Current Thoughts in String Theory

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Current Thoughts in String Theory

Posted by michael on Tuesday September 2, 2003 @08:07AM from the elephants-all-the-way-down dept.

DrLudicrous writes "The NYTimes is running a nice little synopsis of the current ideas in string theory. Apparently, there is still quite a bit of disagreement about how to interpret the various theories, with some string theorists supporting a semi-deterministic worldview a la Einstein (God does not play dice), while others believe our universe is just one possibility among many, with respect to various physical parameters."

15 of 391 comments (clear)

Fringe science, or valid? by mao+che+minh · 2003-09-02 08:07 · Score: 5, Interesting

Considering that we presently greatly lack the amount of energy required to test even the smallest of superstring theory claims, this debate is merely beginnning. Frankly, I still view superstring theory as a fringe science, considering the fact that it holds merit (many of it's hypothesis are built upon solid scientific foundations), but none of it's claims can yet be tested and verified.
Still, intriguing stuff.
1. Re:Fringe science, or valid? by Eric+Ass+Raymond · 2003-09-02 08:20 · Score: 5, Informative
  
  Enstein's theories were also empirically unprovable until recent advances in avionics, minaturization, and electronics.
  Bollocks. Einstein's relativity could be readily tested at the time by measuring the bending of the light by Sun's gravity. That's exactly what made them so strong and actually respected by the experimentalists.
  To an experimentalist a theory is just hot air until it can be tested in practise.
  
  --
  BOO! TERRO
2. Re:Fringe science, or valid? by corbettw · 2003-09-02 08:41 · Score: 5, Funny
  
  "Frankly, I still view superstring theory as a fringe science, considering the fact that it holds merit (many of it's hypothesis are built upon solid scientific foundations), but none of it's claims can yet be tested and verified."
  
  This is why I prefer sillystring theory. You can easily prove or disprove the effects of sillystring in a great many environments. For example:
  
  1) If I shoot sillystring at the hot blonde across the room, will she sleep with me, or slap me?
  2) How slow must I drive on the freeway to enable me to shoot sillystring, and still have it maintain cohesion enough to obscure another driver's windshield completely?
  3) If I replace my roommate's shaving cream with sillystring, how many times will he cut his face before he realizes the switch?
  
  You see? Definite, provable, questions. None of thos "alternate universe" or "quintuple bajillion watts of energy" problems.
  
  --
  God invented whiskey so the Irish would not rule the world.
3. Re:Fringe science, or valid? by Dashing+Leech · 2003-09-02 08:58 · Score: 5, Interesting
  
  I'm not sure I'd completely agree with that. True, that sort of test would be ideal. However, while it is true we can't synthetically test it, that's not always necessary for it to have scientific value.
  Science isn't so much about finding the "material truth", it's about finding an appropriate "model". For instance, Newton wasn't wrong per se, his model was just incomplete. We still use his model for predicting the majority of practical behaviours outside of experimental physics. Einstein came up with a better model, but we know it isn't complete because relativity and quantum mechanics are not compatable. Still, those models work in their respective applications.
  If superstring theory is able to work at predicting all behaviour we can observe, it doesn't really matter if the concept is correct. In other words, if two different phenomena (conceptually) always produce the exact same results, does it matter if our model is based on the "real" one or the ficticious one?
  True, there is a desire to know the "truth" of a given situation, but a model that works for all observable phenomena is certainly sufficient for most reasons we use science. Requiring that we create a phenomenon that we can't normally observe is useful for testing the truth of the model, but not necessary its practicality.
Free Link by Anonymous Coward · 2003-09-02 08:08 · Score: 5, Informative

Link
Mirror by Anonymous Coward · 2003-09-02 08:09 · Score: 5, Informative

In case the site is slow, or you don't have a stinking NYTIMES account, here is a mirror.

Martin Studio Slashdot Policy
Good Info on String theory by gsparrow · 2003-09-02 08:13 · Score: 5, Informative

This site is maintained by a professor and has a great book on string theory. http://www.mkaku.org/
Yes but no by Raul654 · 2003-09-02 08:14 · Score: 5, Informative

You are correct in stating that we lack the energy to test string theory -- According to Hawking, one estimate of the (theoritcal) grand unification energy would be a thousand million million million GeV. Further, he goes on to say that it would take something the size of a solar system to produce this. So you're right, we can't do it.

BUT, there could very well be places that do have this necessary energy and could be observed to exhibit traits that we can measure and confirm theories with. This has been how most of the more recent unification theories have been confirmed -- either by measuring very small things with very fine equipment or measuring very large things in space.

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To make laws that man cannot, and will not obey, serves to bring all law into contempt.
--E.C. Stanton
on pseudorandom oscillation by Anonymous Coward · 2003-09-02 08:14 · Score: 5, Funny

My housemate was recently developing a comprehensive theory of the oscillations of short bits of string, even comprising such philosophical points as whether they're inherent or caused by some bored unemployed minor god. Then I bought a laser pointer and now it's all refraction this and speckle that.

