Rank two false theta functions and Jacobi forms of negative definite matrix index

Kathrin Bringmann; Jonas Kaszian; Antun Milas; Sander Zwegers

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arXiv · 1902.10554

Rank two false theta functions and Jacobi forms of negative definite matrix index

Kathrin Bringmann·Jonas Kaszian·Antun Milas·Sander Zwegers

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Abstract

In this paper, we study a family of rank two false theta series associated to the root lattice of type $A_2$. We show that these functions appear as Fourier coefficients of a meromorphic Jacobi form of negative definite matrix index. Hypergeometric $q$-series identities are also obtained.

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BibTeX RIS

Kathrin Bringmann, Jonas Kaszian, Antun Milas, Sander Zwegers. 2019-02-27. Rank two false theta functions and Jacobi forms of negative definite matrix index. https://arxiv.org/abs/1902.10554

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