Because the strings that are said to quiver at the
core of elementary particles are too small to detect —
probably ever — the theory cannot be experimentally
confirmed. Nor can it be disproven: Almost any
observed feature of the universe jibes with the
strings’ endless repertoire of tunes.
In that case, it's not science. At most, mathematics.
I really don't agree with that conclusion, though I recognize that it's not far from the traditional definitions of science.
The point is, let's pretend for the sake of argument that this article's main idea winds up being absolutely true: imagine that someone produces a rigorous mathematical proof that any consistent physical theory that incorporates both quantum mechanics and gravity (general relativity) must be some variety of string theory.
Now, we live in a universe where quantum mechanics is an experimental fact, and we live in a universe where general relativity is an experimental fact (each within their own domains of experimental accessibility). Would it truly be unscientific at that (thus far imaginary) point to conclude that string theory was a correct description of reality? The only alternative that I could see would be to abandon the idea that mathematics is able to describe our universe at all. And that doesn't feel like science, either.
[Note: As a professional string theorist, I'm hardly a disinterested party. But it does mean I spend a lot of time thinking about this stuff.]
Yes, that is what Peter Woight at Columbia keeps saying on and on: http://www.math.columbia.edu/~woit/wordpress/. It is a sad world in which scientists dare (in the XXI Century) call "science" something which cannot be either verified of falsified...
(I am not a string theorist.) String theory makes plenty of testable predictions, they just aren't new so it has to compete with Quantum Mechanics. It gets into questions of how to choose between multiple theories that make the same predictions.
Scientists need to admit the possibility that their theories are wrong, but that cuts both ways. Just because a theory seems untestable today, that does not mean it is guaranteed to be untestable forever.
If a theory is internally consistent and its predictions match known empirical evidence, then the theory is supported by that evidence just as much as any other theory is. That does not provide a reason to prefer it over other theories, but by itself that is not a reason to dismiss it.
The way I understand it (and I am probably completely wrong, seeing as I am not a physicist, nor a mathematician), string theory is to scientific theories as a class is to objects in OOP.
You can indeed never falsify string theory itself, but you absolutely can falsify a theory derived from string theory by picking parameters for it.
Strictly speaking, nothing can ever be confirmed or disproven, for random events in the universe can always spoil any experiment. QM, by its statistical nature, actually destroyed the definition of science. We can only speak of how likely we believe that something about the physical reality is true.
I used to work with Mukund (Rangamani) and Veronika when I was doing my PhD at Durham Uni (2004-2008) -- it's great to see the work they and others are continuing to do on this. It formed the basis for my thesis (http://etheses.dur.ac.uk/2906/), and Anti de-Sitter spacetimes allow for some great visualizations (I spent much time working in Mathematica to produce the one shown in the slide here: http://bethnalgreenventures.com/2013/08/05/guest-blog-from-m...).
You also learn something new everyday - I'd never come across the term "Fisheye Universe" for AdS space before! :)
[+] [-] mirimir|11 years ago|reply
[+] [-] Steuard|11 years ago|reply
The point is, let's pretend for the sake of argument that this article's main idea winds up being absolutely true: imagine that someone produces a rigorous mathematical proof that any consistent physical theory that incorporates both quantum mechanics and gravity (general relativity) must be some variety of string theory.
Now, we live in a universe where quantum mechanics is an experimental fact, and we live in a universe where general relativity is an experimental fact (each within their own domains of experimental accessibility). Would it truly be unscientific at that (thus far imaginary) point to conclude that string theory was a correct description of reality? The only alternative that I could see would be to abandon the idea that mathematics is able to describe our universe at all. And that doesn't feel like science, either.
[Note: As a professional string theorist, I'm hardly a disinterested party. But it does mean I spend a lot of time thinking about this stuff.]
[+] [-] pfortuny|11 years ago|reply
[+] [-] stolio|11 years ago|reply
For more info, Leonard Susskind (one of the theory's founders) has a lecture series on it here: http://theoreticalminimum.com/courses/string-theory/2010/fal...
I haven't watched them but they're likely to involve upper level undergrad or graduate level math.
[+] [-] snowwrestler|11 years ago|reply
If a theory is internally consistent and its predictions match known empirical evidence, then the theory is supported by that evidence just as much as any other theory is. That does not provide a reason to prefer it over other theories, but by itself that is not a reason to dismiss it.
[+] [-] Xixi|11 years ago|reply
You can indeed never falsify string theory itself, but you absolutely can falsify a theory derived from string theory by picking parameters for it.
[+] [-] kriro|11 years ago|reply
[+] [-] amelius|11 years ago|reply
[+] [-] JohnHammersley|11 years ago|reply
You also learn something new everyday - I'd never come across the term "Fisheye Universe" for AdS space before! :)
[+] [-] unknown|11 years ago|reply
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