Getting the story in the right order...

This Christmas I was given Brian Greene's book on string theory, The Elegant Universe (2000).

I should begin by saying that it has all of the usual problems that popular science books have for me - or at least those about physics - it waves too many hands in the air and offers too little detail. So I found it a pretty tough read. Actually, to be fair, the endnotes do offer far more of the maths - at least in summary. But then the other problem arises: I'm way behind the current maths and theoretical physics theories in that degree of detail (I was only even slightly close very briefly in the late seventies...).

Given these reservations Greene's book isn't that bad. The book begins with the well rehearsed stories of (i) special and general relativity (ii) quantum mechanics and the development of the standards model and (iii) the challenge of uniting general relativity and quantum mechanics. The big claim is that string theory looks like its meeting that challenge. The tone of voice is enthusiastic, polemic, almost millenarian. Greene pays some lip service to the possibility that string theory (really M-brane theory) won't work but clearly believes that the solution is nearly there. He's terribly excited about it all.

The real problem for me is that last year I read Lee Smolin's The Trouble With Physics (2006). Note the dates of the two books. Smolin's book is a reaction, at least in part, to the enormous sway that string theory has amongst the theoretical physics community at the moment. And it appears to have some fairly trenchant arguments against the viability of the theory itself. He is the better writer (although to be fair Greene isn't bad) and he writes as an insider about the institution and establishment as well as the science.

All of which makes Greene's book seem terribly old fashioned. He can see the complexity of the theory, it appears, but he doesn't seem to give full weight to the arguments against (at least, to someone who has read the Smolin book). Smolin writes about the excessive influence - in his view - of a very few physicists such as Edward Witten; Greene eulogises Witten uncritically and loves to cite papers he has been involved in writing. For Smolin the sociology of the institution is affecting how the physics is being done to far too great a degree; Greene seems blind in comparison.

The challenge is that because Smolin's book seems so much more subtle and sophisticated, and covers a far wider range, (and comes later), it is hard to understand and judge between the scientific arguments clearly. Of course, with the requisite maths this would be easier, I grant. However, it seemes more complex than that; Smolin's challenges are as much concerned with the interpretation of the equations (and their relative lack of experimental confirmation) as with the maths itself.

These two books were written only six years apart. What perhaps they ought to show is the speed of development and excitement of the science - but in some strange way they don't, quite. Greene's is certainly Tigger-keen on his subject, but because of that Smolin's more dour take seems to carry more weight.

What I wonder is, if I'd read Greene first, would he have been more convincing? And if I'd then read Smolin, would he have seemed more bitter and less profound?

Sigh