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We develop a generalization to non-Witt spaces of the intersection homology theory of Goresky-MacPherson. The second author has described the self-dual sheaves compatible with intersection homology, and the other authors have described a…

Geometric Topology · Mathematics 2013-08-20 Pierre Albin , Markus Banagl , Eric Leichtnam , Rafe Mazzeo , Paolo Piazza

In this paper, we prove a decomposition result for the Chow groups of projectivizations of coherent sheaves of homological dimension $\le 1$. In this process, we establish the decomposition of Chow groups for the cases of Cayley's trick and…

Algebraic Geometry · Mathematics 2021-07-21 Qingyuan Jiang

A reduced divisor on a nonsingular variety defines the sheaf of logarithmic 1-forms. We introduce a certain coherent sheaf whose double dual coincides with this sheaf. It has some nice properties, for example, the residue exact sequence…

Algebraic Geometry · Mathematics 2007-05-23 Igor V. Dolgachev

We study virtual invariants of Quot schemes parametrizing quotients of dimension at most 1 of the trivial sheaf of rank N on nonsingular projective surfaces. We conjecture that the generating series of virtual K-theoretic invariants are…

Algebraic Geometry · Mathematics 2021-02-23 Noah Arbesfeld , Drew Johnson , Woonam Lim , Dragos Oprea , Rahul Pandharipande

The $X$-rank of a point $p$ in projective space is the minimal number of points of an algebraic variety $X$ whose linear span contains $p$. This notion is naturally submultiplicative under tensor product. We study geometric conditions that…

Algebraic Geometry · Mathematics 2020-05-29 Edoardo Ballico , Alessandra Bernardi , Fulvio Gesmundo , Alessandro Oneto , Emanuele Ventura

In this paper, we present necessary and sufficient combinatorial conditions for a link to be projective, that is, a link in $RP^3$. This characterization is closely related to the notions of antipodally self-dual and antipodally symmetric…

Geometric Topology · Mathematics 2024-01-01 L. Montejano , J. Ramirez Alfonsin , I. Rasskin

To construct a Paley graph, we fix a finite field and consider its elements as vertices of the Paley graph. Two vertices are connected by an edge if their difference is a square in the field. We will study some important properties of the…

Combinatorics · Mathematics 2012-03-09 Ahmed Noubi Elsawy

We investigate restricted Lie algebras arising as analogues of (twisted) right-angled Artin groups and right-angled Coxeter groups over fields of characteristic two. These algebras are defined via quadratic relations determined by decorated…

Rings and Algebras · Mathematics 2026-04-22 Simone Blumer

A Pfaff field on a projective space is a map from the sheaf of differential s-forms, for a certain s, to an invertible sheaf. The interesting ones are those arising from a Pfaff system, as they give rise to a distribution away from their…

Algebraic Geometry · Mathematics 2009-02-16 Joana D. A. S. Cruz , Eduardo Esteves

Given any unoriented link diagram, a group of new knot invariants are constructed. Each of them satisfies a generalized 4 term skein relation. The coefficients of each invariant is from a commutative ring. Homomorphisms and representations…

Geometric Topology · Mathematics 2010-04-14 Zhiqing Yang , Jifu Xiao

The purpose of this paper is to present a mathematical theory of the half-twisted $(0,2)$ gauged linear sigma model and its correlation functions that agrees with and extends results from physics. The theory is associated to a smooth…

Algebraic Geometry · Mathematics 2016-10-04 Ron Donagi , Josh Guffin , Sheldon Katz , Eric Sharpe

In this paper we give a complete classification of cyclically graded semisimple Lie algebras that afford cuspidal character sheaves and determine the support of the cuspidal character sheaves. This constitutes a major step towards the…

Representation Theory · Mathematics 2025-12-24 Wille Liu , Kari Vilonen , Ting Xue

In this paper, we introduce multiple skew-orthogonal polynomials and investigate their connections with classical integrable systems. By using Pfaffian techniques, we show that multiple skew-orthogonal polynomials can be expressed by…

Mathematical Physics · Physics 2023-02-07 Shi-Hao Li , Bo-Jian Shen , Jie Xiang , Guo-Fu Yu

We develop a theory of primitive pairs for $\mathbb{Z}$-graded Lie algebras when the sheaves have coefficients in a field $\Bbbk$ of positive characteristic, providing a graded analogue of the role played by cuspidal pairs in the…

Representation Theory · Mathematics 2025-10-29 Tamanna Chatterjee

We give classifications of linear orbits of pairs of square matrices with non-vanishing discriminant polynomials over a field in terms of certain coherent sheaves with additional data on closed subschemes of the projective line. Our results…

Algebraic Geometry · Mathematics 2015-03-27 Yasuhiro Ishitsuka , Tetsushi Ito

We prove invariance results for the cohomology groups of ideal sheaves of simple normal crossing divisors under (a restricted class of) birational morphisms of pairs in arbitrary characteristic, assuming a conjecture regarding the existence…

Algebraic Geometry · Mathematics 2023-10-17 Charles Godfrey

A tuple (s1,t1,s2,t2) of vertices in a simple undirected graph is 2-linked when there are two vertex-disjoint paths respectively from s1 to t1 and s2 to t2. A graph is 2-linked when all such tuples are 2-linked. We give a new and simple…

Data Structures and Algorithms · Computer Science 2025-08-15 Samuel Humeau , Damien Pous

The Pareto sum of two-dimensional point sets $P$ and $Q$ in $\mathbb{R}^2$ is defined as the skyline of the points in their Minkowski sum. The problem of efficiently computing the Pareto sum arises frequently in bi-criteria optimization…

Computational Geometry · Computer Science 2026-03-27 Geri Gokaj , Marvin Künnemann , Sabine Storandt , Carina Truschel

We extend path analysis by showing that, for a singly-connected path diagram, the partial covariance of two random variables factorizes over the nodes and edges in the path between the variables. This result allows us to determine the…

Methodology · Statistics 2022-06-24 Jose M. Peña

We prove the Mirkovi\'c-Vilonen conjecture: the integral local intersection cohomology groups of spherical Schubert varieties on the affine Grassmannian have no p-torsion, as long as p is outside a certain small and explicitly given set of…

Representation Theory · Mathematics 2015-09-21 Pramod N. Achar , Laura Rider