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arXiv · 2010.08736

Proofs of Ibukiyama's conjectures on Siegel modular forms of half-integral weight and of degree 2

Hiroshi Ishimoto
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Abstract

We prove Ibukiyama's conjectures on Siegel modular forms of half-integral weight and of degree 2 by using Arthur's multiplicity formula on the split odd special orthogonal group $\SO_5$ and Gan-Ichino's multiplicity formula on the metaplectic group $\Mp_4$. In the proof, the representation theory of the Jacobi groups also plays an important role.

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Hiroshi Ishimoto. 2020-10-17. Proofs of Ibukiyama's conjectures on Siegel modular forms of half-integral weight and of degree 2. https://arxiv.org/abs/2010.08736

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