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arXiv · 2103.07956

Arthur's multiplicity formula for even orthogonal and unitary groups

Rui Chen·Jialiang Zou
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Abstract

Let G be an even orthogonal or unitary group over a number field. Based on the same observation used in arXiv:1705.10106, we prove the Arthur's multiplicity formula for the generic part of the automorphic discrete spectrum of G by using the theta lift. We also consider a class of non-generic A-parameters and obtain a multiplicity formula in this case. In particular, we obtain a description of the full automorphic discrete spectrum of even orthogonal or unitary groups with Witt index less or equal to one.

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Rui Chen, Jialiang Zou. 2021-03-14. Arthur's multiplicity formula for even orthogonal and unitary groups. https://arxiv.org/abs/2103.07956

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