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String Theory in Two Minutes

Posted by samzenpus on from the the-meaning-of-life-in-1000-words-or-less dept.

An anonymous reader writes "Most of us have heard of string theory, many of us know what it is and some of us may even be experts in the field. But could you explain it in two minutes? Discover Magazine recently had a contest to do precisely that: create a two minute or less video of everything you need to know about string theory. You can view some of the best entries (video) as well as the winning video: String Ducky!"

8 of 328 comments (clear)

  1. sure why not by wizardforce · · Score: 4, Interesting

    string theory in less than a paragraph. strings "vibrate" in higher dimensional space. [specifically M-theory suggests 11 dimensions] energy states are quantised, including mass at some level. String theory's ultimate goal is to eliminate infinities and non-sensical probabilities that result from the current standard model. Also, at some level the forces merge into a single force, this force splits at lower energies which may cause some very interesting phenomenae [spatial expansion for one] one of the major hurdles to string theory is gravity. why is it as weak as it is? what are the consequences of higher dimensions to its relative strength etc. [even some theoretical work suggests gravitons leak between dimensions] very little of it is testable at the moment, one major prediction that could in principle be tested is that of varying velocities of photons according to energy/wavelength. the models suggest that a lag of around a minute or less over a distance of several billion light years while this isn't unique to string theory.

    --
    Sigs are too short to say anything truly profound so read the above post instead.
  2. I watched the video. by lordsid · · Score: 3, Interesting

    I'm a string theory expert now. not really, but I found the video informative.

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    IMAGE VERIFICATION IS EVIL!
  3. first explain it to physicists... by presarioD · · Score: 5, Interesting

    ...I'm a physicist and frankly I don't see the reason why should somebody waste time explaining a theory to the vast public that hasn't been proved right for over than 30 years now. It's quite beautiful (from the seminars I have attended) but... not verified by experiement...so... let's create some hype for the masses to consume and maybe publish a book or two and some opeds with the NYT!

    Scientific value vs. politics = 0 - 1 this morning...

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  4. IT IS NOT A THEORY!!! by Jane+Q.+Public · · Score: 3, Interesting

    String "theory" is not a theory at all, it is merely a hypothesis. It will not become a "theory" unless and until it can be tested by experiment! Come on, people! I am not nitpicking: the scientific among you know the difference. Do not accept the name "string theory" at face value. That is just String Propaganda.

    And if that were not bad enough, there are other hypotheses, such as MoND (Modified Newtonian Dynamics) that explains most if not all what is explained by the string hypothesis, without having to imagine all those other dimensions. In fact, it is so much simpler than the string hypothesis that Occam's Razor is practically screaming, "No! Over here, you idiots!"

    Yes, there are problems with MoND, but there are very big problems with strings as well. The fact that an idea is popular in the media or has been around longer is not evidence that it is true, any more than the others.

  5. Re:A modern day fairy tale by wizardforce · · Score: 5, Interesting

    Cosmological theories are currently not much better than intelligent design - you just have to take them on faith.
    except string theory is based on some very complicated math and heavily encrusted in physics, intelligent design on the other hand is an attempt to justify the writings of biblical authors over 2,000 years ago there is a clear difference.

    Different versions of the string theory can not even agree on the number of physical dimensions that exists. They are basically just playing with numbers to try to match the observed strength of gravity.
    after you do the math it works out that if you don't have supersymmetry you need precisely 26 dimensions to fit what we observe, with supersymmetry you only need 10 or 11, the 11th unique to M-theory seems to explain phenomenae predicted by the 5 major string theories common a few years ago. it does make predictions although at the moment the number that we can test are very small, this will change as we get better at observing higher energy events and work out more of the math.

    Not to mention that our existing physics only explains 10% of gravity in the universe. Talk all you want about dark matter, but this leaves the possibility of pretty dramatic flaws in our current theories.
    except that we have observed objects in the universe that seem to have wrenched dark matter out into the open, free of most of the visible matter. we still see the gravitational lensing effect of this matter which allows us in effect to map dark matter in that region.