Cats are fickle.
Einstein quote by nanojath · 2003-09-02 08:18 · Score: 5, Insightful

The theory yields a lot, but it hardly brings us any closer to the secret of the Old One. In any case I am convinced that He does not throw dice. --Einstein, writing to Max Born, 4 December 1926.

I think that quote (or rather, truncuated paraphrases thereof) is much abused. What Einstein is saying (which is much clearer in a fuller context) is that while the probabalistic equations that comprise much of quantum theory are valuable as descriptive and predictive tools, they do much less to further Einstein's cherished ideals of really understanding the fundamental basis of physical reality. The statement "I am convinced that He does not throw dice" is a statement that while the equations of quantum mechanics might behave like statistics, they did not mean that the underlying reasons for why these equations work were simply artifacts of random, statistical processes - mere throwing of dice. Our ongoing failure to connect all the dots of the various paradigms could indicate that he was on to something...

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It Is the Nature of Information to Transgress Artificial Boundaries
A challenge? by Empiric · 2003-09-02 08:19 · Score: 5, Funny

Maybe god is like some kind of ubercoder, daring us to figure out his implementation.

And like most of them, he doesn't document.

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~ Whence do you come, slayer of men, or where are you going, conqueror of space?
People with issues... by Anonymous Coward · 2003-09-02 08:47 · Score: 5, Insightful

There are several overlooked points in the discussion. Someone above has already pointed out that the Einstein quote about divine gambling is over and misquoted.

String theory was proposed by Lord Kelvin, who started to investigate by developing a theory of knots, which was expanded by Reidmeister, and blossomed in the 20th century.

Einstein's special and general relativity were created to explain observed phenomenon that could not be explained by current theories. For special relativity, this was the constant velocity of the speed of light given by electromagnetism and confirmed by the Michaelson-Morley experiments. General relativity is a result of formulating Newtonian gravity in the field theoretic language used for unified electromagnetism. There were bits of data around indicating its necessity, though, such as errors in the perihelion of Mercury.

Quantum mechanics was similarly developed because of an incredible plethora of data. Thanks to Bell, we now know that (unless theory takes some really extreme turns), before an interaction with a "classical" apparatus, a quantum particle not only has unknown position and momentum, it actually doesn't have either. It's a subtle argument, but it's pretty well tested.

The motivation for string theory was to remove infinities in the fields which result from point-like particles. There is no physical motivation. String theory was not formulated as a theory of gravity or a grand unification theory. Those were bolted on afterwards as people noticed they could have sufficient degrees of freedom: you can build similar theories with straight up quantum field theory, and many people do for their life's work. So far the theory has produced one observable, which we already knew to far higher accuracy from quantum field theory. Pure number theorists get more physics as a by product than do string theorists. Supersymmetry and the Higgs boson are attempts to clean up mathematical holes, but they seem almost well motivated compared to the morass that is string theory.

String theory has driven a wedge between theorists and experimentalists in particle physics, and made it "unfashionable" to do serious theory that actually deals with reality. However, the popular press loves it: you can quote big sounding names and no one can nay-say them. Most areas of particle physics abjectly fail when it comes to explaining what you're doing to the layman.

Thankfully the pendulum seems to be swinging. At Caltech, their one phenomenologist has recently been absolutely swamped with pupils: string theory seems to be dying off at last.
Re:Theory vs Reality by apetime · 2003-09-02 08:52 · Score: 5, Insightful

While various Theories of Everything are being proposed, a lot of them are not based on observation. They are just complex mathematical magic created to explain reality.

The observation is that there are two fields of physics that have been rigorously tested and widely accepted, but are only really valid in their own domains. The problem that faces modern physics is how to reconcile this disagreement. The difference between string theory and turtle theory is that string theory is reduces down to quantum theory and relativity when suitable constraints are placed on it. Stop me if I'm wrong, but I don't think turtle theory can do that. The fact that current technology is unable to verify the theory through experiment is a temporary situation (and a unique one. Through most of history, experimental observations have triggered theoretical research.)
String theory might be pushing the limits of science, and it might be completely wrong, but it has a strong foundation, and it attempts to address a big question, and that should be reason enough for scientists to keep working on it.
Re:String Theory by Anonymous Coward · 2003-09-02 09:08 · Score: 5, Funny

The most important part of String theory is the null terminator%#@%(&(*(FA(EWUA(UF#(A@JI#J^IHITHAIUG(#A @U(T#@(*(^@U#IHTIAWHIHJT#(@AU&%(#@
Primer to get you up to speed on current theory by Nova+Express · 2003-09-02 09:18 · Score: 5, Informative

I know more about string and particle theory than 99% of the population, which means I'm still a comparative dumbass on the subject in relation to people who really know what they're talking about.

However, here's a spiffy chart of the current "standard model" to help people get up to speed. Especially helpful for those who don't normally deal with Mesons and Antibayrons on a regular basis...

--
Lawrence Person (lawrencepersonh@gmailh.com (remove all "h"s to mail)
http://www.lawrenceperson.com/