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Related papers: Equivariant intersection theory

200 papers

We prove several completion theorems for equivariant K-theory and cyclic homology of schemes with group action over a field. One of these shows that for an algebraic space over a field acted upon by a linear algebraic group, the derived…

Algebraic Geometry · Mathematics 2025-02-14 Amalendu Krishna , Ritankar Nath

The Hirzebruch $td_y(X)$ class of a complex manifold X is a formal combination of Chern characters of the sheaves of differential forms multiplied by the Todd class. The related $\chi_y$-genus admits a generalization for singular complex…

Algebraic Geometry · Mathematics 2015-08-11 Andrzej Weber

We prove a decomposition theorem for the equivariant K-theory of actions of affine group schemes G of finite type over a field on regular separated noetherian algebraic spaces, under the hypothesis that the actions have finite geometric…

Algebraic Geometry · Mathematics 2007-05-23 Gabriele Vezzosi , Angelo Vistoli

In this paper we use formal group rings to construct an algebraic model of the $T$-equivariant oriented cohomology of smooth toric varieties. Then we compare our model with known results of equivariant cohomology of toric varieties to…

Algebraic Geometry · Mathematics 2015-03-27 Wanshun Wong

We give an example of an algebraic torus $T$ such that the group $\operatorname{CH}^2(BT)_{\operatorname{tors}}$ is non-trivial. This answers a question of Blinstein and Merkurjev.

Algebraic Geometry · Mathematics 2021-05-19 Federico Scavia

In this paper, we define an action of the group of equivariant Cartier divisors on a toric variety X on the equivariant cycle groups of X, arising naturally from a choice of complement map on the underlying lattice. If X is nonsingular,…

Algebraic Geometry · Mathematics 2014-07-29 Benjamin P. Fischer , James E. Pommersheim

We introduce and study the continuous Rokhlin property for actions of compact groups on C*-algebras. An important technical result is a characterization of the continuous Rokhlin property in terms of asymptotic retracts. As a consequence,…

Operator Algebras · Mathematics 2021-10-14 Eusebio Gardella

This is the second in a series of papers. Here we develop here an intersection theory for manifolds equipped with an action of a finite group. As in our previous paper, our approach will be homotopy theoretic, enabling us to circumvent the…

Algebraic Topology · Mathematics 2009-01-23 John R. Klein , Bruce Williams

We introduce a torsor-theoretic obstruction to equivariant unirationality and show that it is also sufficient for actions of finite groups on toric varieties arising from automorphisms of the torus.

Algebraic Geometry · Mathematics 2025-06-10 Andrew Kresch , Yuri Tschinkel

The paper is based on a talk. Complete exposition is given in "Equivariant Hirzebruch class for singular varieties". Starting from the classical theory we describe Hirzebruch class and the related Todd genus of a complex singular algebraic…

Algebraic Geometry · Mathematics 2013-08-06 Andrzej Weber

We study the K-theory of actions of diagonalizable group schemes on noetherian regular separated algebraic spaces: our main result shows how to reconstruct the K-theory ring of such an action from the K-theory rings of the loci where the…

Algebraic Geometry · Mathematics 2007-05-23 Gabriele Vezzosi , Angelo Vistoli

This is a revised and shortened version of our paper "Equivariant intersection theory" (alg-geom/9603008). In particular, the sections on Riemann-Roch and localization are omitted. They will appear in separate papers, at which time…

alg-geom · Mathematics 2008-02-03 Dan Edidin , William Graham

This survey paper describes two geometric representations of the permutation group using the tools of toric topology. These actions are extremely useful for computational problems in Schubert calculus. The (torus) equivariant cohomology of…

Algebraic Topology · Mathematics 2007-06-05 Julianna S. Tymoczko

The fixed points of a natural torus action on the Hilbert schemes of points in C^2 are quiver varieties of infinite type A. The equivariant cohomology of the Hilbert schemes and quiver varieties can be given the structure of bosonic and…

Representation Theory · Mathematics 2011-07-13 Alistair Savage

We study intersection theoretic problems in the setting of Chow-Witt groups with coefficients in a fixed Milnor-Witt cycle algebra over a perfect field. We prove that the product maps on such groups satisfy the following property: given two…

Algebraic Geometry · Mathematics 2021-12-13 Niels Feld

The rational Borel equivariant cohomology for actions of a compact connected Lie group is determined by restriction of the action to a maximal torus. We show that a similar reduction holds for any compact Lie group $G$ when there is a…

Algebraic Topology · Mathematics 2024-02-14 Sergio Chaves

This paper shows that the integral equivariant cohomology Chern numbers completely determine the equivariant geometric unitary bordism classes of closed unitary $G$-manifolds, which gives an affirmative answer to the conjecture posed by…

Algebraic Topology · Mathematics 2019-03-19 Zhi Lü , Wei Wang

Let M be a manifold carrying the action of a Lie group G, and A a Lie algebroid on M equipped with a compatible infinitesimal G-action. Out of these data we construct an equivariant Lie algebroid cohomology and prove for compact G a related…

Differential Geometry · Mathematics 2009-11-02 U. Bruzzo , L. Cirio , P. Rossi , V. Rubtsov

We describe the Chow homology and cohomology of toric variety bundles, with no restrictions on the singularities of the fibre. We present the ordinary and equivariant homologies as modules over the cohomology of the base, identify the…

Algebraic Geometry · Mathematics 2025-12-08 Francesca Carocci , Leonid Monin , Navid Nabijou

We give two generalizations of the Atiyah-Bott-Berline-Vergne localization theorem for the equivariant cohomology of a torus action: 1) replacing the torus action by a compact connected Lie group action, 2) replacing the manifold having a…

Differential Geometry · Mathematics 2014-01-23 Andres Pedroza , Loring Tu