QM Research Seminar: Nahm sums and 2d CFTs

Speaker: Kaiwen Sun (Uppsala University)


Abstract:

Nahm sums, also called fermionic sums are some special q-series which are closely related to 2d CFTs and SCFTs. For example, the renowned Rogers-Ramanujan functions are Nahm sums and also the characters of Lee-Yang model M(5,2). It is an open question to classify the Nahm sums with modularity. In rank 1, it was proved there only exist 7 Nahm sums. In rank 2 and 3, a conjectural list has been given by Don Zagier. I will discuss some recent progress on Nahm sums and generalized Nahm sums. This is based on a joint work with Haowu Wang.