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arXiv · 1612.07565

Mock Modular Index of M2-M5 Brane System

Tadashi Okazaki·Douglas J. Smith
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Abstract

We present BPS indices of the supergroup WZW models that live on intersecting M2-M5 brane systems. They can encode data of the stretched M2-branes between M5-branes and count the BPS states. They are generally expressed in terms of mock theta functions via the Kac-Wakimoto character formula of the affine Lie superalgebra. We give an explicit expression of the index for the $PSL(2|2)_{k=1}$ WZW model in terms of the second order multi-variable Appell-Lerch sum. It indicates that wall-crossing occurs in the BPS state counting due to the $C$-field on the M5-branes.

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Tadashi Okazaki, Douglas J. Smith. 2016-12-22. Mock Modular Index of M2-M5 Brane System. https://doi.org/10.1103/physrevd.96.026017

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