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Related papers: Extending structures for Lie bialgebras

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We view disentanglement learning as discovering an underlying structure that equivariantly reflects the factorized variations shown in data. Traditionally, such a structure is fixed to be a vector space with data variations represented by…

Machine Learning · Computer Science 2021-06-08 Xinqi Zhu , Chang Xu , Dacheng Tao

It is known that Hochschild cohomology groups are represented by crossed extensions of associative algebras. In this paper, we introduce crossed $n$-fold extensions of a Lie algebra $\mathfrak{g}$ by a module $M$, for $n \geq 2$. The…

Rings and Algebras · Mathematics 2018-12-31 Apurba Das

The concept of weighted infinitesimal bialgebras provides an algebraic framework for understanding the non-homogeneous associative Yang-Baxter equation. In this paper, we endow the space of decorated planar rooted forests with a…

Combinatorics · Mathematics 2025-10-15 Loïc Foissy , Yunzhou Xie , Dawei Zhang , Yi Zhang

In the present paper we study abelian extensions of connected Lie groups $G$ modeled on locally convex spaces by smooth $G$-modules $A$. We parametrize the extension classes by a suitable cohomology group $H^2_s(G,A)$ defined by locally…

Group Theory · Mathematics 2007-05-23 Karl-Hermann Neeb

This is the central article of a series of three papers on cross product bialgebras. We present a universal theory of bialgebra factorizations (or cross product bialgebras) with cocycles and dual cocycles. We also provide an equivalent…

Quantum Algebra · Mathematics 2009-09-25 Yuri Bespalov , Bernhard Drabant

The present paper contains a systematic study of the structure of metric Lie algebras, i.e., finite-dimensional real Lie algebras equipped with a non-degenerate invariant symmetric bilinear form. We show that any metric Lie algebra without…

Differential Geometry · Mathematics 2007-05-23 Ines Kath , Martin Olbrich

We review (non-abelian) extensions of a given Lie algebra, identify a 3-dimensional cohomological obstruction to the existence of extensions. A striking analogy to the setting of covariant exterior derivatives, curvature, and the Bianchi…

Differential Geometry · Mathematics 2007-05-23 Dmitri Alekseevsky , Peter W. Michor , Wolfgang Ruppert

This PhD Thesis consists of two parts. The first part focuses on novel algebraic and geometric approaches to the classification problem of coboundary Lie bialgebras up to Lie algebra automorphisms. More specifically, Grassmann, graded…

Mathematical Physics · Physics 2026-01-01 Daniel Wysocki

In this series of two papers we will generalise the concept of extending a Lie algebroid by a Lie algebra bundle, leading to a notion of extending a Lie algebroid by another Lie algebroid whose orbits lie in the orbits of the former…

Differential Geometry · Mathematics 2026-03-30 Simon-Raphael Fischer

The coefficient algebra of a finite-dimensional Lie algebra on a finite-dimensional representation is defined as the subalgebra generated by all coefficients of the corresponding characteristic polynomial. We explore connections between…

Commutative Algebra · Mathematics 2025-11-14 Yin Chen , Runxuan Zhang

In this paper, we give a purely cohomological interpretation of the extension problem for (super) Lie algebras; that is the problem of extending a Lie algebra by another Lie algebra. We then give a similar interpretation of infinitesimal…

Representation Theory · Mathematics 2007-05-23 Alice Fialowski , Michael Penkava

The purpose of this paper is to establish a connection between various subjects such as dynamical r-matrices, Lie bialgebroids, and Lagrangian subalgebras. Our method relies on the theory of Dirac structures developed in dg-ga/9508013 and…

Differential Geometry · Mathematics 2007-05-23 Zhang-Ju Liu , Ping Xu

Let G be a connected semisimple algebraic group over $k$, with Lie algebra $\g$. Let $\h$ be a subalgebra of $\g$. A simple finite-dimensional $\g$-module V is said to be $\h$-indecomposable if it cannot be written as a direct sum of two…

Representation Theory · Mathematics 2017-10-18 Dmitri I. Panyushev

Given a finite-dimensional reductive Lie algebra $\mathfrak{g}$ equipped with a nondegenerate, invariant, symmetric bilinear form $B$, let $V^k(\mathfrak{g},B)$ denote the universal affine vertex algebra associated to $\mathfrak{g}$ and $B$…

Representation Theory · Mathematics 2020-05-13 Thomas Creutzig , Andrew R. Linshaw

Let $A \subseteq E$ be an extension of Hopf algebras such that there exists a normal left $A$-module coalgebra map $\pi : E \to A$ that splits the inclusion. We shall describe the set of all coquasitriangular structures on the Hopf algebra…

Quantum Algebra · Mathematics 2014-02-24 A. L. Agore

We study the skew-symmetric prolongation of a Lie subalgebra $\g \subseteq \mathfrak{so}(n)$, in other words the intersection $\Lambda^3 \cap (\Lambda^1 \otimes \g)$.We compute this space in full generality. Applications include uniqueness…

Differential Geometry · Mathematics 2012-08-08 Paul-Andi Nagy

In this paper we generalize classical results on Lie algebras and universal enveloping algebras of Lie algebras to Lie-Rinehart algebras. We define for any Lie-Rinehart algebra $L$ and any cocycle $f$ in $Z^2(L,B)$, a universal enveloping…

Algebraic Geometry · Mathematics 2020-11-13 Helge Øystein Maakestad

In this paper, we define (cohomologically) 1-shifted Manin triples and 1-shifted Lie bialgebras, and study their properties. We derive many results that are parallel to those found in ordinary Lie bialgebras, including the double…

Quantum Algebra · Mathematics 2025-03-13 Wenjun Niu , Victor Py

We study surjective homomorphisms f:\prod_I A_i\to B of not-necessarily-associative algebras over a commutative ring k, for I a generally infinite set; especially when k is a field and B is countable-dimensional over k. Our results have the…

Rings and Algebras · Mathematics 2013-05-10 George M. Bergman , Nazih Nahlus

We consider pairs of Lie algebras $g$ and $\bar{g}$, defined over a common vector space, where the Lie brackets of $g$ and $\bar{g}$ are related via a post-Lie algebra structure. The latter can be extended to the Lie enveloping algebra…

Numerical Analysis · Mathematics 2015-06-30 Kurusch Ebrahimi-Fard , Alexander Lundervold , Hans Munthe-Kaas