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arXiv · 1608.08554

On the residue of Eisenstein classes of Siegel varieties

Francesco Lemma
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Abstract

Eisenstein classes of Siegel varieties are motivic cohomology classes defined as pull-backs by torsion sections of the polylogarithm prosheaf on the universal abelian scheme. By reduction to the Hilbert-Blumenthal case, we prove that the Betti realization of these classes on Siegel varieties of arbitrary genus have non-trivial residue on zero dimensional strata of the Baily-Borel compactification. A direct corollary is the non-vanishing of a higher regulator map.

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Francesco Lemma. 2016-08-29. On the residue of Eisenstein classes of Siegel varieties. https://arxiv.org/abs/1608.08554

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