    The biggest flaw in current cosmology is why we are not trapped in a singularity of a universe-mass black hole. Certainly for long time after big bang the universe was inside its own Schwarzschild Radius. Why didn't it just collapse right back after the big bang? After all, it would take an infinite force to escape the event horizon. Oh right, something caused "space" to mysteriously expand, just like now some unspecified dark matter keeps stuff from expanding. It sounds like we need more work to get to the standard of scientific theories.
    space is in fact expanding, not only that but the expansion is accellerating over time. space isn't theoretically expanding, it litterally is expanding at great velocity. although at the same time, there is growing evidence that certain higher dimensional phenomenae could be responsible for this expansion and even the kind that caused the big bang [if causality even means anything at that point] but there is a very important thing to learn here, there is never ever an infinite force, there is a limit to the magnitude of a force, gravity is likely to be quantised as well, which probably means that there is a finite limit to spatial curvature. the concept of an infinitely dense mass may also not even exist if there is a finite quantised limit to spatial curvature. we have a few years or less before we can start really testing some of the predictions of quantum gravity and string theory in general, if we're wrong, we learned from it and can better understand the universe because of it.
    --
    Sigs are too short to say anything truly profound so read the above post instead.
  6. Why Heim Theory is better then Strings by Zdzicho00 · · Score: 3, Interesting
    Achievements of Heim theory: http://en.wikipedia.org/wiki/Heim_theory
    1. EHT (Extended Heim Theory) allows to easily calculate particle masses using only some physical constants. You can check this Heim Mass Calculator: http://www.daimi.au.dk/~spony/HeimMassFormula/HeimCalculator
    2. Succesful prediction of masses of neutrinos.
    3. Prediction of Heim-Lorentz force which most likely is being observed in ESA experiments performed by Dr. Martin Tajmar. During these experiments artificial gravity is being created.
    4. Reasonable explanation why CMB Cold Spot appears to be cold without mumbling about Dark Matter/Dark Energy, thanks to Heim's corrected gravitional law.
    5. EHT explains why it appears that there is not enough mass observable in the Universe without using Dark Matter concept.
    6. EHT most likely explains weird effects measured during Gravity Probe B experiment, see: http://www.hpcc-space.de/publications/documents/FieldPropulsion.pdf.
      These effects are in agreement with Martin Tajmar findings, see: http://arxiv.org/pdf/0707.3806
    7. Droscher&Hausner paper about space propulsion based on Heim theory http://www.hpcc-space.de/publications/documents/aiaa2004-3700-a4.pdf was awarded by AIAA in 2004.
    Now, I would like to ask a question.
    Are there any similar achievemets of Strings Theory?
    If you want to know more about EHT please refer to wiki page and this huge discussion thread.
    /Z
  7. Re:A modern day fairy tale by bsmoor01 · · Score: 4, Interesting

    if we're wrong, we learned from it and can better understand the universe because of it. This is the point the grandparent poster completely doesn't get. Science is about creating theories based on experimentation and observation. Once a hypothesis has been proved to predict outcomes consistently, we say "That's got a really good chance of being true." and we run with it. That doesn't mean it's not wrong, and that's just *fine*.

    If we learn something new that blows an old theory away, we start with new hypotheses and continue from there. We use it as a learning experience to continue exploring what makes things tick. The anti-science rhetoric of the creationists think this is a flaw, which always confused me. Creationists want everything to start and stop with the idea of god, which isn't even a hypothesis (it's totally untestable!). How a creationist can be happy with such a non-answer as 'god' is astounding to me, personally. The concept of god answers no questions, and encourages us to stop looking for answers.
  8. Re:No... by ceoyoyo · · Score: 3, Interesting

    I agree with most of what you said, but with a couple of modifications.

    A scientific theory is falsifiable, yes, but not necessarily easily falsifiable with current technology. If we need a bigger particle accelerator to falsify it then it's still a theory. Things like ID are non-falsifiable under any circumstances because no matter what you observe there's always an escape hatch -- God is screwing with you.

    It's pretty hard to think up an experiment to test the "macro"-evolution that creationists are always harping about, and most of more general evolution is pretty hard to test as well. That doesn't mean evolution isn't a theory.

    I'm not going to address whether string theory is over hyped or over funded. That's a political question. It is a theory, actually a collection of theories. Falsifiable predictions are also starting to be made using it. Some members of the string theory family have been pretty much discarded because they don't hold up, and other members of the family are being tested by experimentalists as we speak. They predict photons of different wavelengths will travel at slightly different speeds, and some versions predict that the extra dimensions are big enough to be observed by recent attempts to measure the gravitational constant for very small objects.