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arXiv · 2503.20375

Alg{\`e}bres diff{\'e}rentielles de formes quasi-Jacobi d'indice nul

François Dumas·François Martin·Emmanuel Royer
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Abstract

The notion of double depth associated with quasi-Jacobi forms allows distinguishing,within the algebra of quasi-Jacobi singular forms of index zero, certain significant subalgebras (modular-type forms, elliptic-type forms, Jacobi forms). We study the stability of these subalgebras under the derivations of the algebra of quasi-Jacobi singular forms of index zero and through certain sequences of bidifferential operators constituting analogs of Rankin-Cohen brackets or transvectants.

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François Dumas, François Martin, Emmanuel Royer. 2025-03-26. Alg{\`e}bres diff{\'e}rentielles de formes quasi-Jacobi d'indice nul. https://arxiv.org/abs/2503.20375

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