English
Related papers

Related papers: Vanishing thetanulls and hyperelliptic curves

200 papers

A lot is known about the moduli space of parabolic bundles over curves of genus $g\geq 2$, but the lower genus cases are notably different. The goal of this article is to study the geometry of the moduli space of semistable parabolic…

Algebraic Geometry · Mathematics 2026-05-26 Roberto Alvarenga , Inder Kaur , Frank Loray

We use hypersurfaces containing unexpected linear spaces to construct interesting vector bundles on complete intersection surfaces in projective space. We discover examples of moduli spaces of rank 2 stable bundles on surfaces of Picard…

Algebraic Geometry · Mathematics 2021-05-12 Izzet Coskun , Jack Huizenga , John Kopper

We study the locus of tropical hyperelliptic curves inside the moduli space of tropical curves of genus g. We define a harmonic morphism of metric graphs and prove that a metric graph is hyperelliptic if and only if it admits a harmonic…

Combinatorics · Mathematics 2011-10-04 Melody Chan

Given a lattice polygon $P$ with $g$ interior lattice points, we associate to it the moduli space of tropical curves of genus $g$ with Newton polygon $P$. We completely classify the possible dimensions such a moduli space can have. For…

Oort has conjectured that there do not exist Shimura curves contained generically in the Torelli locus of genus-$g$ curves when $g$ is large enough. In this paper we prove the Oort conjecture for Shimura curves of Mumford type and Shimura…

Algebraic Geometry · Mathematics 2014-08-19 Xin Lu , Kang Zuo

Let $A_g^S$ be the Satake compactification of the moduli space $A_g$ of principally polarized abelian $g$-folds and $M_g^S$ the closure of the image of the moduli space $M_g$ of genus $g$ curves in $A_g$ under the Jacobian morphism. Then…

Algebraic Geometry · Mathematics 2019-02-20 G. Codogni , N. I. Shepherd-Barron

We define and study the stack ${\mathcal U}^{ns,a}_{g,g}$ of (possibly singular) projective curves of arithmetic genus g with g smooth marked points forming an ample non-special divisor. We define an explicit closed embedding of a natural…

Algebraic Geometry · Mathematics 2017-10-18 Alexander Polishchuk

Let $C$ be a curve of genus two. We denote by $SU_C(3)$ the moduli space of semi-stable vector bundles of rank 3 and trivial determinant over $C$, and by $J^d$ the variety of line bundles of degree $d$ on $C$. In particular, $J^1$ has a…

Algebraic Geometry · Mathematics 2007-08-08 Quang Minh Nguyen

We establish a local model for the moduli space of holomorphic symplectic structures with logarithmic poles, near the locus of structures whose polar divisor is normal crossings. In contrast to the case without poles, the moduli space is…

Algebraic Geometry · Mathematics 2021-07-16 Mykola Matviichuk , Brent Pym , Travis Schedler

This paper deals with singularities of genus 2 curves on a general (d_1,d_2)-polarized abelian surface (S,L). In analogy with Chen's results concerning rational curves on K3 surfaces [Ch1,Ch2], it is natural to ask whether all such curves…

Algebraic Geometry · Mathematics 2020-07-08 Andreas Leopold Knutsen , Margherita Lelli-Chiesa

We introduce a new approach of computing the automorphism group and the field of moduli of points $\p=[C]$ in the moduli space of hyperelliptic curves $\H_g$. Further, we show that for every moduli point $\p \in \H_g(L)$ such that the…

Algebraic Geometry · Mathematics 2007-05-23 Tanush Shaska

In recent work by Arena, Canning, Clader, Haburcak, Li, Mok, and Tamborini it was proven that for infinitely many values of $g$ and $n$, there exist non-tautological algebraic cohomology classes on the moduli space $\mathcal{M}_{g,n}$ of…

Algebraic Geometry · Mathematics 2024-10-08 Dario Faro , Carolina Tamborini

Looijenga recently proved that the tautological ring of M_g vanishes in degree d>g-2 and is at most one-dimensional in degree g-2, generated by the class of the hyperelliptic locus. Here we show that K_{g-2} is non-zero on M_g. The proof…

Algebraic Geometry · Mathematics 2016-09-07 Carel F. Faber

We construct families of hyperelliptic curves over Q of arbitrary genus g with (at least) g integral elements in K_2. We also verify the Beilinson conjectures about K_2 numerically for several curves with g=2, 3, 4 and 5. The paper is…

Algebraic Geometry · Mathematics 2013-09-23 Tim Dokchitser , Rob de Jeu , Don Zagier

We describe a systematic way of constructing effective divisors on the moduli space of stable curves of genus g having exceptionally small slope. We prove that any divisor on \bar{M}_g consisting of curves failing a certain Green-Lazarsfeld…

Algebraic Geometry · Mathematics 2007-05-23 Gavril Farkas

In this paper we study asymptotic directions in the tangent bundle of the moduli space ${\mathcal M}_g$ of curves of genus $g$, namely those tangent directions that are annihilated by the second fundamental form of the Torelli map. We give…

Algebraic Geometry · Mathematics 2025-05-13 Elisabetta Colombo , Paola Frediani , Gian Pietro Pirola

The moduli space of smooth real plane quartic curves consists of six connected components. We prove that each of these components admits a real hyperbolic structure. These connected components correspond to the six real forms of a certain…

Algebraic Geometry · Mathematics 2021-12-14 Gert Heckman , Sander Rieken

Consider genus $g$ curves that admit degree $d$ covers to elliptic curves only branched at one point with a fixed ramification type. The locus of such covers forms a one parameter family $Y$ that naturally maps into the moduli space of…

Algebraic Geometry · Mathematics 2007-05-23 Dawei Chen

This paper shows that on the moduli space of semi-stable vector bundles of fixed rank and determinant (of any degree) on a smooth curve of genus at least two, the base locus of the generalized theta divisor is large provided the rank is…

Algebraic Geometry · Mathematics 2012-07-05 Sebastian Casalaina-Martin , Tawanda Gwena , Montserrat Teixidor i Bigas

We determine necessary conditions for ample divisors in arbitrary genus as well as for very ample divisors in genus 2 and 3. We also compute the intersection numbers $\lambda^9$ and $\lambda_{g-1}^3$ in genus 4. The latter number is…

alg-geom · Mathematics 2008-02-03 Carel Faber