Paul Davies: 'Crisis' might be overstating it, in my opinion. Is there really a crisis, according to this book? Compulsive reading isn't really a dismissal or an affirmation, it just says it's a good yarn.
Robyn Williams: Well, 'not even wrong' says Peter Woit, and he seems to imply that there is a crisis, and I see 'compulsive reading' says Roger Penrose from Oxford, I think you know him well. So it looks very wonderful but it's not complete, nobody has yet written down the final theory, let alone solved it.
The one force that's been really hard to shoehorn into any sort of unified scheme is gravitation, and string theory gives what seems to be a consistent account of gravitation as well. The mathematics is pretty horrendous, but the calculations that have been done so far suggest that not only do all the particles we know and love fit into this scheme but all the forces do as well. So all the different particles are not separately fundamentally different things, they're just the same thing wiggling in a different way, and it's a beautiful idea. This was a big departure from 2,500-year tradition that assumed that the fundamental building blocks of all matter would be particles, but why not strings?Īnd it turns out that little loops of string.and I mean little, I'm talking 20 powers of 10 smaller than an atomic nucleus.little loops of string could explain all these particles and they would explain them simply because if a loop of string is small enough it would appear like a point particle, and if a string wiggles this way it could be an electron, if it wiggles that way it could be a neutrino, and so on. When you make a list of all these things it's still rather disappointingly long, so 20 or 30 years ago people thought maybe there's a deeper level of reality, and they came up with the idea that these would be strings. They're composite bodies with bit and pieces inside and if you keep going down and going down, you get down to the level of things we call quarks, and then there are the electrons which are familiar. Now, the things we call atoms today, we know are not truly fundamental. Paul Davies: The idea that beneath the complexity and diversity of nature is some sort of simple fundamental building blocks goes right back to ancient Greece, it's a 2,500-year-old idea. Robyn Williams: Before we go into his argument, are there really supposed to be strings out here, even little ones or huge ones? I've heard them describe possible strings that span the sky.
And the question is how long do a lot of very clever people beaver away on this before they say enough is enough, or will they in fact get there, is success just around the corner? And this book is written in that context, and the author clearly feels that too many resources have gone into this particular program and it's denuding the rest of theoretical physics of talent, and that probably at the end of the day this is time, money and talent wasted. And, I suppose, what can one say about this program other than 'nice try', they're not there yet. I should explain that string theory is an attempt to pull together all the disparate branches of fundamental physics into some sort of wonderful, final, unified theory, maybe, we hope, a formula you can wear on your t-shirt. It's been sort of an on-again, off-again program that has really gripped the physics community like nothing that I have known, so there's a huge element of faddism involved. Paul Davies: I've lived with this string theory phenomenon for a large part of my career, even wrote a little book on it in the 80s so it shows how far back it goes. Not Even Wrong is the title and the subtitle says it all The Failure of String Theory and the Continuing Challenge to Unify the Laws of Physics. So to another professor of physics, Paul Davies, who's been reading a book that's made a big ripple around the world. Robyn Williams: Gerry Carrington is head of physics at the University of Otago, Dunedin, New Zealand.
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