10 citations · 25 across the 7 of their papers we have counts for
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Indefinite Theta Series on Cones
Martin Westerholt-Raum
We show that indefinite theta series on cones converge and provide an explicit modular completion. Our completion rests on a convolution of the Gaussian with a piecewise constant f…
Almost holomorphic Poincare series corresponding to products of harmonic Siegel-Maass forms
K. Bringmann, O. K. Richter, M. Westerholt-Raum
We investigate Poincaré series, where we average products of terms of Fourier series of real-analytic Siegel modular forms. There are some (trivial) special cases for which the pro…
Harmonic Weak Siegel Maaß Forms I
Martin Westerholt-Raum
Given a non-holomorphic Saito-Kurokawa lift we construct a preimage under the vector-valued lowering operator. In analogy with the case of harmonic weak elliptic Maaß forms, this p…
Sturm Bounds for Siegel Modular Forms
Olav K. Richter, Martin Westerholt-Raum
We establish Sturm bounds for degree g Siegel modular forms modulo a prime p, which are vital for explicit computations. Our inductive proof exploits Fourier-Jacobi expansions of S…
Products of Vector Valued Eisenstein Series
Martin Westerholt-Raum
We prove that products of at most two vector valued Eisenstein series that originate in level 1 span all spaces of cusp forms for congruence subgroups. This can be viewed as an ana…
Kudla's Modularity Conjecture and Formal Fourier-Jacobi Series
Jan Hendrik Bruinier, Martin Westerholt-Raum
We prove modularity of formal series of Jacobi forms that satisfy a natural symmetry condition. They are formal analogues of Fourier-Jacobi expansions of Siegel modular forms. From…
Formal Fourier Jacobi Expansions and Special Cycles of Codimension 2
Martin Raum
We prove that formal Fourier Jacobi expansions of degree 2 are Siegel modular forms. As a corollary, we deduce modularity of the generating function of special cycles of codimensio…
H-Harmonic Maass-Jacobi Forms of Degree 1: The Analytic Theory of Some Indefinite Theta Series
Martin Westerholt-Raum
It was shown in previous work that the one-variable -function defined by Zwegers (and Zagier) and his indefinite theta series attached to lattices of signature $(r\!+\!1…