Eigenform Product Identities For Hilbert Modular Forms

Kirti Joshi; Yichao Zhang

doi:10.1007/s00209-018-2214-y

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arXiv · 1505.01538

Eigenform Product Identities For Hilbert Modular Forms

Kirti Joshi·Yichao Zhang

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Abstract

We prove that amongst all real quadratic fields and all spaces of Hilbert modular forms of full level and of weight $2$ or greater, the product of two Hecke eigenforms is not a Hecke eigenform except for finitely many real quadratic fields and finitely many weights. We show that for $\mathbb Q(\sqrt 5)$ there are exactly two such identities.

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BibTeX RIS

Kirti Joshi, Yichao Zhang. 2015-05-06. Eigenform Product Identities For Hilbert Modular Forms. https://doi.org/10.1007/s00209-018-2214-y

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