Joint Theory Seminar: Can Kozcaz

Title: String Theoretic Approach to qq-characters

Abstract:
Frenkel and Reshetikhin introduced the q-characters to study finite dimensional representations of quantized universal enveloping algebras, which can be regarded as the quantization of the usual characters. Nekrasov gave a gauge theoretic interpretation to further quantize the q-characters in terms of operator insertions, and called them qq-characters. In this talk, I will first present a string theory construction for the qq-characters for any simple Lie group. Following this, I will focus on a new approach to study the qq-character for any symmetric representations of A-type groups using the refined topological vertex.