English
Related papers

Related papers: Fibres de Springer et jacobiennes compactifiees

200 papers

We extend a result of Yun on minimal reduction types to the parahoric case. This implies a uniqueness property for 2-special representations appearing in the cohomology of certain affine Springer fibers. Using this, we settle a conjecture…

Representation Theory · Mathematics 2025-04-08 Anlong Chua

We begin with a comprehensive discussion of the punctual Hilbert scheme of the regular two-dimensional local ring in terms of the Gr\"obner cells. These schemes are the most degenerate fibers of the Grothendieck-Deligne norm map (the…

Algebraic Geometry · Mathematics 2021-12-23 Ivan Cherednik

For the group $\mathrm{GL}_{n}$ and the anisotropic elements, we confirm the purity hypothesis of Goresky, Kottwitz and MacPherson, which states that the affine Springer fibers are cohomologically pure in the sense of Grothendieck-Deligne.

Algebraic Geometry · Mathematics 2026-05-27 Zongbin Chen

To every singular reduced projective curve X one can associate many fine compactified Jacobians, depending on the choice of a polarization on X, each of which yields a modular compactification of a disjoint union of the generalized Jacobian…

Algebraic Geometry · Mathematics 2017-05-09 Margarida Melo , Antonio Rapagnetta , Filippo Viviani

We provide an explicit presentation of the equivariant cohomology ring of the compactified Jacobian $J_{q/p}$ of the rational curve $C_{q/p}$ with planar equation $x^{q}=y^{p}$ for $(p,q)=1$. We also prove analogous results for the closely…

Algebraic Geometry · Mathematics 2017-10-17 Alexei Oblomkov , Zhiwei Yun

We study affine maps between affine manifolds. Even when the fibers are compact and diffeomorphic, two of them can inherit different affine structures from the source space. This leads to a fixed linear holonomy deformation theory of the…

Differential Geometry · Mathematics 2007-05-23 A. Tsemo

We construct a bijection between admissible representations for an affine Lie algebra $\mathfrak{g}$ at boundary admissible levels and $\mathbb{C}^\times$ fixed points in homogeneous elliptic affine Springer fibres for the Langlands dual…

Representation Theory · Mathematics 2024-04-03 Peng Shan , Dan Xie , Wenbin Yan

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

We prove that if $X$ and $S$ are smooth varieties and $f\colon X\to S$ is an elliptic fibration with singular fibers curves of types I$_N$ with $N\geq 1$, II, III and IV, then the relative Jacobian $\hat{f}\colon \bar{M}_{X/S}\to S$ of $f$,…

Algebraic Geometry · Mathematics 2007-05-23 Ana Cristina Lopez

We develop a theory of singular support for various infinite dimensional stacks and establish several functoriality properties. Then we apply this theory to compute the singular support of the Grothendieck-Springer affine Springer sheaf and…

Algebraic Geometry · Mathematics 2023-12-12 Alexis Bouthier

This is the first paper of a series of three. Here we give an abstract definition of the relative compactified Jacobian of a family of reduced curves. We prove that, under some mild assumptions on the family of curves, the fibres of the…

Algebraic Geometry · Mathematics 2025-05-14 Marco Fava , Nicola Pagani , Filippo Viviani

This paper constructs pavings by affine spaces for the affine Springer fibers for PGL(3) obtained from regular compact elements in a split maximal torus. These pavings are constructed by intersecting the affine Springer fiber with a…

Representation Theory · Mathematics 2007-05-23 Vincent Lucarelli

This paper studies two new kinds of affine Springer fibers that are adapted to the root valuation strata of Goresky-Kottwitz-MacPherson. In addition it develops various linear versions of Katz's Hodge-Newton decomposition.

Representation Theory · Mathematics 2010-03-11 Robert Kottwitz , Eva Viehmann

We prove that a 1-dimnl family of abelian varieties with an ample sheaf defining principal polarization can be canonically compactified (after a finite base change) to a projective family with an ample sheaf. We show that the central fiber…

alg-geom · Mathematics 2008-02-03 Valery Alexeev , Iku Nakamura

For any projective curve $X$ let $\bar{M}^d(X)$ be the Simpson moduli space of pure dimension one rank 1 degree $d$ sheaves that are semistable with respect to a fixed polarization $H$ on $X$. When $X$ is a reduced curve the connected…

Algebraic Geometry · Mathematics 2007-05-23 Ana Cristina Lopez

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

Topological properties of the jacobian curve ${\mathcal J}_{\mathcal{F},\mathcal{G}}$ of two foliations $\mathcal{F}$ and $\mathcal{G}$ are described in terms of invariants associated to the foliations. The main result gives a decomposition…

Dynamical Systems · Mathematics 2023-06-21 Nuria Corral

Let $A$ be an abelian variety and $G$ a finite group of automorphisms of $A$ fixing the origin such that $A/G$ is smooth. The quotient $A/G$ can be seen as a fibration over an abelian variety whose fibers are isomorphic to a product of…

Algebraic Geometry · Mathematics 2024-07-02 Gary Martinez-Nunez

We explicitly construct the algebraic model of affine Jacobian of a generic algebraic curve of high genus and use it to compute the Euler characteristic of the Jacobian and investigate its structure.

Mathematical Physics · Physics 2007-05-23 F. A. Smirnov , V. Zeitlin

We decompose the fibers of the Springer resolution for the odd nilcone of the Lie superalgebra $\osp(2n+1,2n)$ into locally closed subsets. We use this decomposition to prove that almost all fibers are connected. However, in contrast with…

Representation Theory · Mathematics 2010-03-01 Séverine Leidwanger , Nicolas Perrin