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In the study of NIL-affine actions on nilpotent Lie groups we introduced so called LR-structures on Lie algebras. The aim of this paper is to consider the existence question of LR-structures, and to start a structure theory of LR-algebras.…

Rings and Algebras · Mathematics 2008-01-09 Dietrich Burde , Karel Dekimpe , Sandra Deschamps

Let A be a finite dimensional unital associative algebra over a field K, which is also equipped with a coassociative counital coalgebra structure (\Delta,\eps). A is called a Weak Bialgebra if the coproduct \Delta is multiplicative. We do…

Quantum Algebra · Mathematics 2007-05-23 Florian Nill

In this paper we classify, up to equivalence, all semisimple nontrivial Hopf algebras of dimension $2^{2n+1}$ for $n\geq 2$ over an algebraically closed field of characteristic $0$ with the group of group-like elements isomorphic to…

Rings and Algebras · Mathematics 2015-10-12 Yevgenia Kashina

Using a connection to lozenge tilings of triangular regions, we establish an easily checkable criterion that guarantees the weak Lefschetz property of a quotient by a monomial ideal. It is also shown that each such ideal also has a…

Commutative Algebra · Mathematics 2016-06-07 David Cook , Uwe Nagel

In this paper, the main objective is to compare the abelian subalgebras and ideals of maximal dimension for finite-dimensional supersolvable Lie algebras. We characterise the maximal abelian subalgebras of solvable Lie algebras and study…

Rings and Algebras · Mathematics 2013-06-06 Manuel Ceballos , David A. Towers

Let H be a cosemisimple Hopf algebra over an algebraically closed field k which contains a simple subcoalgebra of dimension 9. We show that if H has no simple subcoalgebras of even dimension then H contains either a grouplike element with…

Rings and Algebras · Mathematics 2010-10-05 S. Burciu

Given a pair of nilpotent orbits in a simple Lie algebra, one can associate a pair of vertex algebras called affine W-algebras. Under some compatibility conditions on these orbits, we prove that one of these W-algebras can be obtained as…

Representation Theory · Mathematics 2025-01-09 Naoki Genra , Thibault Juillard

For every field $F$ which has a quadratic extension $E$ we show there are non-metabelian infinite-dimensional thin graded Lie algebras all of whose homogeneous components, except the second one, have dimension $2$. We construct such Lie…

Rings and Algebras · Mathematics 2021-01-29 M. Avitabile , A. Caranti , N. Gavioli , V. Monti , M. F. Newman , E. A. O'Brien

We use the methods of \cite{BM} to give a classification of $7-$dimensional minimal algebras, generated in degree 1, over any field $\bk$ of characteristic $\textrm{char}(\bk)\neq 2$, whose characteristic filtration has length 2.…

Algebraic Topology · Mathematics 2012-04-03 Giovanni Bazzoni

In this article, we introduce a category of weak Lie 3-algebras with suitable weak morphisms. The definition is based on the construction of a partial resolution over $\mathbb{Z}$ of the Koszul dual cooperad of the $\textrm{Lie}$ operad,…

Quantum Algebra · Mathematics 2017-10-31 Malte Dehling

The Schur-index of the $(A_1, X_n)$-Argyres-Douglas theory is conjecturally a character of a vertex operator algebra. Here such vertex algebras are found for the $A_{\text{odd}}$ and $D_{\text{even}}$-type Argyres-Douglas theories. The…

High Energy Physics - Theory · Physics 2017-01-24 Thomas Creutzig

We construct finite-dimensional Hopf algebras whose coradical is the group algebra of a central extension of an abelian group. They fall into families associated to a semisimple Lie algebra together with a Dynkin diagram automorphism. We…

Quantum Algebra · Mathematics 2022-06-23 Iván Angiono , Simon Lentner , Guillermo Sanmarco

We investigate the class of finite dimensional not necessary associative algebras that have slowly growing length, that is, for any algebra in this class its length is less than or equal to its dimension. We show that this class is…

Rings and Algebras · Mathematics 2022-03-09 Alexander Guterman , Dmitry Kudryavtsev

In this paper we study higher level Deligne--Lusztig representations of reductive groups over discrete valuation rings, with finite residue field $\mathbb{F}_q$. In previous work we proved that, at even levels, these geometrically…

Representation Theory · Mathematics 2023-11-10 Zhe Chen , Alexander Stasinski

In the Euclidean setting the Sobolev spaces $W^{\alpha,p}\cap L^\infty$ are algebras for the pointwise product when $\alpha>0$ and $p\in(1,\infty)$. This property has recently been extended to a variety of geometric settings. We produce a…

Functional Analysis · Mathematics 2016-05-16 Thierry Coulhon , Luke G. Rogers

We study the structure of the category of integrable level zero representations with finite dimensional weight spaces of affine Lie algebras. We show that this category possesses a weaker version of the finite length property, namely that…

Representation Theory · Mathematics 2008-08-12 Vyjayanthi Chari , Jacob Greenstein

We provide examples of finitely generated noetherian PI algebras for which there is no finite dimensional filtration with a noetherian associated graded ring; thus we answer negatively a question raised by M. Lorenz.

Rings and Algebras · Mathematics 2007-05-23 J. T. Stafford , J. J. Zhang

We apply the theory of finite dimensional weak C^*-Hopf algebras A as developed by G. B\"ohm, F. Nill and K. Szlach\'anyi to study reducible inclusion triples of von-Neumann algebras N \subset M \subset (M\cros\A). Here M is an A-module…

Quantum Algebra · Mathematics 2007-05-23 Florian Nill , Kornel Szlachanyi , Hans-Werner Wiesbrock

Let L be a finite-dimensional simple Lie algebra over an algebraically closed field of F characteristic p>3. We prove that if the p-envelope of L in the derivation algebra of L contains nonstandard tori of maximal dimension, then p=5 and L…

Representation Theory · Mathematics 2008-08-11 Alexander Premet , Helmut Strade

For any finitely generated abelian group $Q$, we reduce the problem of classification of $Q$-graded simple Lie algebras over an algebraically closed field of "good" characteristic to the problem of classification of gradings on simple Lie…

Representation Theory · Mathematics 2016-11-29 Volodymyr Mazorchuk , Kaiming Zhao