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Related papers: Virtual classes of Artin stacks

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We construct a new compactification of the moduli space of maps from pointed nonsingular projective stable curves to a nonsingular projective variety with prescribed ramification indices at the points. It is shown to be a proper…

Algebraic Geometry · Mathematics 2011-06-01 Bumsig Kim , Andrew Kresch , Yong-Geun Oh

In the category of finitely generated modules over an artinian ring, we classify all the abelian exact subcategories closed under predecessors or, equivalently, all the split torsion pairs with torsion-free class closed under quotients.

Rings and Algebras · Mathematics 2007-05-23 Ibrahim Assem , Manuel Saorin

We consider hereditary Artin algebras over arbitrary fields and prove that there is a natural bijection between the Weyl groups and the sets of full additive cofinite submodule closed subcategories of the module categories. While Oppermann,…

Representation Theory · Mathematics 2017-10-17 Apolonia Gottwald

We introduce and study a natural class of fields in which certain first-order definable sets are existentially definable, and characterise this class by a number of equivalent conditions. We show that global fields belong to this class, and…

Logic · Mathematics 2023-06-22 Philip Dittmann , Dion Leijnse

We study the algebraic structure of the automorphism group of a general right-angled Artin group. We show that this group is virtually torsion-free and has finite virtual cohomological dimension. This generalizes results proved by the…

Group Theory · Mathematics 2008-07-03 Ruth Charney , Karen Vogtmann

Following the philosophy of arithmetic topology, we describe a point of view which helps look at surfaces and $p$-adic fields in a "uniform way", and show that results on mapping class groups can be extended to this point of view, and thus…

Number Theory · Mathematics 2023-03-09 Nadav Gropper

We prove a new structural result for the spherical Tits building attached to SL_n(K) for many number fields K, and more generally for the fraction fields of many Dedekind domains O: the Steinberg module St_n(K) is generated by integral…

Number Theory · Mathematics 2020-06-09 Thomas Church , Benson Farb , Andrew Putman

We prove that all pure submodules of a finite rank torsion-free module $A$ over a Dedekind domain are $A$-generated if and only if $A$ has a rank $1$ direct summand $B$ such that $\mathbf{type}(B)$ is the inner type of $A$.

Commutative Algebra · Mathematics 2018-08-07 Simion Breaz

We compute the quantum Euler class of Fano complete intersections X in a projective space. In particular, we prove a recent conjecture of A. Buch and R. Pandharipande. Finally we apply our result to obtain formulas for the virtual Tevelev…

Algebraic Geometry · Mathematics 2022-04-05 Alessio Cela

There is a well developed intersection theory on smooth Artin stacks with quasi-affine diagonal. However, for Artin stacks whose diagonal is not quasi-finite the notion of the degree of a Chow cycle is not defined. In this paper we propose…

Algebraic Geometry · Mathematics 2012-01-11 Dan Edidin , Yogesh More

We prove that the dg category of perfect complexes on a smooth, proper Deligne-Mumford stack over a field of characteristic zero is geometric in the sense of Orlov, and in particular smooth and proper. On the level of triangulated…

Algebraic Geometry · Mathematics 2018-08-14 Daniel Bergh , Valery A. Lunts , Olaf M. Schnürer

We introduce the universal virtual braid group $UV_n(c)$, which provides a unified algebraic framework for virtual braid--type structures with $c$ types of crossings and admits natural quotient maps onto the standard families in the…

Group Theory · Mathematics 2026-04-10 Oscar Ocampo

This paper is the sequel to [PTVV] (IHES Vol. 117, 2013). We develop a general and flexible context for differential calculus in derived geometry, including the de Rham algebra and polyvector fields. We then introduce the formalism of…

Algebraic Geometry · Mathematics 2018-05-10 D. Calaque , T. Pantev , B. Toen , M. Vaquie , G. Vezzosi

A complete description of the deformation classes of real ruled manifolds is given. In particular, we prove that once the complex deformation class is fixed, the real deformation class is prescribed by the topology of the real structure.

Algebraic Geometry · Mathematics 2007-05-23 Jean-Yves Welschinger

Artin's conjecture is established for all forms that can be realised as a diagonal form on an hyperplane.

Number Theory · Mathematics 2018-06-14 Jörg Brüdern , Olivier Robert

Crystalline graded rings are generalizations of certain classes of rings like generalized twisted group rings, generalized Weyl algebras, and generalized skew crossed products. When the base ring is a commutative Dedekind domain, two…

Rings and Algebras · Mathematics 2009-03-27 Tim Neijens , Fred Van Oystaeyen

Using the Morita-type embedding, we show that any exact category with enough projectives has a realization as a (pre)resolving subcategory of a module category. When the exact category has enough injectives, the image of the embedding can…

Representation Theory · Mathematics 2019-07-30 Haruhisa Enomoto

We construct an almost perfect obstruction theory of virtual dimension zero on the Quot scheme parametrizing zero-dimensional quotients of a locally free sheaf on a smooth projective $3$-fold. This gives a virtual class in degree zero and…

Algebraic Geometry · Mathematics 2025-06-18 Solomiya Mizyuk

Let $\Delta$ be the Artin complex of the Artin group of type $D_n$. This complex is also called the spherical Deligne complex of type $D_n$. We show certain types of 6-cycles in the 1-skeleton of $\Delta$ either have a center, which is a…

Group Theory · Mathematics 2024-06-13 Jingyin Huang

We prove several results on the model theory of Artin groups, focusing on Artin groups which are ``far from right-angled Artin groups''. The first result is that if $\mathcal{C}$ is a class of Artin groups whose irreducible components are…

Logic · Mathematics 2025-07-30 Alberto Cassella , Gianluca Paolini , Giovanni Paolini