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Related papers: Constructible sheaves on toric varieties

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We characterise and investigate co-Higgs sheaves and associated algebraic and combinatorial invariants on toric varieties. In particular, we compute explicit examples.

Algebraic Geometry · Mathematics 2020-10-20 Klaus Altmann , Frederik Witt

In this paper, we prove that a smooth projective globally $F$-split variety with numerically flat tangent bundle is an \'etale quotient of an ordinary abelian variety. We also show its logarithmic analog, which contains a characterization…

Algebraic Geometry · Mathematics 2023-03-20 Sho Ejiri , Shou Yoshikawa

In the context of uniformisation problems, we study projective varieties with klt singularities whose cotangent sheaf admits a projectively flat structure over the smooth locus. Generalising work of Jahnke-Radloff, we show that torus…

Algebraic Geometry · Mathematics 2022-01-10 Daniel Greb , Stefan Kebekus , Thomas Peternell

Toric subvarieties of projective space are classified up to projective automorphisms.

Representation Theory · Mathematics 2019-09-11 Friedrich Knop , Rainer Sinn

We describe categories of equivariant vector bundles on certain toroidal spherical varieties in linear algebra terms: vector spaces equipped with filtrations, group and Lie algebra actions, and linear maps preserving these structures.

Algebraic Geometry · Mathematics 2009-08-28 Aravind Asok , James Parson

Let $X$ be any rational surface. We construct a tilting bundle $T$ on $X$. Moreover, we can choose $T$ in such way that its endomorphism algebra is quasi-hereditary. In particular, the bounded derived category of coherent sheaves on $X$ is…

Algebraic Geometry · Mathematics 2017-06-27 Lutz Hille , Markus Perling

We show that bounded type implies finite type for a constructible subcategory of the module category of a finitely generated algebra over a field, which is a variant of the first Brauer-Thrall conjecture. A full subcategory is constructible…

Representation Theory · Mathematics 2025-07-31 Kevin Schlegel , Andres Fernandez Herrero

We classify (semi)stable sheaves on a rational curve with one node. The results are based on the classification of indecomposable torsion-free sheaves due to Drozd and Greuel "Tame and wild projective curves and classification of vector…

Algebraic Geometry · Mathematics 2007-05-23 Sergey Mozgovoy

Suppose $C$ is a smooth projective curve of genus 1 over a perfect field $F$, and $E$ is its Jacobian. In the case that $C$ has no $F$-rational points, so that $C$ and $E$ are not isomorphic, $C$ is an $E$-torsor with a class $\delta(C)\in…

Algebraic Geometry · Mathematics 2025-07-10 Niranjan Ramachandran , Jonathan Rosenberg

We show how to use information about the equations defining secant varieties to smooth projective varieties in order to construct a natural collection of birational transformations. These were first constructed as flips in the case of…

Algebraic Geometry · Mathematics 2007-05-23 Peter Vermeire

It has long been known that to a complex cubic surface or threefold one can canonically associate a principally polarized abelian variety. We give a construction which works for cubics over an arithmetic base. This answers, away from the…

Algebraic Geometry · Mathematics 2020-02-27 Jeff Achter

A general problem in complex cobordism theory is to find useful representatives for cobordism classes. One particularly convenient class of complex manifolds consists of smooth projective toric varieties. The bijective correspondence…

Algebraic Topology · Mathematics 2013-12-17 Andrew Wilfong

The purpose of this paper is to explain why the functor that sends a stratified topological space $S$ to the $\infty$-category of constructible (hyper)sheaves on $S$ with coefficients in a large class of presentable $\infty$categories is…

Algebraic Topology · Mathematics 2022-09-09 Peter J. Haine , Mauro Porta , Jean-Baptiste Teyssier

We construct an abelian category A(G) of sheaves over a category of closed subgroups of the r-torus G and show it is of finite injective dimension. It can be used as a model for rational $G$-spectra in the sense that there is a homology…

Algebraic Topology · Mathematics 2007-05-23 J. P. C. Greenlees

Graded Hecke algebras can be constructed in terms of equivariant cohomology and constructible sheaves on nilpotent cones. In earlier work, their standard modules and their irreducible modules where realized with such geometric methods. We…

Representation Theory · Mathematics 2025-01-20 Maarten Solleveld

We define the notion of a sheaf over a complex of groups. As an application, we give a criterion for the developability of a complex of groups. When the developability is witnessed by a morphism to $\mathrm{GL}(V)$ for some $V$, our…

Group Theory · Mathematics 2022-02-15 Joshua L. Faber

Topologically, compact toric varieties can be constructed as identification spaces: they are quotients of the product of a compact torus and the order complex of the fan. We give a detailed proof of this fact, extend it to the non-compact…

Algebraic Topology · Mathematics 2010-10-25 Matthias Franz

We study the equivariant real structures on complex horospherical varieties, generalizing classical results known for toric varieties and flag varieties. In particular, we obtain a necessary and sufficient condition for the existence of…

Algebraic Geometry · Mathematics 2021-03-22 Lucy Moser-Jauslin , Ronan Terpereau , Mikhail Borovoi

We present various facts on the graded Betti table of a projectively embedded toric surface, expressed in terms of the combinatorics of its defining lattice polygon. These facts include explicit formulas for a number of entries, as well as…

Algebraic Geometry · Mathematics 2016-12-05 Wouter Castryck , Filip Cools , Jeroen Demeyer , Alexander Lemmens

We firstly introduce some key concepts in category theory, such as quotient category, completion of limits, $\mathrm{Mor}$ category, and so on; then give the concept of topology algebras and sheaves, and discuss how to restore the structue…

Category Theory · Mathematics 2019-06-11 Dezhao Zhang