Differential operators on Hermitian modular forms on $\mathrm{U}(n, n)$

Nobuki Takeda

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arXiv · 2506.18236

Differential operators on Hermitian modular forms on $\mathrm{U}(n, n)$

Nobuki Takeda

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Abstract

We construct explicit differential operators on hermitian modular forms, extending methods developed for Siegel modular forms. These differential operators are closely related to the two-variable spherical pluriharmonic polynomials. We construct explicit bases for the space of such polynomials and use them to build concrete operators. As an application, we derive an exact pullback formula for hermitian Eisenstein series.

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Nobuki Takeda. 2025-06-23. Differential operators on Hermitian modular forms on $\mathrm{U}(n, n)$. https://arxiv.org/abs/2506.18236

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