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String Theory Tested, Fails Black Hole Predictions 307

Posted by CmdrTaco
from the you-fail-it dept.
eldavojohn writes "Back in 2006 there was a lot of talk of testing String Theory. Well, today CERN has released a statement for the Compact Muon Solenoid Experiment. The short of it is simply that as far as they could tell, 'No experimental evidence for microscopic black holes has been found.' The long statement indicates that since the highly precise CMS detector found no spray of sub-atomic particles of normal matter while LHC smashed particles together, the hypothesis by String Theory that micro black holes would be formed and quickly evaporated in this experiment was incorrect. These tests have given the team confidence to say that they can exclude a 'variety of theoretical models' for the cases of black holes with a mass of 3.5-4.5 TeV (1012 electron volts). Not Even Wrong points us to the arxiv prepublication for those of you well versed in Greek. While you may not be able to run around claiming that String Theory is dead and disproved, evidently there are some adjustments that need to be made."
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String Theory Tested, Fails Black Hole Predictions

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  • Simple (Score:5, Funny)

    by ledow (319597) on Thursday December 16, 2010 @11:25AM (#34573850) Homepage

    Simple. The Creator obviously didn't NULL-terminate. Hence his strings have no black hole at the end.

  • by Pojut (1027544) on Thursday December 16, 2010 @11:30AM (#34573926) Homepage

    One day, Bob the Scientist was puffing on some buddha. He smoked and smoked, and smoked some more. Suddenly, Bob the scientist looked down: the lines between the tiles on the floor started to wiggle this way and that, giving the tiles the impression that they were vibrating. Bob the Scientist blinked his eyes twice, only to see the lines still wiggling, enticing them with their random, chaotic dance.

    "That's it!" Bob shouted. "That's the answer, man!"

    Bob the Scientist went and grabbed Bill the Scientist. He pointed at the floor, saying over and over again "The lines, man! Look at the lines! Wooooooaaaaaahhhhh."

    Bill the Scientist sniffed, and said to Bob "Bob...have you been smoking that crazy ganja again?"

    "Yes, but so what? Duuuuude...the liinnnes...their taaaalking to meeeee..."

    "Give me some of that shit." Bill the Scientist took a big drag, looked down at the floor, and they both stared. "Woooooaaaaaaah...we better write this down, so we don't forget!"

    And thus, string theory was born.

    • You'd be funny if you didn't confuse acid for pot. Just b/c you're a geek doesn't mean you have to be a square.

      • by Pojut (1027544) on Thursday December 16, 2010 @11:48AM (#34574230) Homepage

        The whole "vibrating line" thing is based off an optical illusion that affects even sober people, which pot can exacerbate. If it was LSD, the tiles would have been floating slightly above the ground and shifting colors, rather than something as simple as stationary lines showing trail-like vibrations.

        I've been called many things, but never a square :p

      • by mcgrew (92797) *

        If it was acid he'd have a REAL hard time writing it down.

      • by zero0ne (1309517)

        Damnit, I wish I hadn't posted so I could rate you informative :)

    • Logically, the strings came from the first crappy but mandatory attempt to visualize the science for a documentary or a magazine. Science must be cool (says management), and therefore, we need full-color pictures - preferably moving pictures. Since 26-dimensional calculations are very difficult to visualize (see for example the end of Space Odyssey 2001), and you can't show the actual calculations either... Voila: strings.

      Ok. I admit... my version isn't much better.

    • So what gave us holographic theory? Was that when Bob and Bill gatewayed into meth?

      • by Pojut (1027544)

        No, that was the unfortunate night Bob decided to dose 400mg of pure DXM (in a do-it-yourself gelcap, obviously) and an eigth of Golden Teacher shrooms within ten minutes of each other.

        The story goes that he mistook a Wolverine bust for being see-through. It wasn't until he peaked, however, that he realized the Wolverine bust was not only see-through, but was in fact a projection of energy and light from his third eye.

        Thus the theory of holigraphy was found.

  • adjustments (Score:5, Insightful)

    by Tom (822) on Thursday December 16, 2010 @11:34AM (#34573984) Homepage Journal

    While you may not be able to run around claiming that String Theory is dead and disproved, evidently there are some adjustments that need to be made."

