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arXiv · 1303.5246

On ratios of Petersson norms for Yoshida lifts

Abhishek Saha
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Abstract

We prove an algebraicity property for a certain ratio of Petersson norms associated to a Siegel cusp form of degree 2 (and arbitrary level) whose adelization generates a weak endoscopic lift. As a preparation for this, we explicate various features of the correspondence between scalar valued Siegel cusp forms of degree n and automorphic representations on GSp_{2n}.

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Abhishek Saha. 2013-03-21. On ratios of Petersson norms for Yoshida lifts. https://arxiv.org/abs/1303.5246

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