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Related papers: Murphy's Law for Algebraic Stacks

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This paper proves a result on the existence of finite flat scheme covers of Deligne-Mumford stacks. This result is used to prove that a large class of smooth Deligne-Mumford stacks with affine moduli space are quotient stacks, and in the…

Algebraic Geometry · Mathematics 2016-09-07 Andrew Kresch , Angelo Vistoli

We define two equivalent notions of twisted stable map from a curve to a Deligne-Mumford stack with projective moduli space, and we prove that twisted stable maps of fixed degree form a complete Deligne-Mumford stack with projective moduli…

Algebraic Geometry · Mathematics 2007-05-23 Dan Abramovich , Angelo Vistoli

The purpose of this note is to prove that there is an algebraic stack U parameterizing all curves. The curves that appear in the algebraic stack U are allowed to be arbitrarily singular, non-reduced, disconnected, and reducible. We also…

Algebraic Geometry · Mathematics 2010-11-30 Jack Hall

In view of applications to the construction of moduli spaces of objects in algebraic supergeometry, we start a systematic study of stacks in that context. After defining a superstack as a stack over the \'etale site of superschemes, we…

Algebraic Geometry · Mathematics 2025-05-30 Ugo Bruzzo , Daniel Hernández Ruipérez

We introduce a notion of Gieseker stability for coherent sheaves on tame Deligne-Mumford stacks with projective moduli scheme and some chosen generating sheaf on the stack in the sense of Olsson and Starr \cite{MR2007396}. We prove that…

Algebraic Geometry · Mathematics 2009-09-22 Fabio Nironi

We construct a proper moduli space which is a Deligne-Mumford stack parametrising quasimaps relative to a simple normal crossings divisor in any genus using logarithmic geometry. We show this moduli space admits a virtual fundamental class…

Algebraic Geometry · Mathematics 2024-01-15 Qaasim Shafi

We study the moduli of G-local systems on smooth but not necessarily proper complex algebraic varieties. We show that, when suitably considered as derived algebraic stacks, they carry natural Poisson structures, generalizing the well known…

Algebraic Geometry · Mathematics 2019-07-30 Tony Pantev , Bertrand Toen

We introduce semi-perfect obstruction theory of a Deligne-Mumford stack $X$ consisting of local perfect obstruction theories with weak comparisons on overlaps. We show that semi-perfect obstruction theory shares similar properties with…

Algebraic Geometry · Mathematics 2011-06-21 Huai-liang Chang , Jun Li

We consider the question of how geometric structures of a Deligne-Mumford stack affect its Gromov-Witten invariants. The two geometric structures studied here are {\em gerbes} and {\em root constructions}. In both cases, we explain…

Algebraic Geometry · Mathematics 2019-06-11 Hsian-Hua Tseng

If $X$ is a variety with an additional structure $\xi$, such as a marked point, a divisor, a polarization, a group structure and so forth, then it is possible to study whether the pair $(X,\xi)$ is defined over the field of moduli. There…

Algebraic Geometry · Mathematics 2023-11-29 Giulio Bresciani

We study closures of GL_2(R)-orbits on the total space of the Hodge bundle over the moduli space of curves under the assumption that they are algebraic manifolds. We show that, in the generic stratum, such manifolds are the whole stratum,…

Algebraic Geometry · Mathematics 2007-11-06 Martin Moeller

In this expository article we give a categorical definition of the integral cohomology ring of a stack. We show that for quotient stacks the categorical cohomology may be identified with equivariant cohomology. Via this identification we…

Algebraic Geometry · Mathematics 2011-08-08 Dan Edidin

In arXiv:2407.11958, a moduli stack parametrizing $I$--indexed diagrams of Higgs bundles over a base stack $X$ was constructed for any finite simplicial set $I$, inspiring speculations about extending the non-Abelian Hodge correspondence to…

Algebraic Geometry · Mathematics 2026-05-01 Mahmud Azam , Steven Rayan

There is a well-known stratification of the moduli space $M_g$ of Deligne-Mumford stable curves of genus $g$ by the loci of stable curves with a fixed number $i$ of nodes, where $i \le 3g-3$. The associated moduli stack ${\cal M}_g$ admits…

Algebraic Geometry · Mathematics 2007-05-23 Joerg Zintl

The real points of the Deligne-Knudsen-Mumford moduli space of marked points on the sphere has a natural tiling by associahedra. We extend this idea to create a moduli space tiled by cyclohedra. We explore the structure of this space,…

Quantum Algebra · Mathematics 2007-05-23 Satyan L. Devadoss

Moduli of vector bundles on stacky curves behave similarly to moduli of vector bundles on curves, except there are additional numerical invariants giving many different notions of stability. We apply the existence criterion for good moduli…

Algebraic Geometry · Mathematics 2024-07-08 Chiara Damiolini , Victoria Hoskins , Svetlana Makarova , Lisanne Taams

We show that the moduli space of rank three toric vector bundles on smooth projective toric varieties satisfies Murphy's law, that is, every singularity type of finite type arises somewhere on this space.

Algebraic Geometry · Mathematics 2020-02-04 Bernt Ivar Utstøl Nødland

We develop a theory of good moduli spaces for derived Artin stacks, which naturally generalizes the classical theory of good moduli spaces introduced by Alper. As such, many of the fundamental results and properties regarding good moduli…

Algebraic Geometry · Mathematics 2026-05-15 Eric Ahlqvist , Jeroen Hekking , Michele Pernice , Michail Savvas

After introducing some motivations for this survey, we describe a formalism to parametrize a wide class of algebraic structures occurring naturally in various problems of topology, geometry and mathematical physics. This allows us to define…

Algebraic Topology · Mathematics 2016-12-16 Sinan Yalin

We attempt to develop a general algebro-geometric study of the moduli stack of commutative, 1-parameter formal Lie groups. We emphasize the pro-algebraic structure of this stack: it is the inverse limit, over varying n, of moduli stacks of…

Algebraic Geometry · Mathematics 2007-09-28 Brian D. Smithling