    ...again

    String theory is one of those theories that get changed around every time they run into trouble. I can't imagine what it would take to have it go away, aside from a paradigm change.

    • by Sockatume (732728)

      That's the scientific method at work. Bear in mind that string theory was constructed because quantum mechanics and relativity need some pretty serious adjustments of their own.

      • by mcvos (645701)

        How exactly does String Theory help? QM and Relativity only conflict in their predictions in areas we can't observe. In exchange we get String Theory which doesn't predict anything. Except for this, and it's been refuted.

        • by Sockatume (732728)

          None of what you have said there is true. Firstly, QM and relativity conflict fundimentally. Physics is discontinuous with scale. We get around this because the corrections are generally negligable, much as QM and relativistic corrections were negligable to scientists in the 1800s. Experiments like the LHC are reaching energies at which the corrections become non-negligable. Secondly, this is not the only prediction that a string theory makes.

    • by Twinbee (767046)
      Reminds me of the messy formulae that genetic programming creates.
    • Re:adjustments (Score:5, Insightful)

      by TheRaven64 (641858) on Thursday December 16, 2010 @11:58AM (#34574358) Journal

      String theory is one of those theories

      No it isn't. 'String theory' is an informal term used to describe a collection of theories with some common principles. Not all of them make the same predictions. It works as a pretty good filter when reading scientific journalism. Any article that contains the phrase 'string theory says' is almost certainly written by someone who doesn't know what they are talking about.

      that get changed around every time they run into trouble

      Uh, that's how science works. You observe, hypothesise, test, and then refine the hypothesis. Sometimes it takes a lot of testing before you find a case where the hypothesis makes predictions that are wrong (e.g. Newtonian gravity), sometimes it takes very little. If a theory is sufficiently high profile, a lot of effort (e.g. building the LHC) will go into testing it, so hopefully you'll find errors quickly.

      Very occasionally, someone will come up with a completely new theory that makes the same predictions as an existing one (or more accurate ones) but is simpler. When this happens, it generally displaces the old theory, but it's very rare.

      • Re:adjustments (Score:5, Interesting)

        by Dr. Spork (142693) on Thursday December 16, 2010 @01:11PM (#34575470)

        Good, I'm glad someone said this so I don't have to. As it happens, the very fact that there are so many string theories available is my #1 reason for being disillusioned with the theory. Not only does this data slow down any string theory research program, but they have not even described any possible data that could. String theories (or I should say M-theory) is so empirically slippery that it serves more as an explanatory framework and less a scientific theory.

        An explanatory framework is a normative constraint on how we should interpret the world, not a set of statements that entails to observational predictions that can be falsified. The Enlightenment view that "the universe is a clocklike mechanism" is clearly not a scientific theory, but it sort of provides a framework for things that are. They basically said "we don't want to hear any theories that don't represent the universe as a clock-like mechanism." That's why I said "normative." M-theory evangelists are best understood as people who try to commit us to a new normative framework ("we only want theories that can be expressed in 'elegant' M-theory math'), rather than to a scientific theory.

      • Lorentz ether theory [wikipedia.org] is possibly an example of an old theory replaced by a new one not because their predictions were different but because the newer was conceptually simpler.
      • by mike260 (224212)

        You observe, hypothesise, test, and then refine the hypothesis. Sometimes it takes a lot of testing before you find a case where the hypothesis makes predictions that are wrong (e.g. Newtonian gravity)

        ...and other times, the very first prediction that you test yields an instant fail.

      • Exactly. Look at evolution, the theory has evolved over time to adjust for evidence. Just because it has to change some doesn't mean it is invalid.
    • by geekoid (135745)

      All thoary shnge to adapt to new data. Newton can be falsifiad at the quanten level, that doesn't mean ti's not correct under everyday .

      What test was previous falsified string theory? Of course 'string theory' is a set of mathematical theories.

      • Re: (Score:3, Funny)

        by ColdWetDog (752185)

        All thoary shnge to adapt to new data. Newton can be falsifiad at the quanten level, that doesn't mean ti's not correct under everyday .

        .

