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Related papers: Intersection Cohomology of reductive varieties

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This paper explicitly describes Hodge structures of complete intersections of ample hypersurfaces in compact simplicial toric varieties.

alg-geom · Mathematics 2007-05-23 Anvar R. Mavlyutov

We investigate decompositions of Betti diagrams over a polynomial ring within the framework of Boij--Soederberg theory. That is, given a Betti diagram, we decompose it into pure diagrams. Relaxing the requirement that the degree sequences…

Commutative Algebra · Mathematics 2017-04-25 Courtney Gibbons , Jack Jeffries , Sarah Mayes , Claudiu Raicu , Branden Stone , Bryan White

We introduce several new quantum algorithms for estimating homological invariants, specifically Betti numbers and persistent Betti numbers, of a simplicial complex given via a structured classical input. At the core of our algorithm lies…

Quantum Physics · Physics 2026-04-28 Nhat A. Nghiem

We outline a strategy for computing intersection numbers on smooth varieties with torus actions using a residue formula of Bott. As an example, Gromov-Witten numbers of twisted cubic and elliptic quartic curves on some general complete…

alg-geom · Mathematics 2008-02-03 G. Ellingsrud , S. A. Strømme

In this paper we study the \'etale cohomology groups associated to abelian varieties. We obtain necessary and sufficient conditions for an abelian variety to have semistable reduction (or purely additive reduction which becomes semistable…

Algebraic Geometry · Mathematics 2007-05-23 A. Silverberg , Yu. G. Zarhin

In this paper we introduce the concept of characteristic number that are proven to be useful in the study of the combinatorics of graph cohomology. We claim that it is a good combinatorial counterpart for geometric Betti numbers. We then…

Symplectic Geometry · Mathematics 2012-06-28 Shisen Luo

The aim of this paper is to study the behavior of Hodge-theoretic (intersection homology) genera and their associated characteristic classes under proper morphisms of complex algebraic varieties. We obtain formulae that relate (parametrized…

Algebraic Geometry · Mathematics 2012-04-03 Sylvain E. Cappell , Laurentiu G. Maxim , Julius L. Shaneson

In this article we study the equivariant elliptic cohomology of complex toric varieties. We prove a partial reconstruction theorem showing that equivariant elliptic cohomology encodes considerable non-trivial information on the equivariant…

Algebraic Geometry · Mathematics 2022-10-21 Sarah Scherotzke , Nicolo Sibilla

We prove that the intersection cohomology of the Baily-Borel compactification of a complex Shimura variety is identified with the top weight quotient of the mixed Hodge structure on the reductive Borel-Serre compactification. This yields…

Algebraic Geometry · Mathematics 2026-03-26 Mingyu Ni

In this paper, we introduce new combinatorial invariants of any finite simple graph, which arise in toric topology. We compute the $i$-th (rational) Betti number and Euler characteristic of the real toric variety associated to a graph…

Algebraic Topology · Mathematics 2015-07-31 Suyoung Choi , Hanchul Park

We established the associativity of the quantum cohomologies of homogeneous varieties by using degeneration method in algebraic geometry.

alg-geom · Mathematics 2008-02-03 Jun Li , Gang Tian

Different techniques from machine learning are applied to the problem of computing line bundle cohomologies of (hypersurfaces in) toric varieties. While a naive approach of training a neural network to reproduce the cohomologies fails in…

High Energy Physics - Theory · Physics 2019-01-09 Daniel Klaewer , Lorenz Schlechter

We give algorithms for the computation of the algebraic de Rham cohomology of open and closed algebraic sets inside projective space or other smooth complex toric varieties. The methods, which are based on Gr\"obner basis computations in…

Algebraic Geometry · Mathematics 2009-09-25 Uli Walther

There exist several homology theories for singular spaces that satisfy generalized Poincar\'e duality, including Goresky-MacPherson's intersection homology, Cheeger's $L^2$ cohomology and the homology of intersection spaces. The…

Algebraic Topology · Mathematics 2024-06-04 Markus Banagl , Shahryar Ghaed Sharaf

The purpose of this paper is to provide a way to compute the intersection cohomology of the GIT quotient of a nonsingular projective variety. We show that the middle perversity intersection cohomology of the GIT quotient $M//G$ is naturally…

Algebraic Geometry · Mathematics 2007-05-23 Young-Hoon Kiem

Topological data analysis has emerged as a powerful tool for analyzing large-scale data. An abstract simplicial complex, in principle, can be built from data points, and by using tools from homology, topological features could be…

Quantum Physics · Physics 2025-12-24 Nhat A. Nghiem , Xianfeng David Gu , Tzu-Chieh Wei

A permutohedral variety is a remarkable object in various areas of mathematics, and its topological invariants are widely recognized. However, only little is known about a real permutohedral variety, that is, the real locus of a…

Algebraic Topology · Mathematics 2024-10-01 Suyoung Choi , Younghan Yoon

In this note, (rational) Betti numbers of homotopy colimits for toric diagrams and their classifying spaces are described in terms of sheaf cohomology over CW posets. We prove for any $T$-diagram $D$ over any CW poset that…

Algebraic Topology · Mathematics 2026-04-30 Grigory Solomadin

Wonderful compactifications of adjoint reductive groups over an algebraically closed field play an important role in algebraic geometry and representation theory. In this paper, we construct an equivariant compactification for adjoint…

Algebraic Geometry · Mathematics 2025-06-04 Shang Li

We study the cohomology of broken toric varieties via the derived push-forward of the constant sheaf to a complex of polytopes, proving a Deligne-type decomposition theorem, degeneration of the associated Leray-Serre spectral sequence, and…

Algebraic Geometry · Mathematics 2024-06-12 Evan Sundbo