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Related papers: Chamber Structure of Double Hurwitz numbers

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Hurwitz numbers count branched covers of the Riemann sphere with specified ramification, or equivalently, transitive permutation factorizations in the symmetric group with specified cycle types. Monotone Hurwitz numbers count a restricted…

Combinatorics · Mathematics 2012-10-15 I. P. Goulden , Mathieu Guay-Paquet , Jonathan Novak

Hurwitz numbers count covers of curves satisfying fixed ramification data. Via monodromy representation, this counting problem can be transformed to a problem of counting factorizations in the symmetric group. This and other beautiful…

Combinatorics · Mathematics 2023-12-07 Marvin Anas Hahn , Hannah Markwig

In this paper, we collect a number of facts about double Hurwitz numbers, where the simple branch points are replaced by their more general analogues --- completed (r+1)-cycles. In particular, we give a geometric interpretation of these…

Combinatorics · Mathematics 2014-02-26 S. Shadrin , L. Spitz , D. Zvonkine

This survey grew out of notes accompanying a cycle of lectures at the workshop Modern Trends in Gromov-Witten Theory, in Hannover. The lectures are devoted to interactions between Hurwitz theory and Gromov-Witten theory, with a particular…

Algebraic Geometry · Mathematics 2016-04-14 Renzo Cavalieri

We define the dimension 2g-1 Faber-Hurwitz Chow/homology classes on the moduli space of curves, parametrizing curves expressible as branched covers of P^1 with given ramification over infinity and sufficiently many fixed ramification points…

Algebraic Geometry · Mathematics 2007-05-23 Ian P. Goulden , David M. Jackson , Ravi Vakil

Hurwitz theory provides a large variety of enumerative problems related to algebraic geometry, mathematical physics, and combinatorics. We give a general framework to approach the large genus asymptotics of Hurwitz theory using only…

Algebraic Geometry · Mathematics 2026-04-15 Davide Accadia , Danilo Lewański , Giulio Ruzza

Double Hurwitz numbers enumerating weighted $n$-sheeted branched coverings of the Riemann sphere or, equivalently, weighted paths in the Cayley graph of $S_n$ generated by transpositions are determined by an associated weight generating…

Mathematical Physics · Physics 2018-06-26 Mathieu Guay-Paquet , J. Harnad

The Hurwitz space is a compactification of the space of rational functions of a given degree. We study the intersection of various strata of this space with its boundary. A study of the cohomology ring of the Hurwitz space then allows us to…

Algebraic Geometry · Mathematics 2007-05-23 Dimitri Zvonkine

Motivated by results for the HCIZ integral in Part I of this paper, we study the structure of monotone Hurwitz numbers, which are a desymmetrized version of classical Hurwitz numbers. We prove a number of results for monotone Hurwitz…

Combinatorics · Mathematics 2011-07-07 Ian P. Goulden , Mathieu Guay-Paquet , Jonathan Novak

We study the quantum Witten-Kontsevich series introduced by Buryak, Dubrovin, Gu\'er\'e and Rossi in \cite{buryak2016integrable} as the logarithm of a quantum tau function for the quantum KdV hierarchy. This series depends on a genus…

Mathematical Physics · Physics 2022-11-09 Xavier Blot

In the Hurwitz space of rational functions on CP^1 with poles of given orders, we study the loci of multisingularities, that is, the loci of functions with a given ramification profile over 0. We prove a recursion relation on the Poincare…

Algebraic Geometry · Mathematics 2019-08-02 Maxim Kazarian , Sergei Lando , Dimitri Zvonkine

Simple Hurwitz numbers enumerate branched morphisms between Riemann surfaces with fixed ramification data. In recent years, several variants of this notion for genus $0$ base curves have appeared in the literature. Among them are so-called…

Algebraic Geometry · Mathematics 2022-11-02 Marvin Anas Hahn , Jan-Willem M. van Ittersum , Felix Leid

This article is an extended version of preprint math.AG/9902104. We find an explicit formula for the number of topologically different ramified coverings of a sphere by a genus g surface with only one complicated branching point in terms of…

Algebraic Geometry · Mathematics 2009-10-31 T. Ekedahl , S. Lando , M. Shapiro , A. Vainshtein

We define a new class of enumerative invariants called $k$-leaky double Hurwitz descendants, generalizing both descendant integrals of double ramification cycles and the $k$-leaky double Hurwitz numbers introduced in previous work of…

Algebraic Geometry · Mathematics 2024-04-17 Renzo Cavalieri , Hannah Markwig , Johannes Schmitt

Going beyond the studies of single and double Hurwitz numbers, we report some progress towards studying Hurwitz numbers which correspond to ramified coverings of the Riemann sphere involving three nonsimple branch points. We first prove a…

Combinatorics · Mathematics 2024-07-24 Ricky Xiao-Feng Chen

Hurwitz numbers count branched covers of the Riemann sphere with specified ramification data, or equivalently, transitive permutation factorizations in the symmetric group with specified cycle types. Monotone Hurwitz numbers count a…

Combinatorics · Mathematics 2019-08-15 I. P. Goulden , Mathieu Guay-Paquet , Jonathan Novak

We define the double Gromov-Witten invariants of Hirzebruch surfaces in analogy with double Hurwitz numbers, and we prove that they satisfy a piecewise polynomiality property analogous to their 1-dimensional counterpart. Furthermore we show…

Algebraic Geometry · Mathematics 2015-12-02 Federico Ardila , Erwan Brugalle

We show that the signed counts of normalized real polynomials, as defined by Itenberg and Zvonkine, provide the signed counts of genus zero real ramified coverings of the Riemann sphere with a point of total ramification and several other…

Algebraic Geometry · Mathematics 2025-06-23 Yanqiao Ding

We are building a theory of simple Hurwitz numbers for the reflection groups B and D parallel to the classical theory for the symmetric group. We also study analogs of the cut-and-join operators. An algebraic description of Hurwitz numbers…

Combinatorics · Mathematics 2023-03-20 Raphaël Fesler

Inspired by piecewise polynomiality results of double Hurwitz numbers, Ardila and Brugall\'e introduced an enumerative problem which they call double Gromov--Witten invariants of Hirzebruch surfaces. These invariants serve as a…

Algebraic Geometry · Mathematics 2025-08-22 Marvin Anas Hahn , Vincenzo Reda