Monday, April 2, 2007

JYI Article- String Theory

My science journalism post slogs ever onward with a new report from the front- The Great Debate: String Theory. (Yes, that title is blatantly stolen. No, I am not telling you where from if you don't recognize it.) It's sort of an attempt at an objective overview of string theory and the like, including some pithy quotes from both pro and anti string physicists.

My conclusions on the topic by the way run something like this- string theory is rather nice and cute and probably teaches you a lot about theory in general, but my experimental self wonders why it doesn't belong more in the math department. I've spent too much time in physics labs I suppose, but I like experimental evidence. It keeps you in check when you mess up, and I am humble enough to know that I mess up all the time.

Interestingly, there is a long conversation right now going on over at Cosmic Variance on if String Theory is Losing the Public Debate. I'm going to go out on a limb and say yes- in my experience you have a lot of people who understand the scientific method and not enough pro-string arguments heard right now, so string theory is obviously going to suffer. And I think it's good to force string theorists (or any field, really) to go out and defend themselves on occasion if they accept public grants. Wouldn't it be rather high-minded to take a check without justifying it on occasion to the people footing the bill?

3 comments:

nige said...

"... I think it's good to force string theorists (or any field, really) to go out and defend themselves on occasion if they accept public grants. Wouldn't it be rather high-minded to take a check without justifying it on occasion to the people footing the bill?"

Can we suspend disbelief for a moment and suppose that string theory is a kind of religion (like epicycles, phlogiston, caloric, mechanical aether, vortex atoms, cold fusion...).

Would that hypothesis explain why Dr Witten advises string theorists not to defend themselves from rational arguments in science (similarly, the Pope advises priests not to engage in religion-versus-science controversy):

‘String theory has the remarkable property of predicting gravity.’ - Dr Edward Witten, M-theory originator, Physics Today, April 1996.

‘For the last eighteen years particle theory has been dominated by a single approach to the unification of the Standard Model interactions and quantum gravity. This line of thought has hardened into a new orthodoxy that postulates an unknown fundamental supersymmetric theory involving strings and other degrees of freedom with characteristic scale around the Planck length. [...] It is a striking fact that there is absolutely no evidence whatsoever for this complex and unattractive conjectural theory. There is not even a serious proposal for what the dynamics of the fundamental ‘M-theory’ is supposed to be or any reason at all to believe that its dynamics would produce a vacuum state with the desired properties. The sole argument generally given to justify this picture of the world is that perturbative string theories have a massless spin two mode and thus could provide an explanation of gravity, if one ever managed to find an underlying theory for which perturbative string theory is the perturbative expansion.’ – Peter Woit, Quantum Field Theory and Representation Theory: A Sketch (2002), http://arxiv.org/abs/hep-th/0206135

‘The critics feel passionately that they are right, and that their viewpoints have been unfairly neglected by the establishment. ... They bring into the public arena technical claims that few can properly evaluate. ... Responding to this kind of criticism can be very difficult. It is hard to answer unfair charges of √©litism without sounding √©litist to non-experts. A direct response may just add fuel to controversies.’ - Dr Edward Witten, M-theory originator, Nature, Vol 444, 16 November 2006.

Yvette said...

A religion? That's an interesting one... you could probably get away with the argument, but I think that's a little harsh- string theory produces some great math, but we don't accuse all mathematicians of being priests.

Also one of my favorite quotes comes to mind- "Physics isn't a religion. If it was, we'd have a lot easier time getting money." :)

Anonymous said...

Can we suspend disbelief for a moment and suppose that string theory is a kind of religion (like epicycles, phlogiston, caloric, mechanical aether, vortex atoms, cold fusion...).


Unlike string "theory" , epicycles, phlogiston,caloric, and the aether were (incorrect) attempts to explain observed phenomena. At least they were based on observations and ,despite being wrong, were closer to legitimate scientific models than strings. After 20 years, so-called string theory has yet to produce anything testable ( much less falsifiable). Where are all these "extra dimensions"? Oh, they're rolled up into small manifolds way too tiny to ever be observed! How convenient!! Well, gee, there's some distant galaxy with planets made of green cheese - I guess I'm now qualified to be a string theorist :)

String theory is much closer to religion than epicycles - even the leading proponent of strings, Ed Witten, is referred to as "The Pope".