English
Related papers

Related papers: Witt vector affine Springer fibers

200 papers

We explain an algorithm to calculate Arthur's weighted orbital integral in terms of the number of rational points on the fundamental domain of the associated affine Springer fiber. The strategy is to count the number of rational points of…

Algebraic Geometry · Mathematics 2021-10-06 Zongbin Chen

The paper deals with two problems that seem to be of different nature: the local behavior of the weighted orbital integrals and the dependence of the affine Springer fibers on the root valuation datum of their defining elements. The…

Algebraic Geometry · Mathematics 2024-12-02 Zongbin Chen

This paper extends the affine Springer theory developed by Bouthier, Kazhdan, and the second author (see [BKV]) to the mixed characteristic case. In particular, we introduce a theory of perfectly placid perfect infinity stacks and establish…

Representation Theory · Mathematics 2026-01-16 Noam Nissan , Yakov Varshavsky

These are the expanded lecture notes from the author's mini-course during the graduate summer school of the Park City Math Institute in 2015. The main topics covered are: geometry of Springer fibers, affine Springer fibers and Hitchin…

Representation Theory · Mathematics 2016-02-04 Zhiwei Yun

This paper defines and studies a stratification of the adjoint quotient of the Lie algebra of a reductive group over a Laurent power series field. The stratification arises naturally in the context of affine Springer fibers.

Representation Theory · Mathematics 2007-05-23 Mark Goresky , Robert Kottwitz , Robert MacPherson

We establish a relation between the known parametrization of a family of irreducible representations of a Weyl group and Springer's correspondence. We outline a parametrization of unipotent character sheaves on a connected reductive group…

Representation Theory · Mathematics 2012-02-14 G. Lusztig

Following Goresky, Kottwitz and MacPherson, we compute the homology of truncated affine Springer fibers in the unramified case but under a purity assumption. We prove this assumption in the equivalued case. The truncation parameter is…

Algebraic Geometry · Mathematics 2007-05-23 Pierre-Henri Chaudouard , Gérard Laumon

Let X/S be a hyperelliptic curve of genus g over the spectrum of a discrete valuation ring. Two fundamental numerical invariants are attached to X/S: the valuation of the hyperelliptic discriminant of X/S, and the valuation of the Mumford…

Algebraic Geometry · Mathematics 2012-04-25 Robin de Jong

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 show that representations of convolution algebras such as Lustzig's graded affine Hecke algebra or the quiver Hecke algebra and quiver Schur algebra in (affine) type A can be realised in terms of certain equivariant motivic sheaves…

Representation Theory · Mathematics 2021-11-16 Jens Niklas Eberhardt , Catharina Stroppel

We give a concrete description of the category of etale algebras over the ring of Witt vectors of a given finite length with entries in an arbitrary ring. We do this not only for the classical p-typical and big Witt vector functors but also…

Algebraic Geometry · Mathematics 2015-12-15 James Borger

We classify the irreducible representations of smooth, connected affine algebraic groups over a field, by tackling the case of pseudo-reductive groups. We reduce the problem of calculating the dimension for pseudo-split pseudo-reductive…

Representation Theory · Mathematics 2019-11-19 Michael Bate , David I. Stewart

For G a semisimple algebraic group, we revisit the description of the components of the affne Springer fiber given by ts, with s a regular semisimple element. We then compute the fixed points of each component of a particular affne Springer…

Algebraic Geometry · Mathematics 2019-10-17 Pablo Boixeda Alvarez

Let G be a connected reductive group over an algebraically closed field and W be its Weyl group. Steinberg constructed a transversal slice of the regular unipotent orbit in G. This construction was generalized to n was generalized to…

Representation Theory · Mathematics 2024-12-25 Chengze Duan

We propose a generalization of Springer representations to the context of groups over a global function field. The global counterpart of the Grothendieck simultaneous resolution is the parabolic Hitchin fibration. We construct an action of…

Algebraic Geometry · Mathematics 2009-04-22 Zhiwei Yun

For the group $\mathrm{GL}_{d}$, we confirm a conjecture of Goresky, Kottwitz and MacPherson, which states that the cohomology of the affine Springer fibers depend only on the root valuation datum of their defining elements. The proof…

Algebraic Geometry · Mathematics 2024-04-15 Zongbin Chen

The ring of classic Witt vectors is a fundamental object in mixed characteristic commutative algebra which has many applications in number theory. There is a significant generalization due to Dress and Siebeneicher which for any profinite…

Commutative Algebra · Mathematics 2012-10-15 Lance Edward Miller

In this paper we prove a direct geometric relation between Deligne--Lusztig varieties and Springer fibres in type $\mathsf{A}$: For any rational unipotent element, the Springer fibre cuts out a unique component of a specific…

Representation Theory · Mathematics 2021-06-03 Zhe Chen

We give an explicit approach to quotienting affine varieties by linear actions of linear algebraic groups with graded unipotent radical, using results from projective Non-Reductive GIT. Our quotients come with explicit projective…

Algebraic Geometry · Mathematics 2024-04-11 Eloise Hamilton , Victoria Hoskins , Joshua Jackson

This paper concerns preprojective representations of a finite connected valued quiver without oriented cycles. For each such representation, an explicit formula in terms of the geometry of the quiver gives a unique, up to a certain…

Representation Theory · Mathematics 2007-05-23 Mark Kleiner , Helene R. Tyler