        WARNING!

        Insufficient Caffeine levels detected!
        Cease posting immediately until situation corrected.

        WARNING!

    • Re:adjustments (Score:5, Insightful)

      by sjames (1099) on Thursday December 16, 2010 @03:55PM (#34578504) Homepage

      The problem is that the wrong field is studying string theory. It's more a toolbag of high end mathematics than a physics theory at this point. Like many things in math, it may or may not be about anything that actually exists. You can write out a bazillion arbitrary equations and use amazingly advanced techniques to solve them, but they might not mean anything.

      There are so many variations and so many "knobs" that can be adjusted that as it stands, string theory has no predictive power at all. Any result can be accommodated by making the right adjustments. Worse, having made the adjustments, any future result can still be accommodated by making further adjustments. A real theory would say "the knobs must be set this way and only this way because..." and that would yield specific predictions that could be tested.

      Consider a world where we have "polynomial theory" and we wish to discover the laws of radioactive decay. We make measurements of the intervals between decay events and plot them on a graph. With each result, we add another term to our "god polynomial" so that it fits. Provably, we can go on doing that forever and make it fit. However, at no point do we know what term comes next, so we can never actually predict an atomic decay event.

  • by line-bundle (235965) on Thursday December 16, 2010 @11:35AM (#34574004) Homepage Journal

    It shows string theory is testable after all.

    Even failing still sheds light on what is wrong with our theory (or reality if you're an economist :-).

    • "I haven't failed, I've found 10000 ways that don't work."-Thomas Alva Edison.
    • by Kjella (173770)

      Even failing still sheds light on what is wrong with our theory (or reality if you're an economist :-).

      Well the thing is there's probably one theory that is right for physics. The same is not true for economics, if people buy into the bubble there'll be a bubble and if people buy into the panic there'll be a panic so you have self-fulfilling predictions while an atom does what it does no matter what you predict. The actual trigger can be as distant as the assassination of an archduke starting a world war, and if that trigger didn't happen the whole economy could change.

      Take a look at the stock market after t

      • by dkleinsc (563838) on Thursday December 16, 2010 @12:25PM (#34574800) Homepage

        The same is not true for economics

        And there's an easy answer as to why: False theories in economics can be very profitable, and where there is large profit to be made there will be somebody trying to make it (that's one of the few settled theories of economics).

        For instance, the Laffer Curve has been consistently demonstrated to be absolutely nothing like what Arthur Laffer postulated it would be (namely, a smooth parabola) when tax rates are anywhere in between about 10% and 90%. But the Laffer Curve also motivates politicians to cut taxes, which for people who pay a lot of taxes is very profitable. So if I'm an economically rational wealthy guy who normally pays $1 million in taxes, and I can pay somebody $30,000 to tout the Laffer Curve to help convince politicians to cut my taxes by 5% (thus with a potential savings of $50,000), I'm going to do just that.

    • by hweimer (709734)

      It shows string theory is testable after all.

      Not really. What was tested here was some exotic extension to the concepts usually called string theory. If I take these concepts and add some hypothetic omgon particle that lets the universe disappear by tomorrow, then I have constructed a theory that a) makes a testable prediction and b) is probably wrong. But if we turn out to be still alive and well, then this observation doesn't tell us anything about the essentials of string theory itself, such as the presence of extra dimensions or the existence of s

  • The Hawking Singularity Detector [youtube.com] shows different results. http://www.youtube.com/watch?v=FH5Xyj0yYjs [youtube.com]
  • by jav1231 (539129) on Thursday December 16, 2010 @11:49AM (#34574250)
    I think String Theory is vital! You take the early works of Chuck Berry, Carl Perkins and move through Hendrix, Trower and later Stevie Ray and without people furthering string theory then American Idol becomes the end-all! Granted we're in a glut of String Theory progress right now but these things are cyclical. I'm confident there's another genius out there that will take strings to the next level of understanding and I for one can't wait. And as for "tiny black holes," frankly the big one behind the strumming point on the strings has always worked just fine.
  • Until it has some experimental evidence to support it, it should be String Hypothesis.

