English

$k$-leaky double Hurwitz descendants

Algebraic Geometry 2024-04-17 v1 Combinatorics

Abstract

We define a new class of enumerative invariants called kk-leaky double Hurwitz descendants, generalizing both descendant integrals of double ramification cycles and the kk-leaky double Hurwitz numbers introduced in previous work of Cavalieri, Markwig and Ranganathan. These numbers are defined as intersection numbers of the logarithmic DR cycle against ψ\psi-classes and logarithmic classes coming from piecewise polynomials encoding fixed branch point conditions. We give a tropical graph sum formula for these new invariants, allowing us to show their piecewise polynomiality and a wall-crossing formula in genus zero. We also prove that in genus zero the invariants are always non-negative and give a complete classification of the cases where they vanish.

Keywords

Cite

@article{arxiv.2404.10168,
  title  = {$k$-leaky double Hurwitz descendants},
  author = {Renzo Cavalieri and Hannah Markwig and Johannes Schmitt},
  journal= {arXiv preprint arXiv:2404.10168},
  year   = {2024}
}
R2 v1 2026-06-28T15:55:12.813Z