Sander Zwegers

On a completed generating function of locally harmonic Maass forms

While investigating the Doi-Naganuma lift, Zagier defined integral weight cusp forms

The Folsom-Ono grid contains only integers

f_D

On the modularity of certain functions from the Gromov–Witten theory of elliptic orbifolds

which are naturally defined in terms of binary quadratic forms of discriminant

MODULARITY OF THE CONCAVE COMPOSITION GENERATING FUNCTION

D

Rank-Crank type PDE’s and non-holomorphic Jacobi forms

. It was later determined by Kohnen and Zagier that the generating function for the

Nahm’s conjecture: asymptotic computations and counterexamples

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Rank-Crank type PDE's for higher level Appell functions

is a half-integral weight cusp form. A natural preimage of

On two fifth order mock theta functions

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On the Fourier coefficients of negative index meromorphic Jacobi forms

under a differential operator at the heart of the theory of harmonic weak Maass forms was determined by the first two authors and Kohnen. In this paper, we consider the modularity properties of the generating function of these preimages. We prove that although the generating function is not itelf modular, it can be naturally completed to obtain a half-integral weight modular object.

Mock maass theta functions

In a recent paper, Folsom and Ono constructed a canonical sequence of weight 1/2 mock theta functions and a canonical sequence of weight 3/2 weakly holomorphic modular forms, both using Poincare series. They show a remarkable symmetry in the coefficients of these functions and conjecture that all the coefficients are integers. We prove that this conjecture is true by giving an explicit construction for the weight 1/2 mock theta functions, using some results found by Guerzhoy.