English
Related papers

Related papers: Central extensions and Riemann-Roch theorem on alg…

200 papers

In this paper we study universal central extensions and non-abelian tensor product of hom-Lie-Rinehart algebras. We discuss about universal $\alpha$- central extensions, and, lifting of automorphisms and $\alpha$-derivations to central…

K-Theory and Homology · Mathematics 2018-03-13 Ashis Mandal , Satyendra Kumar Mishra

For certain tame abelian covers of arithmetic surfaces X/Y we obtain striking formulas, involving a quadratic form derived from intersection numbers, for the equivariant Euler characteristics of both the canonical sheaf !X/Y and also its…

Number Theory · Mathematics 2010-09-03 Ph. Cassou-Nogu`es , M. J. Taylor

The Riemann-Roch theorem is of utmost importance in the algebraic geometric theory of compact Riemann surfaces. It tells us how many linearly independent meromorphic functions there are having certain restrictions on their poles. The aim of…

Complex Variables · Mathematics 2007-06-20 A. Lesfari

Our aim in this paper is to provide a theory of discrete Riemann surfaces based on quadrilateral cellular decompositions of Riemann surfaces together with their complex structure encoded by complex weights. Previous work, in particular of…

Complex Variables · Mathematics 2017-04-11 Alexander I. Bobenko , Felix Günther

We construct the universal central extension of the Lie algebra of exact divergence-free vector fields, proving a conjecture by Claude Roger from 1995. The proof relies on the analysis of a Leibniz algebra that underlies these vector…

Differential Geometry · Mathematics 2025-07-24 Bas Janssens , Leonid Ryvkin , Cornelia Vizman

We consider a smooth groupoid of the form \Sigma\rtimes\Gamma where \Sigma is a Riemann surface and \Gamma a discrete pseudogroup acting on \Sigma by local conformal diffeomorphisms. After defining a K-cycle on the crossed product…

Mathematical Physics · Physics 2009-10-31 Denis Perrot

We study locally free sheaves of rank two on the projective line over the integers, especially indecomposable ones. Subsequently we apply various concepts of Arakelov geometry to these sheaves. We compute for example the arithmetic Chern…

Algebraic Geometry · Mathematics 2014-08-13 Fabian Reede

The goal of this paper is to prove a version of the non-abelian localization theorem for the rational equivariant K-theory of a smooth variety $X$ with the action of a linear algebraic group $G$. We then use this to prove a Riemann-Roch…

Algebraic Geometry · Mathematics 2009-06-16 Amalendu Krishna

Three types of reciprocity laws for arithmetic surfaces are established. For these around a point or along a vertical curve, we first construct $K_2$ type central extensions, then introduce reciprocity symbols, and finally prove the law as…

Algebraic Geometry · Mathematics 2016-03-09 Kotaro Sugahara , Lin Weng

In the present paper continuing our previous work we prove an extension theorem for matrices with entries in the algebra of bounded holomorphic functions defined on an unbranched covering of a Caratheodory hyperbolic Riemann surface of…

Complex Variables · Mathematics 2008-01-14 Alexander Brudnyi

We review and analyse techniques from the literature for extending a normed algebra, A to a normed algebra, B, so that B has interesting or desirable properties which A may lack. For example, B might include roots of monic polynomials over…

Functional Analysis · Mathematics 2007-05-23 Thomas William Dawson

We prove a Riemann-Roch theorem of an entirely novel nature for divisors on the Arakelov compactification of the algebraic spectrum of the integers. This result relies on the introduction of three key concepts: the cohomologies (attached to…

Algebraic Geometry · Mathematics 2023-03-10 Alain Connes , Caterina Consani

We consider a central extension of the sheaf of Lie algebras of maps from a manifold into a finite-dimensional simple Lie algebra, together with the sheaf of vector fields. Using vertex algebra methods we construct sheaves of modules for…

Representation Theory · Mathematics 2011-09-13 Yuly Billig

We consider the local analytic behavior for a family of holomorphic differentials on a family of degenerating annuli. Three results and discussion are presented. The first is the normal families Lemma 1. The second is an isomorphism of…

Geometric Topology · Mathematics 2011-11-24 Scott A. Wolpert

Let X_0 be a compact connected Riemann surface of genus g with D_0\subset X_0 an ordered subset of cardinality n, and let E_G be a holomorphic principal G-bundle on X_0, where G is a complex reductive affine algebraic group, that admits a…

Algebraic Geometry · Mathematics 2015-10-20 Indranil Biswas , Viktoria Heu , Jacques Hurtubise

We prove an equivariant Riemann-Roch formula for divisors on algebraic curves over perfect fields. By reduction to the known case of curves over algebraically closed fields, we first show a preliminary formula with coefficients in Q. We…

Algebraic Geometry · Mathematics 2008-04-11 Helena B. Fischbacher-Weitz , Bernhard Köck

We prove a generalisation of the Grothendieck-Riemann-Roch theorem, which is valid for any proper and flat morphism between noetherian and separated schemes of odd characteristic.

Algebraic Geometry · Mathematics 2023-06-06 Damian Rössler

We develop linear discretization of complex analysis, originally introduced by R. Isaacs, J. Ferrand, R. Duffin, and C. Mercat. We prove convergence of discrete period matrices and discrete Abelian integrals to their continuous…

Complex Variables · Mathematics 2017-08-25 Alexander Bobenko , Mikhail Skopenkov

By Torelli topology the author understands aspects of the topology of surfaces (potentially) relevant to the study of Torelli groups. The extension problem in Torelli topology is the problem of determining when a diffeomorphism of compact…

Geometric Topology · Mathematics 2017-04-25 Nikolai V. Ivanov

We propose an algebraic method for the classification of branched Galois covers of a curve $X$ focused on studying Galois ring extensions of its geometric adele ring $\A_{X}$. As an application, we deal with cyclic covers; namely, we…

Algebraic Geometry · Mathematics 2026-03-16 Luis Manuel Navas Vicente , Francisco J. Plaza Martin