This past week there has been a conference going on in Cambridge called Eurostrings 2006. It’s a bit like the annual “Strings XXXX” conferences, although about half the size and organized just by European institutions that are part of the European Superstring Theory Network, which since last year has been funded by a grant from the EU. Part of the conference consists of a celebration of Michael Green’s 60th birthday.
Most of the talks are already available online. There’s not much new being reported, but the talks include a nice review talk on topological strings by Robbert Dijkgraaf. There’s another talk on recent work on topological strings by Erik Verlinde, and a week earlier there was a conference in Munich devoted to the subject.
Nathan Berkovits talked about work in progress with Nikita Nekrasov on multi-loop amplitudes using his pure spinor formalism. This subject still seems remarkably confused, with Berkovits explaining that they have found a problem they still don’t know how to resolve: their regularization causes amplitudes with genus larger than 6 to vanish, violating unitarity. For commentary on yet another new suggested formalism for defining superstring amplitudes due to Warren Siegel and Kiyoung Lee, see this posting by Lubos Motl.
As part of the Green birthday celebration, John Schwarz gave a talk on String Theory Books. He reminisced about the writing of the two-volume book with Green and Witten (his outline refers to a “removed chapter”, and “broken vow”, what are those?). Evidently the book was written in 9 months back in 1986, a truly heroic effort given its size. Last Monday, Schwarz finally finished up a new textbook on string theory, written with Katrin and Melanie Becker and entitled “String Theory and M-theory: A Modern Introduction”. They started writing back in February 2005, planning a 350 page book to be completed by the end of September, but ended up just last week completing a 729 page book. From the table of contents it looks like GSW abbreviated and updated, containg more modern material on branes, dualities, black hole entropy, flux compactifications and gauge/string dualities. It seems rather peculiar that flux compactifications and the landscape get a whole chapter, whereas AdS/CFT is dealt with in one section of one chapter. All in all, comparing the new book to the old one, twenty years later the subject has become a lot more complicated, a lot uglier, and the prospects for using it to predict anything about the standard model have vanished.
The Schwarz talk also has a link to a video of a Berlitz commercial featuring a German radio operator misunderstanding someone radioing in a distress call that they were sinking (the German hears this as “thinking”). I can’t at all figure out what this has to do with Schwarz’s talk. Is string theory making a distress call as it is sinking, but no one understands this?
Victor Rivelles attended, and has blog entries here, here and here. He reports on a talk by my fellow Princeton student Costas Bachas about using string theory techniques to solve capillarity and wetting problems, then comments that “If LHC provides no proof to string theory string theorists will not lose their job, they can just change to applied string theory!”