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arXiv · 1809.10668

Pullbacks of universal Brill-Noether classes via Abel-Jacobi morphisms

Nicola Pagani·Andrea T. Ricolfi·Jason van Zelm
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Abstract

Following Mumford and Chiodo, we compute the Chern character of the derived pushforward $\textrm{ch} (R^\bullet\pi_\ast\mathscr{O}(\mathsf{D}))$, for $\mathsf D$ an arbitrary element of the Picard group of the universal curve over the moduli stack of stable marked curves. This allows us to express the pullback of universal Brill-Noether classes via Abel-Jacobi sections to the compactified universal Jacobians, for all compactifications such that the section is a well-defined morphism.

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Nicola Pagani, Andrea T. Ricolfi, Jason van Zelm. 2018-09-27. Pullbacks of universal Brill-Noether classes via Abel-Jacobi morphisms. https://doi.org/10.1002/mana.201800422

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