English
Related papers

Related papers: Exotic Spaltenstein varieties

200 papers

We study the singularities of the irreducible components of the Springer fiber over a nilpotent element N with N^2=0 in a Lie algebra of type A or D (the so-called two columns case). We use Frobenius splitting techniques to prove that these…

Algebraic Geometry · Mathematics 2013-01-18 Nicolas Perrin , Evgeny Smirnov

We show that there is an affine Schubert variety in the infinite dimensional partial Flag variety (associated to the two- step parabolic subgroup of the Kac-Moody group {\hat SL(n)}, corresponding to omitting {\alpha}_0,{\alpha}_d) which is…

Algebraic Geometry · Mathematics 2015-05-04 V. Lakshmibai

Let G be a connected reductive algebraic group. We prove that the string parametrization of a crystal basis for a finite dimensional irreducible representation of G extends to a natural valuation on the field of rational functions on the…

Algebraic Geometry · Mathematics 2015-11-04 Kiumars Kaveh

We explain an elementary topological construction of the Springer representation on the homology of (topological) Springer fibers of types C and D in the case of nilpotent endomorphisms with two Jordan blocks. The Weyl group and component…

Representation Theory · Mathematics 2021-10-26 Catharina Stroppel , Arik Wilbert

We establish the existence of a pair of exotic surfaces in a punctured $K3$ which remains exotic after one external stabilization and have diffeomorphic complements. A key ingredient in the proof is a vanishing theorem of the family…

Geometric Topology · Mathematics 2021-11-16 Jianfeng Lin , Anubhav Mukherjee

Selfdual representations of any group fall into two classes when they are irreducible: those which carry a symmetric bilinear form, and the others which carry an alternating bilinear form. The Langlands correspondence, which matches the…

Number Theory · Mathematics 2008-07-03 Dipendra Prasad , Dinakar Ramakrishnan

We obtain a series of new results on the problem of irreducibility of commuting varieties associated with symmetric pairs or, in other words, $Z_2$-graded simple Lie algebras. In particular, we present many examples of reducible commuting…

Algebraic Geometry · Mathematics 2019-05-01 Dmitri Panyushev , Oksana Yakimova

Let $\mathbf{G}$ be a connected reductive group over an algebraically closed field $\mathbb{F}$ of good characteristic, satisfying some mild conditions. In this paper we relate tilting objects in the heart of Bezrukavnikov's exotic…

Representation Theory · Mathematics 2016-07-01 Carl Mautner , Simon Riche

We extend a construction of Stipsicz-Szab\'{o} of infinitely many irreducible exotic smooth structures of some closed four-manifolds with even $b_2^+$ and fundamental group $\mathbb{Z}/2\mathbb{Z}$. We use the double node surgery and…

Geometric Topology · Mathematics 2024-10-17 Márton Beke , László Koltai , Sarah Zampa

Every irreducible odd dimensional representation of the $n$'th symmetric or hyperoctahedral group, when restricted to the $(n-1)$'th, has a unique irreducible odd-dimensional constituent. Furthermore, the subgraph induced by odd-dimensional…

Representation Theory · Mathematics 2021-12-07 Arvind Ayyer , Amritanshu Prasad , Steven Spallone

Kato developed an exotic Deligne-Langlands correspondence using a geometric model for the multiparameter affine Hecke algebra of type C, based on his exotic nilpotent cone. Achar-Henderson and Springer showed that this exotic nilpotent is…

Representation Theory · Mathematics 2026-02-03 Filippo Ambrosio , Giovanna Carnovale , Francesco Esposito , Neil Saunders , Lewis Topley

We study the geometry and topology of $\Delta$-Springer varieties associated with two-row partitions. These varieties were introduced in recent work by Griffin-Levinson-Woo to give a geometric realization of a symmetric function appearing…

Representation Theory · Mathematics 2025-09-03 Abel Lacabanne , Pedro Vaz , Arik Wilbert

Let V be a 2n dimensional vector space over an algebraically closed field of odd characteristic. Let G = GL(V) and H = Sp_{2n} be the symplectic group contained in G. We call X = G/H \times V the exotic symmetric space, since its…

Representation Theory · Mathematics 2013-02-27 Toshiaki Shoji , Karine Sorlin

We study in detail two row Springer fibres of even orthogonal type from an algebraic as well as topological point of view. We show that the irreducible components and their pairwise intersections are iterated P^1-bundles. Using results of…

Representation Theory · Mathematics 2019-08-15 Michael Ehrig , Catharina Stroppel

This paper offers a number of examples showing that in the case of two independent variables the uniform ellipticity of a linear system of differential equations with partial derivatives of the second order, which fulfills condition (3), do…

Analysis of PDEs · Mathematics 2024-06-03 F. Criado-Aldeanueva , N. Odishelidze , J. M. Sanchez , M. Khachidze

Consider cotangent bundles of exotic spheres, with their canonical symplectic structure. They admit automorphisms which preserve the part at infinity of one fibre, and which are analogous to the square of a Dehn twist. Pursuing that…

Symplectic Geometry · Mathematics 2015-05-27 Paul Seidel

By extending the method of semi-modules developed by de Jong, Oort, Viehmann and Hamacher, we introduce a stratification for the affne Deligne-Lusztig variety (in the affne Grassmannian) attached to attached to a minuscule cocharacter and a…

Algebraic Geometry · Mathematics 2021-08-05 Sian Nie

Let $D$ be the Auslander algebra of $\mathbb{C}[t]/(t^n)$, which is quasi-hereditary, and $\mathcal{F}_\Delta$ the subcategory of good $D$-modules. For any $\mathsf{J}\subseteq[1, n-1]$, we construct a subcategory…

Representation Theory · Mathematics 2026-05-25 Bernt Tore Jensen , Xiuping Su

We define several equivariant concordance invariants using knot Floer homology. We show that our invariants provide a lower bound for the equivariant slice genus and use this to give a family of strongly invertible slice knots whose…

Geometric Topology · Mathematics 2023-08-08 Irving Dai , Abhishek Mallick , Matthew Stoffregen

We investigate the representations of the exotic conformal Galilei algebra. This is done by explicitly constructing all singular vectors within the Verma modules, and then deducing irreducibility of the associated highest weight quotient…

Mathematical Physics · Physics 2015-05-20 Naruhiko Aizawa , Phillip S Isaac