English
Related papers

Related papers: Singular Hodge theory for combinatorial geometries

200 papers

The paper presents a proof of the Hodge Riemann relations for the combinatorial intersection cohomology of a polytope, as fist given by K.Karu, in terms of geometric operations on polytopes.

Algebraic Geometry · Mathematics 2007-05-23 G. Barthel , J. -P-Brasselet , K. -H. Fieseler , L. Kaup

We compute the Kazhdan-Lusztig polynomial of the uniform matroid of rank n-1 on n elements by proving that the i-th coefficient of is equal to the number of ways to choose i non-intersecting chords in an (n-i+1)-gon. We also show that the…

Combinatorics · Mathematics 2015-12-22 Nicholas Proudfoot , Max Wakefield , Benjamin Young

In this paper, we study the cohomology of semisimple local systems in the spirit of classical Hodge theory. On the one hand, we establish a generalization of Hodge-Riemann bilinear relations. For a semisimple local system on a smooth…

Algebraic Geometry · Mathematics 2024-12-13 Chuanhao Wei , Ruijie Yang

We give a concrete combinatorial interpretation of the coefficients of the Kazhdan-Lusztig polynomials of Dowling geometries, a family of matroids which generalizes braid matroids of types A and B. Furthermore, we interpret the coefficients…

Combinatorics · Mathematics 2026-05-06 Luis Ferroni , Matt Larson

Using Saito's theory of mixed Hodge modules, we study a generalization of Hellus-Schenzel's "cohomologically complete intersection" property. This property is equivalent to perversity of the shifted constant sheaf. We relate the generalized…

Algebraic Geometry · Mathematics 2025-11-06 Qianyu Chen , Bradley Dirks , Sebastian Olano

We prove the positivity of Kazhdan-Lusztig polynomials for sparse paving matroids, which are known to be logarithmically almost all matroids, but are conjectured to be almost all matroids. The positivity follows from a remarkably simple…

Combinatorics · Mathematics 2020-06-19 Kyungyong Lee , George D. Nasr , Jamie Radcliffe

We find a combinatorial formula which computes the first cotangent cohomology module of Stanley-Reisner rings associated to matroids. For arbitrary simplicial complexes we provide upper bounds for the dimensions of the multigraded…

Combinatorics · Mathematics 2023-03-06 William Bitsch , Alexandru Constantinescu

The Hard Lefschetz theorem is known to hold for the intersection cohomology of the toric variety associated to a rational convex polytope. One can construct the intersection cohomology combinatorially from the polytope, hence it is well…

Algebraic Geometry · Mathematics 2007-05-23 Kalle Karu

We give a $K$-theoretic and geometric interpretation for a generalized weighted Ehrhart theory of a full-dimensional lattice polytope $P$, depending on a given homogeneous polynomial function $\varphi$ on $P$, and with Laurent polynomial…

Algebraic Geometry · Mathematics 2025-12-30 Laurenţiu Maxim , Jörg Schürmann

We construct real polarizable Hodge structures on the reduced leafwise cohomology of K\"ahler-Riemann foliations by complex manifolds. As in the classical case one obtains a hard Lefschetz theorem for this cohomology. Serre's K\"ahlerian…

Differential Geometry · Mathematics 2007-05-23 Christopher Deninger , Wilhelm Singhof

We prove the structure theorem of the intersection complexes of toric varieties in the category of mixed Hodge modules. This theorem is due to Bernstein, Khovanskii and MacPherson for the underlying complexes with rational coefficients. As…

Algebraic Geometry · Mathematics 2020-06-24 Morihiko Saito

We develop a framework that systematically casts the solvability and uniqueness conditions of linearized geometric boundary-value problems into cohomological terms. The theory is designed to be applicable without assumptions on the…

Differential Geometry · Mathematics 2026-03-16 Roee Leder

This article constructs Von Neumann invariants for constructible complexes and coherent D-modules on compact complex manifolds, generalizing the work of the author on coherent L 2-cohomology. We formulate a conjectural generalization of…

Algebraic Geometry · Mathematics 2022-03-15 Philippe Eyssidieux

In two articles by Barthel, Brasselet, Fieseler and Kaup, and, Bressler and Lunts, a combinatorial theory of intersection cohomology and perverse sheaves has been developed on fans. In the first one, one tried to present everything on an…

Algebraic Geometry · Mathematics 2007-05-23 Karl-Heinz Fieseler

We give an explicit formula for the duality, previously conjectured by Horja and Borisov, of two systems of GKZ hypergeometric PDEs. We prove that in the appropriate limit this duality can be identified with the inverse of the Euler…

Algebraic Geometry · Mathematics 2024-03-13 Lev Borisov , Zengrui Han

If X is a complex projective variety with klt singularities, then the mixed Hodge structures on the first two singular cohomology groups are pure. We describe the pieces of the Hodge decomposition in terms of reflexive differential forms.…

Algebraic Geometry · Mathematics 2016-12-07 Martin Schwald

In its simplest form the Decomposition Theorem asserts that the rational intersection cohomology of a complex projective variety occurs as a summand of the cohomology of any resolution. This deep theorem has found important applications in…

Algebraic Geometry · Mathematics 2016-03-31 Geordie Williamson

We study the Hilbert series of four objects arising in the Chow-theoretic and Kazhdan-Lusztig framework of matroids. These are, respectively, the Hilbert series of the Chow ring, the augmented Chow ring, the intersection cohomology module,…

Combinatorics · Mathematics 2024-06-05 Luis Ferroni , Jacob P. Matherne , Matthew Stevens , Lorenzo Vecchi

We generalise the construction of Rouquier complexes to the setting of singular Soergel bimodules by taking minimal complexes of the restriction of Rouquier complexes. We show that they retain many of the properties of ordinary Rouquier…

Representation Theory · Mathematics 2020-02-06 Leonardo Patimo

We prove the decomposition theorem for Hodge modules with integral structure along proper K\"ahler morphisms, partially generalizing M. Saito's theorem for projective morphisms. Our proof relies on compactifications of period maps of…

Algebraic Geometry · Mathematics 2024-01-19 Mads Bach Villadsen