Topological recursion and uncoupled BPS structures for hypergeometric spectral curves
I'll describe joint work with K. Iwaki relating the computation of free energies in the theory of topological recursion (TR) to the counting of "BPS states" (degenerate spectral networks) in 4d N=2 QFTs, in the case where the latter structure is "uncoupled". In particular, I'll describe a simple formula expressing the TR free energies as a sum over BPS states for the relevant quadratic differential and outline the proof, for examples arising from the hypergeometric spectral curve and its confluent degenerations. I will explain how this picture ought to generalize; if time permits, how Bridgeland's tau-function appears after taking the Borel sum. Based on arXiv:2010.05596.