    • by fusiongyro (55524)

      Yeah, but until your ideas can be tested, they're not even hypotheses. Until today, it should have been "String Philosophy." And now it should be whatever the most politically correct term is for "theories" like alchemy.

      We need least of all another reconfiguration of this broken idea. What we really need is to find a way to offer academic amnesty for string theorists, to get them to move to the humanities department where they belong.

      • by Sockatume (732728)

        You're commenting on an article about string theory failing a test, saying how string theory cannot be tested.

  • If you make adjustments based on experimentation, then your theory becomes nothing more than
    "explaining the results" which is bad science.

    In other words, the experimenter should not say "your model failed this particular test"
    but "your model failed".

    • If you make adjustments based on experimentation, then your theory becomes nothing more than "explaining the results" which is bad science. In other words, the experimenter should not say "your model failed this particular test" but "your model failed".

      Maybe they should tack a constant on the end.

    • by Dr. Spork (142693)
      Good; wise words. However M-theory (the new name for string theory) is a cluster of freakishly many theories, each of which predicts a different sort of universe. Many of these are still consistent with the data we have, and for whatever data we could ever get, I'm sure there will be some M-theory that's consistent with that data. So M-theory as a cluster is basically immune to any kind of empirical falsification. This might sound like a good thing, but it's just the opposite.
  • "the hypothesis by String Theory that micro black holes would be formed and quickly evaporated"

    Better no black holes than black holes that didn't evaporate.
  • I haven't read Woit's post on this, but the whole idea that some guy who has for years claimed that string theory is "not even wrong" because it can't make any predictions suddenly changes his mind to say it predicted the Planck scale is below 3,5TeV is absurd.

    Some Randall-Sundrum [wikipedia.org] models might have been falsified, but I don't know enough to say whether they are part of string theory or not.
  • I remember in a math class, we were given series of numbers and we were supposed to determine the function that created them. For example:

    1, 4, 9 ,16 Obviously asking for y=x^2
    0, 1, 0, -1 Going for a sinusoidal wave

    etc. etc.

    Now, me being the smartass I am and completely bored decide to prove that an infinite number of functions can produce these series. So after digging in, figure out that if given a series of n items that I can reproduce it with at least one polynomial function with largest term of

    • I think you make a great point. With complex enough mathematical instruments you can make a model that accounts for all the data. But that opens up a philosophical question. If it does actually account for everything so well that it can't be falsified, doesn't that make it true anyway? And if we come up with any series of equations that models the universe correctly, won't brilliant mathematicians eventually come up with simplifications to it if possible?
      • by Omestes (471991)

        I think you make a great point. With complex enough mathematical instruments you can make a model that accounts for all the data. But that opens up a philosophical question. If it does actually account for everything so well that it can't be falsified, doesn't that make it true anyway? And if we come up with any series of equations that models the universe correctly, won't brilliant mathematicians eventually come up with simplifications to it if possible?

        It is a fun point. But there are several types of "t

    • by rubycodez (864176)

      this also is why the climate modeling of the "climatologists" is utter nonsense, they are forever re-cooking their books as reality doesn't support their predictions

  • by Anonymous Coward on Thursday December 16, 2010 @12:25PM (#34574792)

    I happen to be an actual theoretical particle physicist. The headline and summary are completely misleading/sensationalist and this has essentially nothing to do with string theory. If I hadn't seen the string-theory connection here on slashdot, "string theory" would not even have crossed my mind reading this. If you happen to actual read the so-called "long statement" (which is only half a page really) you would have noticed that it doesn't say anything about string theory. What this measurement has ruled out are certain theories that have some small extra dimensions that would predict these tiny black holes. Those theories don't really have anything to do with string theory per se. The only conceived connection is that string theory also has more than 4 spacetime dimensions.

    Calling this "string theory tested, fails prediction" is close to the following analogy: Someone comes up with a crazy theory according to which once a while (say 1 in 100) an apple that gets detached from a tree should rise into the sky (say by using complex numbers to cleverly generate a minus sign in Newton's laws). After having observed sufficiently many apples all fall down, we can now say with confidence that apples don't rise but in fact always fall. The slashdot headline would be: "Complex numbers tested, fail apple prediction."

