On framed simple purely real Hurwitz numbers

M. E. Kazarian ; S. K. Lando ; S. M. Natanzon

Izvestiya. Mathematics , Tome 85 (2021) no. 4, pp. 681-704.

Résumé

We study real Hurwitz numbers enumerating real meromorphic functions of a special kind, referred to as framed purely real functions. We deduce partial differential equations of cut-and-join type for the generating functions for these numbers. We also construct a topological field theory for them.

Détail

Keywords: simple Hurwitz number, real algebraic curve, real meromorphic function, real simple Hurwitz number, cut-and-join equation.

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