On a Theorem of Ihara

Arash Rastegar

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On a Theorem of Ihara

Arash Rastegar

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Abstract

Let $p$ be a prime number and let $n$ be a positive integer prime to $p$. By an Ihara result we mean existence of an injection with torsion-free cokernel from a full lattice in the space of $p$-old modular forms, into a full lattice in the space of all modular forms of level $np$. In this paper, we prove Ihara results for genus two Siegel modular forms, Siegel-Jacobi forms and Hilbert modular forms. We also propose a geometric formulation for the notion of $p$-old Siegel modular forms of genus two.

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Arash Rastegar. 2004-06-11. On a Theorem of Ihara. https://arxiv.org/abs/math/0406231

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