    So rest assured, no string theorist will have a sleepless night and none of them will make any adjustments whatsoever. The main reaction in the particle physics world to this will be a lunch conversation along the lines of: "Told you so, this whole idea about mini-blackholes was ridiculous in the first place, in any case, glad they rule it out, so hopefully this will quiet down this whole black-hole circus now."

    • by ignavus (213578)

      I happen to be an actual theoretical particle ...

      I got this far into the parent post and my mind was already boggling.

      The things they can do in physics these days - get actual particles, and actual theoretical particles at that, to post on Slashdot.

      The marvels of modern science.

  • Okay, I'm as interested in tests of String Theory as the next guy. But more importantly, if CERN can not create mini-black holes, can we stop with all the LOLZ THE WORLD ENDZ IN 2012 LOLZ!!!!

    Is that to much to ask?

    And preemptively, If you want to reply, IT DID CREATE THE BLACK HOLES, THEY DIDN'T EVAPORATE, THE WORLD ENDS IN 2012, LOLZ!!! I should point out that if i made the black holes that don't evaporate they'll end the world before 2012. Second of all, shoot yourself. Just shoot yourself, alright?

  • ...for the cases of black holes with a mass of 3.5-4.5 TeV (1012 electron volts).

    Ok, wtf is that bit in the brackets meant to be? A conversion into "common sense" units? From terra electron Volts to ... electron Volts? But the numbers make no sense at all!! Seriously, whoever put that in, go learn some physics. Or some maths. I can't even work out what units they were attempting to convert to there. Closest I can come up with is "two-third milli-ergs" ... but that's deliberately venturing into the realm of the riduculous.

    1 TeV = 1,000,000,000,000 eV. So 3.5 - 4.5 TeV is 3,500,000,000

  • The string theory is that cats like them, or not. I don't think the cats should be in a box though, that's just cruel.
  • Does this mean I don't get my mhttp://science.slashdot.org/comments.pl?sid=1913170&op=reply&threshold=0&commentsort=0&mode=thread&pid=ini-black hole blaster?

  • Not Even Wrong points us to the arxiv prepublication for those of you well versed in Greek

    As the article is written in English, I'm trying to understand why you wrote that.

  • by bcrowell (177657) on Thursday December 16, 2010 @01:22PM (#34575648) Homepage
    The summary is completely incorrect. Whoever wrote the summary simply didn't understand the paper. String theory does not predict the production of microscopic black holes at LHC eneries. The paper's abstract says, "Limits on the minimum black hole mass are set, in the range 3.5 -- 4.5 TeV, for a variety of parameters in a model with large extra dimensions, along with model-independent limits on new physics in these final states." Note that phrase "large extra dimensions." Here [wikipedia.org] is the WP article on large extra dimensions. String theory has *small* extra dimensions: extra dimensions that wrap around on themselves at the Planck scale [wikipedia.org]. The LHC doesn't probe the Planck scale. Theories with large extra dimensions have, er, *large* extra dimensions. This experiment falsifies those theories, not string theory.
    • by bcrowell (177657)
      And here is an addendum that the Not Even Wrong blog posted after they saw that this was on slashdot:

      Update: Since this is getting wider than usual attention via Slashdot, I suppose I should remove tongue from cheek and make clear what is going on here. Claims such as the one in the 2000 Times headline always were nonsense: string theory unification failed long ago because it can’t predict anything. Various physicists back then came up with “string theory inspired” models of extra dimensions that would in principle have observable effects at LHC energies. There never was any reason at all to believe these models (and they were no more “predictions of string theory” than anything else), but there was a lot of hype about them, often promoted to the media by people who should have known better. Now that the LHC is finally working, the result is exactly what everyone expected: these exotic phenomena that had no good reason to happen don’t actually happen. It’s great evidence that the LHC is working as expected, but not an experimental refutation of string theory.

      So this should clearly establish that eldavajohn misunderstood what was going on.

      BTW, I disagree with Not Even Wrong's statement that the theories with large extra dimensions "had no good reason to happen." There is a very clear physical motivation for these theories, which is that they close the gap between the Planck scale and the electroweak unification scale. (At the risk of introducing further major c

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