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Related papers: Compactifications of Hurwitz spaces

200 papers

We construct a good compactification of the variety of irreducible projective plane curves of degree n with d nodes and no other singularities.

alg-geom · Mathematics 2008-02-03 Robert Treger

In 1891, Hurwitz introduced the enumeration of genus $g$, degree $d$, branched covers of the Riemann sphere with simple ramification over prescribed points and no branching elsewhere. He showed that for fixed degree $d$, the enumeration…

Combinatorics · Mathematics 2024-09-11 Norman Do , Jian He , Heath Robertson

We discuss the `hd-compactification' of a semi-simple Lie group to a manifold with corners; it is the real analog of the wonderful compactification of deConcini and Procesi. There is a 1-1 correspondence between the boundary faces of the…

Differential Geometry · Mathematics 2019-10-08 Pierre Albin , Panagiotis Dimakis , Richard Melrose , David Vogan

We construct a compactification M_d of the moduli space of plane curves of degree d. We regard a plane curve C as a surface-divisor pair (P^2,C) and define M_d as a moduli space of pairs (X,D) where X is a degeneration of the plane. We show…

Algebraic Geometry · Mathematics 2010-03-16 Paul Hacking

We give an introduction to the compactification of the moduli space of surfaces of general type introduced by Koll\'ar and Shepherd-Barron and generalized to the case of surfaces with a divisor by Alexeev. The construction is an application…

Algebraic Geometry · Mathematics 2011-07-15 Paul Hacking

The complement of an arrangement of hyperplanes in $\mathbb C^n$ has a natural bordification to a manifold with corners formed by removing (or "blowing up") tubular neighborhoods of the hyperplanes and certain of their intersections. When…

Geometric Topology · Mathematics 2021-04-07 Michael W. Davis , Jingyin Huang

We construct a combinatorial moduli space closely related to the KSV-compactification of the moduli space of bordered marked Riemann surfaces. The open part arises from symmetric metric ribbon graphs. The compactification is obtained by…

Geometric Topology · Mathematics 2023-10-03 Ralph Kaufmann , Javier Zúñiga

We resolve pathological wall-crossing phenomena for moduli spaces of sheaves on higher-dimensional base manifolds. This is achieved by considering slope-semistability with respect to movable curves rather than divisors. Moreover, given a…

Algebraic Geometry · Mathematics 2018-04-19 Daniel Greb , Matei Toma

We study the moduli space ${V}_4\mathcal{M}_{g}$ of Klein four covers of genus $g$ curves and its natural compactification. This requires the construction of a related space which has a choice of basis for the Klein four group. This space…

Algebraic Geometry · Mathematics 2014-07-15 Charles Siegel

The minimal model program suggests a compactification of the moduli space of hyperplane arrangements which is a moduli space of stable pairs. Here, a stable pair consists of a scheme X which is a degeneration of projective space and a…

Algebraic Geometry · Mathematics 2007-05-23 Paul Hacking

We introduce moduli spaces of quasi-admissible hyperelliptic covers with at worst A and D singularities. The stability conditions for these moduli spaces depend on two parameters describing allowable singularities. By varying these…

Algebraic Geometry · Mathematics 2010-12-03 Maksym Fedorchuk

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

We classify the possible closures of leaves of the isoperiodic foliation (sometimes called absolute period foliation) defined on the Hodge bundle, i.e. the moduli space of abelian differentials over genus $g\geq 2$ smooth curves, and prove…

Algebraic Geometry · Mathematics 2025-08-04 Gabriel Calsamiglia , Bertrand Deroin , Stefano Francaviglia

We investigate low degree rational cohomology groups of smooth compactifications of moduli spaces of curves with level structures. In particular, we determine $H^k(\sgbar, \Q)$ for $g \ge 2$ and $k \le 3$, where $\sgbar$ denotes the moduli…

Algebraic Geometry · Mathematics 2011-02-07 Gilberto Bini , Claudio Fontanari

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

We construct a smooth Deligne-Mumford compactification for the moduli space of curves with an m-tuple of spin structures using line bundles on quasi-stable curves as limiting objects, as opposed to line bundles on stacky curves. For all m,…

Algebraic Geometry · Mathematics 2023-07-18 Emre Can Sertöz

We construct a modular desingularisation of $\overline{\mathcal{M}}_{2,n}(\mathbb{P}^r,d)^{\text{main}}$. The geometry of Gorenstein singularities of genus two leads us to consider maps from prestable admissible covers: with this enhanced…

Algebraic Geometry · Mathematics 2023-06-14 Luca Battistella , Francesca Carocci

We investigate two families of divisors which we expect to play a distinguished role in the global geometry of Hurwitz space. In particular, we show that they are extremal and rigid in the small degree regime $d \leq 5$. We further show…

Algebraic Geometry · Mathematics 2015-08-26 Anand Patel

Hurwitz numbers count genus g, degree d covers of the projective line with fixed branch locus. This equals the degree of a natural branch map defined on the Hurwitz space. In tropical geometry, algebraic curves are replaced by certain…

Algebraic Geometry · Mathematics 2010-07-19 Renzo Cavalieri , Paul Johnson , Hannah Markwig

We prove that the moduli spaces A_3(D) of polarized abelian threefolds with polarizations of types D=(1,1,2), (1,2,2), (1,1,3) or (1,3,3) are unirational. The result is based on the study of families of simple coverings of elliptic curves…

Algebraic Geometry · Mathematics 2007-05-23 Vassil Kanev