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arXiv · 2012.07573

Intersection numbers on $\overline {\mathcal M}_{g,n}$ and BKP hierarchy

Alexander Alexandrov
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Abstract

In their recent inspiring paper Mironov and Morozov claim a surprisingly simple expansion formula for the Kontsevich-Witten tau-function in terms of the Schur Q-functions. Here we provide a similar conjecture for the Br\'ezin-Gross-Witten tau-function. Moreover, we identify both tau-functions of the KdV hierarchy, which describe intersection numbers on the moduli spaces of punctured Riemann surfaces, with the hypergeometric solutions of the BKP hierarchy.

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Alexander Alexandrov. 2020-12-14. Intersection numbers on $\overline {\mathcal M}_{g,n}$ and BKP hierarchy. https://arxiv.org/abs/2012.07573

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