. Science is supposed to be about Truth. Once we start artificially limiting how the Truth is arrived at you have a cult / dogma.

      Bel

  • a theoretical physics model?

    • by nashv ( 1479253 ) on Friday December 25, 2015 @01:45PM (#51182629) Homepage

      Exactly. It is a model. It might even be a useful model with some explanatory power. But the same can be said of many belief systems. The only difference is that the other belief systems have been shown to be inaccurate by showing their contradictions with reality. With string theory, we are not aware of any specific such contradiction yet.

      I don't think we should have any problems with models, as long we understand very clearly that they are only models. Like Newton's laws - they are strictly inaccurate but as approximate models of reality that are valid under some limited set of conditions, they remain useful.

      • by losfromla ( 1294594 ) on Friday December 25, 2015 @03:05PM (#51182941)

        There are too many floaty numbers inserted and whenever the numbers don't work more floaty numbers and dimensions are added in to make the "theory" work. Books written about this "Not even Wrong", "The Trouble with Physics". There may be others, those are just two I am familiar with.

        http://www.amazon.com/Not-Even... [amazon.com]
        http://www.amazon.com/Trouble-... [amazon.com]

        • by nashv ( 1479253 )

          So you have a problem with the mathematical hypothesizing that is involved in string theory? Hypothesis generation is an integral part of science.

          The fact that the degree of adjustment required in string theory is unsatisfactory to you is perhaps indicative of the fact that string theory is a poor model of reality. On the other hand, it could indicate that reality is actually rather messy.

          It is true that simplicity and elegance often seems like characteristics of correct models of reality. However, "messine

          • Hypothetical, like any fantasy book, yes.
            I have no problem with mathematical hypotheses, I am sure they are quite fun for those who play with them. The only issue I have is when any fancy thoughts like pretending they somehow are linked to reality come up. From what I gather, very good math progress has been made when attempting string theory work. Sort of like Disaster Area Tax returns, they advance the state of the art.

        • The same can certainly be said of the standard model as well.
    • Science is all models, so if it is a theoretical physics model then it is science.

  • It's just IRONIC science, per John Horgan. [amazon.com]

    RS

  • First, there is no string theory. There are a bunch of theories we call string theory. There are a bunch of theories that we call string theory, abut no basic priciples that are clearly laid out yet.

    Second, even if we had a specific theory, we still do not know how to make calculations.

    Third, general relativity was in the same situation. For a long time all it predicted was Mercury's perihelion precession and that could be done with alternate theories of gravitation or even extra planets. It wasn't until

    • by chthon ( 580889 )
      Is string theory really a theory? I would submit that after more than thirty years it is still a hypothesis.
      • Oxford Dictionary:

        hy.poth.e.sis
        a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation:

        What is the limited evidence?
  • There are a lot of pseudo scientists out there and it is not helped by masses of typically arrogant people that think they know what science is in the first place.

    People confuse POLITICS with science. Bring up something about science and they'll say stupid things like "well X number of people agree with me" which isn't science. That is politics. Or you'll see something along the lines of "look at my nifty idea... all the numbers add up"... great... still not science... not unless you want to include Dungeon

    • by vux984 ( 928602 ) on Friday December 25, 2015 @02:43PM (#51182835)

      I think cargo cults are pretty science-ish.

      The observed a correlation between airports and cargo planes arriving.

      The formed a hypothesis that constructing something that looks like an airport and control tower would bring the cargo airplanes.

      They tested the hypothesis, by building the airport etc. It didn't work.

      They (correctly) knew that something made the cargo planes come; so they tried to improve their emulation of the airport operations etc.

      Sure if was fundamentally wrong. But it WAS the scientific method in action. Observation, hypothesis, experiment...repeat.

      Its no different than heliocentric astronomy. We kept trying more complicated and elaborate constructions to predict the planetary motions, but it just kept failing because it was wrong.

      • by chthon ( 580889 )
        I think that epicycles worked for a large part. But what happened is that they were an incomplete model, that was always more and more incorrect due to more precise observations. It would be like trying to compute a sine wave by simple algebraic functions. It works up to a certain precision, but then it breaks down.
      • Except it doesn't work.

        Watch the video again. Cargo cult science "looks" like science... only it doesn't work.

        You can't get around that. This is what ultimately stopped sophists from dominating western philosophy. Stoic Empiricism.

        It. Does. Not. Work.

