Yves Benoist - Convolution and Square on Abelian Groups @IhesFr

Uploaded September 2025 | Updated September 2026, 2 weeks ago

We will construct functions on finite abelian groups whose convolution square is proportional to their square. For that, we will interpret the abelian group as a subgroup of an abelian variety with complex multiplication, and use the modularity properties of their theta functions.

Yves Benoist (CNRS, Université Paris-Saclay)

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Yves Benoist - Convolution and Square on Abelian Groups

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