English
Related papers

Related papers: On the complexity of Chow and Hurwitz forms

200 papers

This is a book about computational aspects of modular forms and the Galois representations attached to them. The main result is the following: Galois representations over finite fields attached to modular forms of level one can, in almost…

Number Theory · Mathematics 2010-03-23 Bas Edixhoven , Jean-Marc Couveignes , Robin de Jong , Franz Merkl , Johan Bosman

We compute the degree of Hurwitz-Hodge classes $\lambda_1^e$ on one dimensional moduli spaces of cyclic admissible covers of the projective line. We also compute the degree of the the first Chern class of the Hodge bundle $\lambda_1$ for…

Algebraic Geometry · Mathematics 2021-12-30 Renzo Cavalieri , Bryson Owens , Seamus Somerstep

In an earlier paper we showed that we can improve results by Emmy Noether and Alexander Ostrowski concerning the reducibility modulo p of absolutely irreducible polynomials with integer coefficients by giving the problem a geometric turn…

Number Theory · Mathematics 2007-05-23 Reinie Erne

The main goal of the paper is to present a new approach via Hurwitz numbers to Kontsevich's combinatorial/matrix model for the intersection theory of the moduli space of curves. A secondary goal is to present an exposition of the circle of…

Algebraic Geometry · Mathematics 2007-05-23 Andrei Okounkov , Rahul Pandharipande

Let X be a smooth projective toric surface, and H^d(X) the Hilbert scheme parametrising the length d zero-dimensional subschemes of X. We compute the rational Chow ring A^*(H^d(X))\_Q. More precisely, if T is the two-dimensional torus…

Algebraic Geometry · Mathematics 2007-05-23 Laurent Evain

For a smooth complex projective variety X defined over a number field, we have filtrations on the Chow groups depending of the choice of realizations. If the realization consists of mixed Hodge structure without any additional structure, we…

Algebraic Geometry · Mathematics 2007-05-23 Morihiko Saito

The classical Chow form encodes any projective variety by one equation. We here introduce the Chow-Lam form for subvarieties of a Grassmannian. By evaluating the Chow-Lam form at twistor coordinates, we obtain universal projection formulas.…

Algebraic Geometry · Mathematics 2025-02-20 Elizabeth Pratt , Bernd Sturmfels

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

We consider free algebraic actions of the additive group of complex numbers on a complex vector space X embedded in the complex projective space. We find an explicit formula for the map p that assigns to a generic point x in X the Chow…

Algebraic Geometry · Mathematics 2011-09-20 Annett Puettmann

We determine that the Chow ring (with ${\bf Q}$-coefficients) of the Hurwitz space parametrizing degree three covers of ${\bf P}^{1}$ is tautological. We also compute the rational Picard groups of auxiliary spaces of degree three maps with…

Algebraic Geometry · Mathematics 2024-05-28 Anand Patel , Ravi Vakil

We study the Hilbert series of four objects arising in the Chow-theoretic and Kazhdan-Lusztig framework of matroids. These are, respectively, the Hilbert series of the Chow ring, the augmented Chow ring, the intersection cohomology module,…

Combinatorics · Mathematics 2024-06-05 Luis Ferroni , Jacob P. Matherne , Matthew Stevens , Lorenzo Vecchi

We use algebraic methods to compute the simple Hurwitz numbers for arbitrary source and target Riemann surfaces. For an elliptic curve target, we reproduce the results previously obtained by string theorists. Motivated by the Gromov-Witten…

High Energy Physics - Theory · Physics 2015-06-25 Stefano Monni , Jun S. Song , Yun S. Song

We obtain a formula for the generating series of (the push-forward under the Hilbert-Chow morphism of) the Hirzebruch homology characteristic classes of the Hilbert schemes of points for a smooth quasi-projective variety of arbitrary pure…

Algebraic Geometry · Mathematics 2014-11-11 Sylvain Cappell , Laurentiu Maxim , Toru Ohmoto , Joerg Schuermann , Shoji Yokura

We construct an isomorphism of graded Frobenius algebras between the orbifold Chow ring of weighted projective spaces and graded algebras of groups of roots of the unity.

Algebraic Geometry · Mathematics 2007-10-01 Samuel Boissiere , Etienne Mann , Fabio Perroni

This paper studies the canonical Chow quotient of a smooth projective variety by a reductive algebraic group. The main purpose is to give some topological interpretations and characterization of Chow quotient which have the advantage to be…

Algebraic Geometry · Mathematics 2007-05-23 Yi Hu

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

In this PhD thesis, we give a new geometric approach to higher Teichm\"uller theory. In particular we construct a geometric structure on surfaces, generalizing the complex structure, and we explore its link to Hitchin components. The…

Differential Geometry · Mathematics 2020-07-02 Alexander Thomas

We compute the Chow ring of an arbitrary heavy/light Hassett space $\bar{M}_{0, w}$. These spaces are moduli spaces of weighted pointed stable rational curves, where the associated weight vector $w$ consists of only heavy and light weights.…

Algebraic Geometry · Mathematics 2020-10-28 Siddarth Kannan , Dagan Karp , Shiyue Li

The study of the moduli of covers of the projective line leads to the theory of Hurwitz varieties covering configuration varieties. Certain one-dimensional slices of these coverings are particularly interesting Belyi maps. We present…

Number Theory · Mathematics 2016-08-31 David P. Roberts

We define a new Hurwitz problem which is essentially a small core of the simple Hurwitz problem. The corresponding Hurwitz numbers have simpler formulae, satisfy effective recursion relations and determine the simple Hurwitz numbers. We…

Geometric Topology · Mathematics 2013-12-31 Norman Do , Paul Norbury