        You can spin your theories till your head spins off... it won't work if you don't do it properly. And if you don't do it properly then it isn't science.

        And because I'm sure you're going to presume to nitpick me here and thus miss the entire point... let me be v

        • by vux984 ( 928602 )

          They had "faith"... and that faith made it not science because when the evidence came back that the hypothesis was bunk... they just doubled down.

          What evidence? Failure to succeed is not evidence that the hypothesis is bunk; especially if there is room in the hypothesis for additional refinement.

          Science does this all the time. Consider the 'planet vulcan', which many (if not most) scientists believed existed, and searched for. And the repeated failures to find it were attributed to calculation errors, inadequate instruments, etc... but they kept trying. Building better instruments, refining the calculations... until General Relativeity explained the

  • by UpnAtom ( 551727 ) on Friday December 25, 2015 @02:51PM (#51182887) Homepage

    David Deutsch argues that it is core:
    https://www.ted.com/talks/davi... [ted.com]

    Also, string theory is surely as testable as quantum mechanics. It's just currently impossible to say which is more valid.

  • by radarskiy ( 2874255 ) on Friday December 25, 2015 @02:57PM (#51182909)

    They start with the premise that string theory is untestable, and come to the conclusion that it is untestable.

  • Tiny vibrating strings? That explains everything! But why not tiny vibrating llamas? I bet the math would still work out, plus that would make the theory somewhat interesting.
    • Tiny vibrating strings? That explains everything! But why not tiny vibrating llamas? I bet the math would still work out, plus that would make the theory somewhat interesting.

      Step 1: Assume string shaped llamas.

  • by Kjella ( 173770 ) on Friday December 25, 2015 @03:35PM (#51183063) Homepage

    For example, the theory that all matter is made up of small, indivisible bits (atomos) is unscientific. Whenever you find a new smallest building block (atom) there's a chance you'll find they're built by even smaller blocks (a core of protons and neutrons surrounded by electrons) and that protons again are made from even smaller particles (quarks). And maybe the quarks are built from superstrings. And maybe the superstrings are build from something we don't even have a name for yet. That doesn't make them bad ideas to guide scientific research and design experiments. Just like causality is a rabbit hole with no end, even if we could explain the whole formation of the universe back to the Big Bang we'd always be looking for what caused the Big Bang. And what caused that which caused the Big Bang. Scientific exploration is an educated guesswork, you take some observations and try to find a system or pattern or formula and if the results don't contradict reality, great. It's obviously even better if you can predict something new, but if I find that E = mc^2 and show a few reproducible examples it's up to the rest of the scientific community to find a contradiction where E != mc^2. I feel it's a bit like that with superstring theory, if we got multiple theories that both come to the same results then either they're different formulations of the same model or there will be distinct differences that are at least hypothetically testable.

  • It worked great when we really did not understand anything about the Universe. But now when quite a lot is already known, there is a hell of a to less you can predict. Like all the current accepted theories, they predicted things, but now their predictions are just known facts, so if someone come up with the theory of tectonic plates today, it could never be a science, as all predictions you can make with the theory are already known facts. It just seems wrong, that if a prediction is not made in time, then

  • by doug141 ( 863552 ) on Friday December 25, 2015 @04:03PM (#51183221)

    If you find yourself talking to a person who dismisses talk of multiverses or string theory as no better than talk of the supernatural, just ask them what a person would see while falling into a black hole. They will proceed to tell you their version. Then ask if someone outside the hole can ever verify anything they just said. They will say no, communication won't work from inside an event horizon to the outside. Then ask, if everything they said is all based on conjecture and extrapolating known laws, and can't be experimentally verified, why do they feel it merits discussion?

    • And they respond "Because you asked me to expound upon my imagination." Glad to see you believe string theory and multi-universe don't merit any more discussion than someone's imaginings though.
  • I think we have to be careful here, as the atom was only a theory for over a hundred of years.

    There is also an issue that classical physicists would not want to believe that their theory fits into anything larger, as Newtonian physicists likely did not want to believe in relativistic physics, as religious types did not want to believe....

  • It is currently not testable. That means that this hypothesis remains open. The same is true with the Multiverse.

    The Higgs Boson wasn't testable untily recently. This did not mean the theoretical hypothesis was invalid.

    Personally, I believe that the Universe will explode at the speed of light if anybody actually figures out what its purpose is, and that when it happens it will be instantly replaced with something even more bizarre and inexplicable. There are others that believe that this in fact has alr

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