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Related papers: SK1 for graded division algebras

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Let $R$ be a finite-dimensional algebra over an algebraically closed field $F$ graded by an arbitrary group $G$. We prove that $R$ is a graded division algebra if and only if it is isomorphic to a twisted group algebra of some finite…

Rings and Algebras · Mathematics 2007-05-23 Y. A. Bahturin , S. K. Sehgal , M. V. Zaicev

Graded Hecke algebras can be constructed geometrically, with constructible sheaves and equivariant cohomology. The input consists of a complex reductive group G (possibly disconnected) and a cuspidal local system on a nilpotent orbit for a…

Algebraic Geometry · Mathematics 2025-01-20 Maarten Solleveld

We classify, up to isomorphism and up to equivalence, division gradings (by abelian groups) on finite-dimensional simple real algebras. Gradings on finite-dimensional simple algebras are determined by division gradings, so our results give…

Rings and Algebras · Mathematics 2015-12-23 Adrián Rodrigo-Escudero

The classification, both up to isomorphism or up to equivalence, of the gradings on a finite dimensional nonassociative algebra A over an algebraically closed field F, such that its group scheme of automorphisms is smooth, is shown to be…

Rings and Algebras · Mathematics 2014-07-03 Alberto Elduque

For a Dedekind domain $R$ with field of fractions $K$ a classical $R$-order in a semisimple $K$-algebra $A$ is an $R$-projective $R$-subalgebra $\Lambda$ of $A$ such that $K\Lambda=A$. We study differential graded $K$-algebras which are…

Rings and Algebras · Mathematics 2024-09-12 Alexander Zimmermann

If the group of a 2-knot group $K$ has an abelian normal subgroup of rank $\geq1$ which is not finitely generated then either $K$ has no minimal Seifert hypersurface or $K$ is topologically equivalent to Example 10 of Ralph Fox's``{\it A…

Geometric Topology · Mathematics 2026-05-19 Jonathan A. Hillman

We prove some triviality results for reduced Whitehead groups and reduced unitary Whitehead groups for division algebras over a henselian discrete valuation field whose residue field has virtual cohomological dimension or separable…

Number Theory · Mathematics 2025-07-24 Yong Hu , Yisheng Tian

We first prove that the K-theoretic Hall algebra of a preprojective algebra of affine type is isomorphic to the positive half of a quantum toroidal quantum group. An essential step consists to deform the K-theoretic Hall algebra so that the…

Representation Theory · Mathematics 2022-03-30 Michela Varagnolo , Eric Vasserot

We prove that the torsion subgroup of the abelian fundamental group is finite for a regular geometrically integral projective variety over a local field. We also study the structure of $SK_1(X)$ for a regular projective variety $X$ over a…

Algebraic Geometry · Mathematics 2025-01-08 Rahul Gupta , Jitendra Rathore

We formalize some known categorical equivalences to give a rigorous treatment of smooth representations of p-adic general linear groups, as ungraded modules over quiver Hecke algebras of type A. Graded variants of RSK-standard modules are…

Representation Theory · Mathematics 2021-06-08 Maxim Gurevich

Given a field with a set of discrete valuations $V$, we show how the genus of a division algebra over the field is related to the genus of the residue algebras at various valuations in $V$ and the ramification data. When the division…

Number Theory · Mathematics 2024-09-24 S. Srimathy

In this paper we introduce the class of graded Poisson color algebras as the natural generalization of graded Poisson algebras and graded Poisson superalgebras. For $\Lambda$ an arbitrary abelian group, we show that any of such…

Mathematical Physics · Physics 2023-04-25 Valiollah Khalili

Let Wh^w(G) be the K_1-group of square matrices over the integral group ring ZG which are not necessarily invertible but induce weak isomorphisms after passing to Hilbert space completions. Let D(G) be the division closure of ZG in the…

K-Theory and Homology · Mathematics 2018-03-16 Peter Linnell , Wolfgang Lück

We define a class $\mathcal{U}$ of solvable groups of finite abelian section rank which includes all such groups that are virtually torsion-free as well as those that are finitely generated. Assume that $G$ is a group in $\mathcal{U}$ and…

Group Theory · Mathematics 2014-12-30 Karl Lorensen

We introduce the notion of a graded group action on a graded algebra or, which is the same, a group action by graded pseudoautomorphisms. An algebra with such an action is a natural generalization of an algebra with a super- or a…

Rings and Algebras · Mathematics 2025-05-22 A. S. Gordienko

Though the uniformization theorem guarantees an equivalence of Riemann surfaces and smooth algebraic curves, moving between analytic and algebraic representations is inherently transcendental. Our analytic curves identify pairs of circles…

Geometric Topology · Mathematics 2024-01-26 Samantha Fairchild , Ángel David Ríos Ortiz

We develop and collect techniques for determining Hochschild cohomology of skew group algebras S(V)#G and apply our results to graded Hecke algebras. We discuss the explicit computation of certain types of invariants under centralizer…

Rings and Algebras · Mathematics 2007-05-23 Anne V. Shepler , Sarah Witherspoon

We prove Cuntz-Krieger and graded uniqueness theorems for Steinberg algebras. We also show that a Steinberg algebra is basically simple if and only if its associated groupoid is both effective and minimal. Finally we use results of…

Rings and Algebras · Mathematics 2014-03-20 Lisa Orloff Clark , Cain Edie-Michell

We extend the classical notion of standardly stratified $k$-algebra (stated for finite dimensional $k$-algebras) to the more general class of rings, possibly without $1,$ with enough idempotents. We show that many of the fundamental…

Rings and Algebras · Mathematics 2020-09-03 O. Mendoza , M. Ortíz , C. Sáenz , V. Santiago

The aim of this paper is to study the group of isomorphism classes of torsors of finite flat group schemes of rank 2 over a commutative ring $R$. This, in particular, generalises the group of quadratic algebras (free or projective), which…

Algebraic Geometry · Mathematics 2019-02-20 Ilia Pirashvili