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Related papers: Special codimension one loci in Hurwitz spaces

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We show that certain geometrically defined higher codimension cycles are extremal in the effective cone of the moduli space $\overline{\mathcal M}_{g,n}$ of stable genus $g$ curves with $n$ ordered marked points. In particular, we prove…

Algebraic Geometry · Mathematics 2017-05-17 Dawei Chen , Izzet Coskun

In this paper we study the rigidity problem for sub-static systems with possibly non-empty boundary. First, we get local and global splitting theorems by assuming the existence of suitable compact minimal hypersurfaces, complementing recent…

Differential Geometry · Mathematics 2026-05-28 Giulio Colombo , Allan Freitas , Luciano Mari , Marco Rigoli

We prove a special case of Erd\H{o}s' unit distance problem using a corollary of the subspace theorem bounding the number of solutions of linear equations from a multiplicative group. We restrict our attention to unit distances coming from…

Combinatorics · Mathematics 2012-11-30 Ryan Schwartz

Let $\mathcal{H}_{k,g}$ be the Hurwitz stack parametrizing degree $k$, genus $g$ covers of $\mathbb{P}^1$. We define the tautological ring of $\mathcal{H}_{k,g}$ and we show that all Chow classes, except possibly those supported on the…

Algebraic Geometry · Mathematics 2021-10-05 Samir Canning , Hannah Larson

Let $k$ be an algebraically closed field and let $b$ and $n$ be integers with $n\geq 3$ and $1\leq b \leq n-1.$ Consider the moduli space $X$ of hypersurfaces in $\mathbb{P}^n_k$ of fixed degree $l$ whose singular locus is at least…

Algebraic Geometry · Mathematics 2024-06-04 Kaloyan Slavov

Moduli space of genus zero stable maps to the projective three-space naturally carries a real structure such that the fixed locus is a moduli space for real rational spatial curves with real marked points. The latter is a normal projective…

Algebraic Geometry · Mathematics 2009-04-21 Nicolas Puignau

We show that the canonical bundle of the Hurwitz stack classifying covers of genus g>1 and degree k>2 of the projective line is big. We show that all coarse moduli spaces of trigonal curves of genus g>1 are of general type.

Algebraic Geometry · Mathematics 2023-12-11 Gavril Farkas , Scott Mullane

We extend the group theoretic construction of local models of Pappas and Zhu to the case of groups obtained by Weil restriction along a possibly wildly ramified extension. This completes the construction of local models for all reductive…

Number Theory · Mathematics 2019-02-20 Brandon Levin

A result of Belyi can be stated as follows. Every curve defined over a number field can be expressed as a cover of the projective line with branch locus contained in a rigid divisor. We define the notion of geometrically rigid divisors in…

Algebraic Geometry · Mathematics 2007-05-23 Kapil Hari Paranjape

Inside the moduli space of curves of genus three with one marked point, we consider the locus of hyperelliptic curves with a marked Weierstrass point, and the locus of non-hyperelliptic curves with a marked hyperflex. These loci have…

Algebraic Geometry · Mathematics 2016-02-26 Dawei Chen , Nicola Tarasca

We show that the conditions imposed on a second order linear differential equation with rational coefficients on the complex line by requiring it to have regular singularities with fixed exponents at the points of a finite set $P$ and…

Algebraic Geometry · Mathematics 2016-08-09 Szilard Szabo

In this paper we consider a canonical compactification of Hitchin's moduli space of stable Higgs bundles with fixed determinant of odd degree over a Riemann surface, producing a projective variety by gluing in a divisor at infinity. We give…

Algebraic Geometry · Mathematics 2007-05-23 Tamas Hausel

We study divisors in the blow-up of $\mathbb{P}^n$ at points in general position that are non-special with respect to the notion of linear speciality introduced in [5]. We describe the cohomology groups of their strict transforms via the…

Algebraic Geometry · Mathematics 2017-02-14 Olivia Dumitrescu , Elisa Postinghel

Let $f\colon C \rightarrow \mathbb{P}^1$ be a degree $k$ genus $g$ cover. The stratification of line bundles $L \in \mathrm{Pic}^d(C)$ by the splitting type of $f_*L$ is a refinement of the stratification by Brill-Noether loci $W^r_d(C)$.…

Algebraic Geometry · Mathematics 2020-10-16 Hannah K. Larson

In this paper we study the embedded topology of reducible plane curves having a smooth irreducible component. In previous studies, the relation between the topology and certain torsion classes in the Picard group of degree zero of the…

Algebraic Geometry · Mathematics 2022-06-01 E. Artal Bartolo , S. Bannai , T. Shirane , H. Tokunaga

We consider a singular holomorphic foliation $\uF$ defined near a compact curve $\uC$ of a complex surface. Under some hypothesis on $(\uF,\uC)$ we prove that there exists a system of tubular neighborhoods $U$ of a curve $\underline{\mc D}$…

Dynamical Systems · Mathematics 2012-06-12 David Marín , Jean-François Mattei

The \it critical filtration \rm of a Hurwitz space stratifies it according to the number of the critical values; the \it Belyi pairs \rm (three critical values) are considered as the 0-dimensional strata of these filtrations. The…

Algebraic Geometry · Mathematics 2019-02-07 George Shabat

This paper presents three new families of fractional Sobolev spaces and their accompanying theory in one-dimension. The new construction and theory are based on a newly developed notion of weak fractional derivatives, which are natural…

Functional Analysis · Mathematics 2020-07-21 Xiaobing Feng , Mitchell Sutton

This paper reviews known results on the rigid isotopy classification of plane curves of degree $m\leq6$ and curves of small degrees on quadrics. The paper's study completes the rigid isotopy classification of nonsingular real algebraic…

Algebraic Geometry · Mathematics 2025-10-02 Victor Ivanovich Zvonilov

While there is much work and many conjectures surrounding the intersection theory of the moduli space of curves, relatively little is known about the intersection theory of the Hurwitz space $\mathcal{H}_{k, g}$ parametrizing smooth degree…

Algebraic Geometry · Mathematics 2021-10-05 Samir Canning , Hannah Larson