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Test for String Theory Developed
inexion writes "PhyOrg is reporting that SLAC (Stanford Linear Accelerator Center) scientists have found a way to test the revolutionary theory, which posits that there are 10 or 11 dimensions in our universe. This past December, Joanne Hewett, Thomas Rizzo, and student Ben Lillie published an article in Physical Review Letters which shows theoretically how to measure the number of dimensions that comprise the universe. By determining how many dimensions exist, Hewett and Rizzo hope to either confirm or repudiate string theory under specific conditions which would consist of creating and examining 'micro-black holes', which could be formed by smashing two high energy protons together. Using the predicted decay properties of the emitted neutrinos, Hewett and Rizzo solved equations to find that our universe may have more than 10 or 11 dimensions -- too many dimensions to be explained by string theory."
Evolutionary "theory," for example, has a substantial quantity of data that suggests the general notion is true. But string theory, at least in the scientific community, does not maintain the same support that most other "theories" have. There are, rather, a number of prominent physisists who believe string "theory" doesn't deserve the theoretical status it has obtained (or at least that's what I've been led to believe).
The question I have, therefore, how was the "theory" part conferred?
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You may not believe this, but the English language is often ambiguous. Some words have two, three, four, or more meanings. The word theory is one of those. One definition of theory is a widely tested and accepted set of principles, as in Einstein's theory of relativity, which gives specific predictions about the universe that have been time and again proven correct to a high degree of accuracy. Another definition of theory is a hypothesis that has not yet been verified, as in string theory, which has not been scientifically verified at all. Yes, this ambiguity causes no end of confusion when one refers to the "theory of evolution". Many of us sit back and chuckle as people refer to it as "just a theory".
What a fool believes, he sees, no wise man has the power to reason away.
It is a theory in the mathematical sense similar to Group Theory, Set Theory, or Ring Theory. In mathematics these "theories" really refer to the specific set of axioms assumed. There exist some axioms (well, really, assumptions) that define the body of work that is "string theory". But one should not confuse string theory for mathematics. There are few rigorous proofs in the literature, a very large set of assumptions, and a large set of unproven conjectures.
In practice, unless a very bizarre set of miracles occur (such as the fundamental scale of gravity being much, much lower than we measure it to be -- such as is assumed in the article), there is no way we will ever conclusively prove string theory to be correct. It will always be possible to write down a different theory which gives the same physics, but is far simpler. String theory is not falsifiable and therefore is unlikely to stand the test of time. (or, maybe, it will live forever -- kind of like dragons and vampires)
-- Bob
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
>how was the "theory" part conferred?
There is no governing body that certifies theories. Saying something is a theroy does not specify how certain it is, how close it is to the "truth", how popular it is, how accepted it is within a group, how does it compare to other theories, how close it is being falsified. "Being worthy of academic discussion" is another idea.
(Some people would be scared because of this, saying that it makes science weak. But it doesn't, because science is about being open to ideas and exploring them, which means that everything is open, even to "crazy ideas" like string theory which should be evaluated and proven/disproven by its merits along, not on some title given by a set of people.)
The surprise isn't how often we make bad choices; the surprise is how seldom they defeat us.
One should really call it String Hypothesis or String Postulate.
In cases like this, untested ideas about the function of the universe, I personally like the term "model." You can use it to posit the inner workings of the universe and why things happen, but untill the technology is there and the experiments have been run it is not fully a scientific theory. But I believe it does fall within the bounds of model. And the nice thing about this is that with a model, you can make some assumptions that may or may not be true to simply explore how the world would work supposing this is true.
My favorite correlary is light. We have a model of light behaving as a wave, and that model has been proven to be wrong under certain cirumstances. We have a model of light behaving as a particle, and that model can also be proven wrong under certain circumstances. However, the fact that each model is not completely correct does not mean that they are useless. The basis of the model can be used to make further predictions about the way the world works, or even to produce technology through engineering.
I'll never make that mistake again, reading the experts' opinions. - Feynman
> isnt anything that is purported to be true as a result of some a mathematical proof a theorem and something that is known to be true but has no proof a postulate(Law)?
Notice that "theory" and "theorem" are different words. Theorems arise from applying rules of inferences to sets of axioms (and previously proven theorems).
In general, the empirical sciences work by induction and hypothesis testing rather than by applying rules of inference to known truths, and thus don't produce theorems.
As others have pointed, there are several meanings of the word "theory", even in the world of science. I don't know the history of it, but I suspect "string theory" is called a theory because of its very mathematical nature, like "computational complexity theory".
Also, I suspect we will continue to call it "string theory" even if it is eventually shown to be wrong.
I'm not crazy about that choice of names for it - we don't have any problems naming GR or QM without putting "theory" in the name - but language and terminology seem to have lives of their own.
Sheesh, evil *and* a jerk. -- Jade
>> By determining how many dimensions exist, Hewett and Rizzo hope to either confirm or repudiate string theory
You cannot confirm a theory.
An experiment can either support it or disprove ("repudiate") it.
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In that case, this also fits the theory of evolution. Evolution attempts to explain the past, but what predictions does it make of the future than could be checked out by experiment?
You are joking, right? The Theory of Evolution does not "attempt to explain the past" - it attempts to explain how one can get from point A to a later point B. We just happen to have mostly developed and verified the theory by looking at As and Bs that are in the past.
When one has access to an overwhelming amount of past evidence that can be compared against, one doesn't need to wait the 10s of millions of years necessary to see if it happens again.
That anyone doubts the truth of Evolution anymore I see as an astonishing failure of the school system.
one doesn't need to wait the 10s of millions of years necessary to see if it happens again.
The drawback of only having historical data is that there are quite a few holes in that data (IOW the sampling rate is rather low).
Using this data we don't get to see evolution in action, we see only the end result of what we assume/theorize must be evolution.
So in this case, yes we would benefit from 'seeing if it happens again'.