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A Lie algebra structure on variation vector fields along an immersed curve in a $2$-dimensional real space form is investigated. This Lie algebra particularized to plane curves is the cornerstone in order to define a Hamiltonian structure…

Differential Geometry · Mathematics 2015-06-19 José del Amor , Ángel Giménez , Pascual Lucas

We prove a formality theorem for algebraic objects internal to smooth complex varieties that are not compact but whose mixed Hodge structure has a certain purity property.

Algebraic Topology · Mathematics 2017-03-27 Geoffroy Horel

In this note, we prove an obstruction theorem for the existence of A infinite-structures over a commutative ring R on an algebra A associative up to homotopy, in terms of the Hochschild cohomology of the associative algebra H(A). The hidden…

Rings and Algebras · Mathematics 2011-10-12 Muriel Livernet

We investigate Lie bialgebra structures on simple Lie algebras of non-split type $A$. It turns out that there are several classes of such Lie bialgebra structures, and it is possible to classify some of them. The classification is obtained…

Quantum Algebra · Mathematics 2017-02-20 Seidon Alsaody , Alexander Stolin

Electromagnetic field is considered in the framework of Clifford algebra $\C_2$ over a field of complex numbers. It is shown here that a modulo 2 periodicity of complex Clifford algebras may be connected with electromagnetic field.

High Energy Physics - Theory · Physics 2007-05-23 Vadim V. Varlamov

We construct a tangent-obstruction theory for Azumaya algebras equipped with a quadratic pair. Under the assumption that either 2 is a global unit or the algebra is of degree 2, we show how the deformation theory of these objects reduces to…

Algebraic Geometry · Mathematics 2025-04-09 Eoin Mackall , Cameron Ruether

We study the characteristic map of algebraic oriented cohomology of complete spin-flags and the ideal of invariants of formal group algebra. As an application, we provide an annihilator of the torsion part of the $\gamma$-filtration.…

Algebraic Geometry · Mathematics 2015-08-05 Changlong Zhong

We compare the second adjoint and trivial Leibniz cohomology spaces of a Lie algebra to the usual ones by a very elementary approach. The comparison gives some conditions, which are easy to verify for a given Lie algebra, for deciding…

Quantum Algebra · Mathematics 2011-03-15 Alice Fialowski , Louis Magnin , Ashis Mandal

It is shown that for any morphism, i: g --> h, of Lie algebras the vector space underlying the Lie algebra h is canonically a g-homogeneous formal manifold with the action of g being highly nonlinear and twisted by Bernoulli numbers. This…

Quantum Algebra · Mathematics 2008-06-04 S. A. Merkulov

In part I we reduced the arithmetic (characteristic zero) version of the P \not \subseteq NP conjecture to the problem of showing that a variety associated with the complexity class NP cannot be embedded in the variety associated the…

Computational Complexity · Computer Science 2007-05-23 Ketan D Mulmuley , Milind Sohoni

This is a paper in a series that studies smooth relative Lie algebra homologies and cohomologies based on the theory of formal manifolds and formal Lie groups. In three previous papers, we introduce the notion of formal manifolds and study…

Differential Geometry · Mathematics 2025-01-22 Fulin Chen , Binyong Sun , Chuyun Wang

Given a finite-dimensional, complex simple Lie algebra we exhibit an integral form for the universal enveloping algebra of its map algebra, and an explicit integral basis for this integral form. We also produce explicit commutation formulas…

Representation Theory · Mathematics 2013-11-15 Samuel H. Chamberlin

We study a weak form of formality for differential graded algebras, called $A_3$-formality, for the cohomology of pro-p Demushkin groups at odd primes p. We show that the differential graded $\mathbb{F}_p$-algebras of continuous cochains of…

Group Theory · Mathematics 2026-01-23 Ambrus Pál , Gereon Quick

We compute low-degree cohomology of current Lie algebras extended over the 3-dimensional simple algebra, compute deformations of related semisimple Lie algebras, and apply these results to classification of simple Lie algebras of absolute…

Rings and Algebras · Mathematics 2018-05-02 Alexander Grishkov , Pasha Zusmanovich

We develop an obstruction theory for Hirsch extensions of cbba's with twisted coefficients. This leads to a variety of applications, including a structural theorem for minimal cbba's, a construction of relative minimal models with twisted…

Algebraic Topology · Mathematics 2026-05-28 Jiahao Hu

We study the structure of the $E_2$-term of the Rothenberg-Steenrod spectral sequence converging to the mod 3 cohomology of the classifying space of the compact, connected, simply connected, exceptional Lie group of rank 6.

Algebraic Topology · Mathematics 2012-01-27 Mamoru Mimura , Yuriko Sambe , Michishige Tezuka

We show that hyperplane sections of strongly formal manifolds inherit strong formality. In particular, this property holds for generalized complete intersections defined by positive line bundles with trivial first de Rham cohomology group.…

Differential Geometry · Mathematics 2026-04-15 Lapo Rubini

The ADE classification scheme is encountered in many areas of mathematics, most notably in the study of Lie algebras. Here such a scheme is shown to describe families of two-dimensional conformal field theories.

High Energy Physics - Theory · Physics 2009-11-18 Andrea Cappelli , Jean-Bernard Zuber

In this paper we prove some general results on Leibniz 2-cocycles for simple Leibniz algebras. Applying these results we establish the triviality of the second Leibniz cohomology for a simple Leibniz algebra with coefficients in itself,…

Rings and Algebras · Mathematics 2015-02-03 J. Q. Adashev , M. Ladra , B. A. Omirov

We prove a result of classification for germs of formal and convergent quasi-homogeneous foliations in C^2 with fixed separatrix. Basically, we prove that the analytical and formal class of such a foliation depend respectively only on the…

Dynamical Systems · Mathematics 2007-05-23 Y. Genzmer