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arXiv · 2103.06586

Exact-WKB, complete resurgent structure, and mixed anomaly in quantum mechanics on $S^1$

Naohisa Sueishi·Syo Kamata·Tatsuhiro Misumi·Mithat Ünsal
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Abstract

We investigate the exact-WKB analysis for quantum mechanics in a periodic potential, with $N $ minima on $S^{1}$. We describe the Stokes graphs of a general potential problem as a network of Airy-type or degenerate Weber-type building blocks, and provide a dictionary between the two. The two formulations are equivalent, but with their own pros and cons. Exact-WKB produces the quantization condition consistent with the known conjectures and mixed anomaly. The quantization condition for the case of $N$-minima on the circle factorizes over the Hilbert sub-spaces labeled by discrete theta angle (or Bloch momenta), and is consistent with 't Hooft anomaly for even $N$ and global inconsistency for odd $N$. By using Delabaere-Dillinger-Pham formula, we prove that the resurgent structure is closed in these Hilbert subspaces, built on discrete theta vacua, and by a transformation, this implies that fixed topological sectors (columns of resurgence triangle) are also closed under resurgence.

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Naohisa Sueishi, Syo Kamata, Tatsuhiro Misumi, Mithat Ünsal. 2021-03-11. Exact-WKB, complete resurgent structure, and mixed anomaly in quantum mechanics on $S^1$. https://doi.org/10.1007/jhep07(2021)096

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