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(Finite) presentations of the Albert-Frank-Shalev Lie algebras

Claretta Carrara (2001)

Bollettino dell'Unione Matematica Italiana

In questo lavoro vengono studiate le algebre di Albert-Frank-Shalev. Queste sono algebre di Lie modulari di dimensione infinita, ottenute da un loop di certe algebre semplici di dimensione finita. Si dimostra che le algebre di Albert-Frank-Shalev sono unicamente determinate, a meno di elementi centrali o secondo centrali, da un certo quoziente finito-dimensionale. Tale risultato si ottiene dando la presentazione finita di un'algebra il cui quoziente sul secondo centro (infinito-dimensionale) è isomorfo...

Heisenberg algebra and a graphical calculus

Mikhail Khovanov (2014)

Fundamenta Mathematicae

A new calculus of planar diagrams involving diagrammatics for biadjoint functors and degenerate affine Hecke algebras is introduced. The calculus leads to an additive monoidal category whose Grothendieck ring contains an integral form of the Heisenberg algebra in infinitely many variables. We construct bases of the vector spaces of morphisms between products of generating objects in this category.

Holomorphic automorphisms and collective compactness in J*-algebras of operator

José Isidro (2007)

Open Mathematics

Let G be the Banach-Lie group of all holomorphic automorphisms of the open unit ball B 𝔄 in a J*-algebra 𝔄 of operators. Let 𝔉 be the family of all collectively compact subsets W contained in B 𝔄 . We show that the subgroup F ⊂ G of all those g ∈ G that preserve the family 𝔉 is a closed Lie subgroup of G and characterize its Banach-Lie algebra. We make a detailed study of F when 𝔄 is a Cartan factor.

Infinite-dimensional hyperkähler manifolds associated with Hermitian-symmetric affine coadjoint orbits

Alice Barbara Tumpach (2009)

Annales de l’institut Fourier

In this paper, we construct a hyperkähler structure on the complexification 𝒪 of any Hermitian symmetric affine coadjoint orbit 𝒪 of a semi-simple L * -group of compact type, which is compatible with the complex symplectic form of Kirillov-Kostant-Souriau and restricts to the Kähler structure of 𝒪 . By a relevant identification of the complex orbit 𝒪 with the cotangent space T 𝒪 of 𝒪 induced by Mostow’s decomposition theorem, this leads to the existence of a hyperkähler structure on T 𝒪 compatible with...

Invariant theory and the 𝒲 1 + algebra with negative integral central charge

Andrew Linshaw (2011)

Journal of the European Mathematical Society

The vertex algebra 𝒲 1 + , c with central charge c may be defined as a module over the universal central extension of the Lie algebra of differential operators on the circle. For an integer n 1 , it was conjectured in the physics literature that 𝒲 1 + , - n should have a minimal strong generating set consisting of n 2 + 2 n elements. Using a free field realization of 𝒲 1 + , - n due to Kac–Radul, together with a deformed version of Weyl’s first and second fundamental theorems of invariant theory for the standard representation of GL n ,...

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