English
Related papers

Related papers: Intersection complexes of toric varieties and mixe…

200 papers

Given a smooth compact complex surface together with a holomorphic line bundle on it, using the theory of Hodge modules, we compute the twisted Hodge groups/numbers of Hilbert schemes (or Douady spaces) of points on the surface with values…

Algebraic Geometry · Mathematics 2024-12-16 Lie Fu

This note proves combinatorially that the intersection pairing on the middle dimensional compactly supported cohomology of a smooth toric hyperkaehler variety is always definite, providing a large number of non-trivial L^2 harmonic forms…

Algebraic Geometry · Mathematics 2007-05-23 Tamas Hausel , Edward Swartz

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

We give a geometric proof of the Decomposition Theorem of Beilinson, Bernstein, Deligne and Gabber for the direct image of the intersection cohomology complex under a proper map of complex algebraic varieties. The method rests on new…

Algebraic Geometry · Mathematics 2007-05-23 Mark Andrea A. de Cataldo , Luca Migliorini

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

Let $U$ be a smooth connected complex algebraic variety, and let $f\colon U\to \mathbb C^*$ be an algebraic map. To the pair $(U,f)$ one can associate an infinite cyclic cover $U^f$, and (homology) Alexander modules are defined as the…

Algebraic Geometry · Mathematics 2024-01-03 Eva Elduque , Moisés Herradón Cueto

We compute the intersection cohomology of the moduli spaces $M_{r,d}$ of semistable vector bundles having rank $r$ and degree $d$ over a curve. We do this by relating the Hodge-Deligne polynomial of the intersection cohomology of $M_{r,d}$…

Algebraic Geometry · Mathematics 2025-04-03 Sergey Mozgovoy , Markus Reineke

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 construct motivic invariants of a subvariety of an algebraic torus from its tropicalization and initial degenerations. More specifically, we introduce an invariant of a compactification of such a variety called the "tropical motivic…

Algebraic Geometry · Mathematics 2019-02-20 Eric Katz , Alan Stapledon

We show that very general hypersurfaces in odd-dimensional simplicial projective toric varieties verifying a certain combinatorial property satisfy the Hodge conjecture (these include projective spaces). This gives a connection between the…

Algebraic Geometry · Mathematics 2021-10-12 Ugo Bruzzo , Antonella Grassi

In a previous article, we proved tight lower bounds for the coefficients of the generalized $h$-vector of a centrally symmetric rational polytope using intersection cohomology of the associated projective toric variety. Here we present a…

Algebraic Geometry · Mathematics 2007-05-23 Annette A'Campo-Neuen

This note studies the behavior of Euler characteristics and of intersection homology Euler characterstics under proper morphisms of algebraic (or analytic) varieties. The methods also yield, for algebraic (or analytic) varieties, formulae…

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

In [5] I.P. Goulden, D.M. Jackson, and R. Vakil formulated a conjecture relating certain Hurwitz numbers (enumerating ramified coverings of the sphere) to the intersection theory on a conjectural Picard variety. We are going to use their…

Algebraic Geometry · Mathematics 2018-07-18 Sergey Shadrin , Dimitri Zvonkine

We show how to equip the cone complexes of toroidal embeddings with additional structure that allows to define a balancing condition for weighted subcomplexes. We then proceed to develop the foundations of an intersection theory on cone…

Algebraic Geometry · Mathematics 2018-02-07 Andreas Gross

Let $f:\CN \rightarrow \C $ be a polynomial, which is transversal (or regular) at infinity. Let $\U=\CN\setminus f^{-1}(0)$ be the corresponding affine hypersurface complement. By using the peripheral complex associated to $f$, we give…

Algebraic Topology · Mathematics 2016-01-20 Yongqiang Liu , Laurentiu Maxim

In this paper, we prove the Shafarevich conjecture for certain complete intersections of hypersurfaces in abelian varieties defined over a number field $K$ using the Lawrence-Venkatesh method. The main new inputs we need are computation of…

Number Theory · Mathematics 2025-06-19 Frank Lu

We give an elementary proof of the fact that a pure-dimensional closed subvariety of a complex abelian variety has a signed intersection homology Euler characteristic. We also show that such subvarieties which, moreover, are local complete…

Algebraic Topology · Mathematics 2018-04-24 Eva Elduque , Christian Geske , Laurentiu Maxim

We discover that tautological intersection numbers on $\bar{\mathcal{M}}_{g, n}$, the moduli space of stable genus $g$ curves with $n$ marked points, are evaluations of Ehrhart polynomials of partial polytopal complexes. In order to prove…

Algebraic Geometry · Mathematics 2022-09-29 Adam Afandi

We prove a bound conjectured by Itenberg on the Betti numbers of real algebraic hypersurfaces near non-singular tropical limits. These bounds are given in terms of the Hodge numbers of the complexification. To prove the conjecture we…

Algebraic Geometry · Mathematics 2019-11-14 Arthur Renaudineau , Kristin Shaw

Using a refinement of the differential method introduced by Oguiso and Yu, we provide effective conditions under which the automorphisms of a smooth degree $d$ hypersurface of $\mathbf{P}^{n+1}$ are given by generalized triangular matrices.…

Algebraic Geometry · Mathematics 2024-04-19 Víctor González-Aguilera , Alvaro Liendo , Pedro Montero , Roberto Villaflor Loyola