Strings without strings

Both Philip Gibbs and Peter Woit have commented Strings 2011 conference held in Uppsala, Sweden. For some reason Lubos Motl has not noticed the conference although one might think that the superstring fan number one would be its most zealous humble correspondent;-).

A short side remark: I have never been in Uppsala. It however stimulates in me some rather emotional mental images: one of the participants in the organizing committee is a professor in Uppsala and was the second one of two young professors whose statement about my work destroyed me professionally and made me unemployed for the rest of my life.

I recommend the posting of Peter Woit for anyone wanting to get idea about the general situation. The opening talk of David Gross contained the usual hype. Gross claimed the field is “extremely healthy”, “vibrant and exciting”, “making enormous progress in a variety of areas’”, with “stupendous progress” in N=4 planar SYM (just with this statement, which is not about string theory, I can agree). Gross admitted that string theory is a failure on the experimental side. Optimistically Gross noticed that "The most important product of knowledge is ignorance" but added “After 43 years of string theory , it would be nice to have some answers.”

In his conference summary Jeff Harvey said about string theory "It is not dead, it only sleeps" (friends of Monty Python remember the eager bird seller trying to sell a dead parrot). One of the participants- Chris Hull- wondered how little Strings 2011 was about strings. Paraphrasing Wheeler, Strings Without Strings 2012, might be a more appropriate title for the next conference. It is clear that string hegemony is making a graceful exit and it takes years to make this smoothly. Twistor approach - nothing to do with strings - is indeed extremely vibrant and developing approach and -most importantly- is well-defined so that it does the degenerate to endless conjectures about dualities between various non-existing formulations of a non-existing theory. Twistors provide the badly needed emergency exit for the string theorists and this is good.

The basic problem of string theory indeed is that there is no M-theory or string theory. How it could be otherwise since no general principles have been formulated. People have been busily producing technical results using the methods borrowed from existing mathematics instead of concentrating to questions about fundamentals. Physics is really difficult and the outcome of lifetime of thinking can be just an abstract principle which for the post-modern referee of the respected journal looks just crackpottery as compared with the impressive outcome of a massive calculation using a highly refined computerized method, which is basically just an application of existing algorithm. Strings are argued to provide inspiration for deriving mathematical results. I have no doubts about this: physicist's view provides a valuable complementary approach to the mathematical problems.

My hunch is that super-strings and M-theory will be one day admitted to be just an idealization of super-gravity in 10 or 11 dimensions using extended objects of various dimensions just as the basic argument allowing to assign p+1-forms to p-branes as generalizations of gauge potentials demonstrates. At quantum level this association is a fatal mistake since it is inconsistent with Uncertainty Principle. The use of charge distributions concentrated on surfaces of various dimensions - the branes - provides a powerful intuitive tool for deriving purely mathematical results about topology but does not have much to do with physics.

It is rather fair to repeat what I said for about 24 years ago- about two years after my thesis - as I wondered how it is possible that highly educated human beings can take seriously so incredibly stupid and ugly idea as spontaneous compactification is: string theory as a physical theory is dead. This is finally implicitly admitted also by the conference participants as is clear from what they are actually doing.

What next? I have some ideas about this but there are sociological factors involved;-). Doing some violence for Bohr's well-known saying so that it applies in the post-modern situation: "Before a new theory can be accepted, its proponents must be dead". In the recent situation the good news is that there is just one proponent and he is already sixty years old but I am afraid that we must just patiently wait at least one decade and in the worst case two;-). If the proponent is as long-lived as his mother, we have to wait for 34 years! Sad from the point of view of physics point of view but we must understand that the laws of sociology stand above the laws of physics in the academic hierarchy. The world of Dostojevski's "The Brothers Karamazov" is full of irrationally behaving characters but is only a Kinder Garten as compared with the academic world.