The theta characteristic of a branched covering

Alex Eskin, Andrei Okounkov, Rahul Pandharipande

Research output: Contribution to journalArticlepeer-review

28 Citations (Scopus)

Abstract

We give a group-theoretic description of the parity of a pull-back of a theta characteristic under a branched covering. It involves lifting monodromy of the covering to the semidirect product of the symmetric and Clifford groups, known as the Sergeev group. As an application, we enumerate torus coverings with respect to their ramification and parity and, in particular, show that the corresponding all-degree generating functions are quasimodular forms.

Original languageEnglish
Pages (from-to)873-888
Number of pages16
JournalAdvances in Mathematics
Volume217
Issue number3
DOIs
Publication statusPublished - 15 Feb 2008
Externally publishedYes

Keywords

  • Branched covering
  • Theta characteristic

Fingerprint

Dive into the research topics of 'The theta characteristic of a branched covering'. Together they form a unique fingerprint.

Cite this