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arXiv · 2103.04561

Decompositions of index one Jacobi forms into $N=4$ characters and formulas for mock modular forms

Matthew Krauel·Geoffrey Mason·Michael Tuite·Gaywalee Yamskulna
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Abstract

It is shown that every weak Jacobi form of weight zero and index one on a congruence subgroup of the full Jacobi group can be decomposed into $N=4$ superconformal characters. Additionally, a simple expression for the mock modular form determining the superconformal character coefficients is obtained, as well as a universal completion structure. Along the way, a useful vector-valued mock modular form is also found and studied. These results are applied to analyze some Jacobi trace functions associated to super vertex operator algebras and a distinguished sector.

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Matthew Krauel, Geoffrey Mason, Michael Tuite, Gaywalee Yamskulna. 2021-03-08. Decompositions of index one Jacobi forms into $N=4$ characters and formulas for mock modular forms. https://arxiv.org/abs/2103.04561

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