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Related papers: Tropical Hurwitz Numbers

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We compute the Picard groups with integral coefficients of the Hurwitz stacks parametrizing degree $4$ and $5$ covers of $\mathbb{P}^1$. As a consequence, we also determine the integral Picard groups of the Hurwitz stacks parametrizing…

Algebraic Geometry · Mathematics 2021-10-29 Samir Canning , Hannah Larson

For any natural number n, the Hurwitz graph $\mathcal{H}(S_n )$ has vertices corresponding to reduced words of the cycle $(1 . . . n)$ in terms of transpositions in $S_n$, and has edges corresponding to local shifts. This graph is known to…

Combinatorics · Mathematics 2015-08-12 Yuval Hovannes Khachatryan-Raziel

The Hurwitz form of a variety is the discriminant that characterizes linear spaces of complementary dimension which intersect the variety in fewer than degree many points. We study computational aspects of the Hurwitz form, relate this to…

Algebraic Geometry · Mathematics 2016-07-20 Bernd Sturmfels

In 2009 Kokotov, Korotkin and Zograf gave a formula for the class of the Hodge bundle on the Hurwitz space of admissible covers of genus g and degree d of the projective line. They gave an analytic proof of it. In this note we give an…

Algebraic Geometry · Mathematics 2011-07-15 Gerard van der Geer , Alexis Kouvidakis

In this survey article we give an overview of how noncongruence modular curves can be viewed as Hurwitz moduli spaces of covers of elliptic curves at most branched above the origin. We describe some natural questions that arise, and…

Number Theory · Mathematics 2025-10-15 William Y. Chen

Recently, Gunningham \cite{G} calculated all spin Hurwitz numbers in terms of combinatorics of Sergeev algebra. In this paper, we use a spin curve degeneration to obtain a recursion formula for degree three spin Hurwitz numbers.

Symplectic Geometry · Mathematics 2012-09-18 Junho Lee

We define the tropical Tevelev degrees, $\mathsf{Tev}_g^{trop}$, as the degree of a natural finite morphism between certain tropical moduli spaces, in analogy to the algebraic case. We develop an explicit combinatorial construction that…

Algebraic Geometry · Mathematics 2026-04-15 Renzo Cavalieri , Erin Dawson

We consider the enumeration of tropical curves in M\"obius strips for two different lattice structures and relate them to the enumeration of curves in two rational ruled surfaces over a complex elliptic curve. Using this correspondence, we…

Algebraic Geometry · Mathematics 2023-09-25 Thomas Blomme , Victoria Schleis

We prove a correspondence theorem for singular tropical surfaces in real three space, which recovers singular algebraic surfaces in an appropriate toric three-fold that tropicalize to a given singular tropical surface. Furthermore, we…

Algebraic Geometry · Mathematics 2018-08-24 Hannah Markwig , Thomas Markwig , Eugenii Shustin

Complex algebraic varieties become easy piecewise-linear objects after passing to the so-called tropical limit. Geometry of these limiting objects is known as tropical geometry. In this short survey we take a look at motivation and…

Algebraic Geometry · Mathematics 2011-11-18 I. Itenberg , G. Mikhalkin

We consider two applications of the strata of differentials of the second kind (all residues equal to zero) with fixed multiplicities of zeros and poles: Positivity: In genus $g=0$ we show any associated divisorial projection to…

Algebraic Geometry · Mathematics 2021-01-14 Scott Mullane

We study the geometry of varieties parametrizing degree d rational and elliptic curves in P^n intersecting fixed general linear spaces and tangent to a fixed hyperplane H with fixed multiplicities along fixed general linear subspaces of H.…

alg-geom · Mathematics 2008-02-03 Ravi Vakil

Edge-contraction operations form an effective tool in various graph enumeration problems, such as counting Grothendieck's dessins d'enfants and simple and double Hurwitz numbers. These counting problems can be solved by a mechanism known as…

Algebraic Geometry · Mathematics 2019-08-16 Olivia Dumitrescu , Motohico Mulase

This paper is the first part in a series of three papers devoted to the study of enumerative invariants of abelian surfaces through the tropical approach. In this paper, we consider the enumeration of genus $g$ curves of fixed degree…

Algebraic Geometry · Mathematics 2024-11-27 Thomas Blomme

We establish the equality of classical and tropical curve counts for elliptic curves on toric surfaces with fixed $j$-invariant, refining results of Mikhalkin and Nishinou--Siebert. As an application, we determine a formula for such counts…

Algebraic Geometry · Mathematics 2018-12-06 Yoav Len , Dhruv Ranganathan

We define tropical Psi-classes on the moduli space of rational tropical curves in R^2 and consider intersection products of Psi-classes and pull-backs of evaluations on this space. We show a certain WDVV equation which is sufficient to…

Algebraic Geometry · Mathematics 2009-11-29 Hannah Markwig , Johannes Rau

Double Hurwitz numbers count covers of the projective line by genus g curves with assigned ramification profiles over 0 and infinity, and simple ramification over a fixed branch divisor. Goulden, Jackson and Vakil have shown double Hurwitz…

Algebraic Geometry · Mathematics 2010-03-10 Renzo Cavalieri , Paul Johnson , Hannah Markwig

We propose a new, conjectural recursion solution for Hurwitz numbers at all genera. This conjecture is based on recent progress in solving type B topological string theory on the mirrors of toric Calabi-Yau manifolds, which we briefly…

Algebraic Geometry · Mathematics 2008-12-04 Vincent Bouchard , Marcos Marino

We present a simple and elementary procedure to sketch the tropical conic given by a degree--two homogeneous tropical polynomial. These conics are trees of a very particular kind. Given such a tree, we explain how to compute a defining…

Algebraic Geometry · Mathematics 2008-10-16 M. Ansola , M. J. de la Puente

We study the tropical lines contained in smooth tropical surfaces in R^3. On smooth tropical quadric surfaces we find two one-dimensional families of tropical lines, like in classical algebraic geometry. Unlike the classical case, however,…

Algebraic Geometry · Mathematics 2007-12-08 Magnus Dehli Vigeland