One of string theory’s early pioneers, Michael Green, is currently visiting the Niels Bohr Institute as part of a program by the Simons Foundation. The program includes a series of conferences. This week we are having the first such conference, on Hadronic Strings and Large-N Field Theory.
The bulk of the conference focused on new progress on an old subject, using string theory to model the behavior of quarks and gluons. There were a variety of approaches on offer, some focused on particular approximations and others attempting to construct broader, “phenomenological” models.
The other talks came from a variety of subjects, loosely tied together by the topic of “large N field theories”. “N” here is the number of colors: while the real world has three “colors” of quarks, you can imagine a world with more. This leads to simpler calculations, and often to connections with string theory. Some talks deal with attempts to “solve” certain large-N theories exactly. Others ranged farther afield, even to discussions of colliding black holes.
4 gravitons 
Can you tell us more about this: “Some talks deal with attempts to “solve” certain large-N theories exactly”
Author names, papers, slides, andan your opinion on this. Please, at least I will be very gratefull 🙂 🙂
I love your blog, you write in a intense and joyfull way.
LikeLike
The main thing I had in mind there was Amit Sever’s talk, about this paper, and more generally work on integrability in planar N=4 super Yang-Mills (here’s an older review article on the topic, at the moment I can’t find a more recent one). Unfortunately talks weren’t recorded for this conference so I don’t have slides to link, you can probably find talks by Amit in the past about it though.
Amit’s recent work has been on the leading corrections to the large-N limit. It’s cool that it’s possible to make progress on this, but I’m a bit frustrated that his approach still leaves some loop momentum integrals to do, since that makes it hard to compare with other approaches, or to use in the kind of “bootstrap” work I do.
Not sure if that was helpful since I wasn’t sure of your background, let me know if you’d like me to explain anything better!
LikeLike
It was usefull
LikeLike
If the N in “N=4 super Yang-Mills” dimensions or colors?
LikeLike
Neither. It’s the number of supersymmetries.
It’s less confusing in a paper where we use a fancy font for the N in N=4 and a more normal font for the N in “large N”, but it still trips people up sometimes!
LikeLike