English
Related papers

Related papers: Affine Grassmannians for Triality Groups

200 papers

Affine hamiltonians are defined in the paper and their study is based especially on the fact that in the hyperregular case they are dual objects of lagrangians defined on affine bundles, by mean of natural Legendre maps. The variational…

Mathematical Physics · Physics 2013-01-01 Paul Popescu , Marcela Popescu

In this paper we show that an affine space is determined by the abstract group structure of its group of regular automorphisms in the category of connected affine varieties. To prove this we study commutative subgroups of the group of…

Algebraic Geometry · Mathematics 2022-03-17 Serge Cantat , Andriy Regeta , Junyi Xie

We extend the work of Pappas-Rapoport-Zhu on twisted affine Grassmannians to wildly ramified, quasi-split, and residually split groups, assuming the maximal torus is induced. This relies on the construction, inspired by Tits, of certain…

Algebraic Geometry · Mathematics 2021-02-04 João Lourenço

In this paper we study quasi-homogeneous affine algebraic varieties, that is, varieties obtained as closures of orbits of suitable group representations. We also discuss one interesting case that has links with the Orthogonal Grassmannian…

Algebraic Geometry · Mathematics 2015-06-16 Umar Hayat

The minimal degeneration singularities in the affine Grassmannians of simple simply-laced algebraic groups are determined to be either Kleinian singularities of type A, or closures of minimal orbits in nilpotent cones. The singularities for…

Algebraic Geometry · Mathematics 2007-05-23 Anton Malkin , Viktor Ostrik , Maxim Vybornov

Trinomial varieties are affine varieties given by a system of equations consisting of polynomials with three terms. Such varieties are total coordinate spaces of normal varieties with torus action of complexity one. For an affine variety…

Algebraic Geometry · Mathematics 2025-06-26 Mikhail Ignatev , Timofey Vilkin

The Grassmannian of affine subspaces is a natural generalization of both the Euclidean space, points being zero-dimensional affine subspaces, and the usual Grassmannian, linear subspaces being special cases of affine subspaces. We show…

Differential Geometry · Mathematics 2018-07-31 Lek-Heng Lim , Ken Sze-Wai Wong , Ke Ye

We consider a new class of linear codes, called affine Grassmann codes. These can be viewed as a variant of generalized Reed-Muller codes and are closely related to Grassmann codes. We determine the length, dimension, and the minimum…

Information Theory · Computer Science 2010-06-22 Peter Beelen , Sudhir R. Ghorpade , Tom Hoeholdt

We give a bijection between certain colored partitions and the elements in the quotient of an affine Weyl group modulo its Weyl group. By Bott's formula these colored partitions give rise to some partition identities. In certain types,…

Combinatorics · Mathematics 2008-09-28 Sara C. Billey , Stephen A. Mitchell

We prove that there exist finitely presented, residually finite groups that are profinitely rigid in the class of all finitely presented groups but not in the class of all finitely generated groups. These groups are of the form $\Gamma…

Group Theory · Mathematics 2025-04-15 M. R. Bridson , A. W. Reid , R. Spitler

This paper is devoted to a study of the automorphism groups of three series of finite dimensional special odd Hamiltonian superalgebras $\mathfrak{g}$ over a field of prime characteristic. Our aim is to characterize the connections between…

Rings and Algebras · Mathematics 2013-04-25 Liming Tang , Wende Liu

This is a survey on the automorphism groups in various classes of affine algebraic surfaces and the algebraic group actions on such surfaces. Being infinite-dimensional, these automorphism groups share some important features of algebraic…

Algebraic Geometry · Mathematics 2025-03-06 Sergei Kovalenko , Alexander Perepechko , Mikhail Zaidenberg

Trialitarian automorphisms are related to automorphisms of order 3 of the Dynkin diagram of type D4. Octic etale algebras with trivial discriminant, containing quartic subalgebras, are classified by Galois cohomology with value in the Weyl…

Rings and Algebras · Mathematics 2010-01-27 Max-Albert Knus , Jean-Pierre Tignol

We prove that certain Fuchsian triangle groups are profinitely rigid in the absolute sense, i.e. each is distinguished from all other finitely generated, residually finite groups by its set of finite quotients. We also develop a method…

Group Theory · Mathematics 2021-10-04 M. R. Bridson , D. B. McReynolds , A. W. Reid , R. Spitler

We introduce the notion of affine strict polynomial functor. We show how this concept helps to understand homological behavior of the operation of Frobenius twist in the category of strict polynomial functors over a field of positive…

K-Theory and Homology · Mathematics 2014-11-14 Marcin Chałupnik

We describe all the fine group gradings, up to equivalence, on the Lie algebra $\mathfrak d_4$. This problem is equivalent to finding the maximal abelian diagonalizable subgroups of the automorphism group of $\mathfrak d_4$. We prove that…

Rings and Algebras · Mathematics 2008-04-11 Cristina Draper , Cándido Martín , Antonio Viruel

In this paper we make an initial study on type D moduli spaces in positive characteristic $p\neq 2$, where we allow $p$ ramified in the definite quaternion algebra. We classify the isogeny classes of $p$-divisible groups with additional…

Number Theory · Mathematics 2020-06-04 Chia-Fu Yu

The real Grassmannian is both a projective variety (via Pl\"ucker coordinates) and an affine variety (via orthogonal projections). We connect these two representations, and we develop the commutative algebra of the latter variety. We…

Algebraic Geometry · Mathematics 2024-07-08 Karel Devriendt , Hannah Friedman , Bernhard Reinke , Bernd Sturmfels

We study the topological group structure (coming from loop multiplication) on an affine Grassmannian. In particular, we study finite-dimensional subvarieties that generate the homology ring. We show that there is a canonical family of…

Algebraic Topology · Mathematics 2008-10-21 Peter J. Littig , Stephen A. Mitchell

Affine structures on a Lie groupoid, including affine $k$-vector fields, $k$-forms and $(p,q)$-tensors are studied. We show that the space of affine structures is a 2-vector space over the space of multiplicative structures. Moreover, the…

Differential Geometry · Mathematics 2021-02-09 Honglei Lang , Zhangju Liu , Yunhe Sheng