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Related papers: Algebraic representations of von Neumann algebras

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The set of normalizers between von Neumann (or, more generally, reflexive) algebras A and B, (that is, the set of all operators x such that xAx* is a subset of B and x*Bx is a subset of A) possesses `local linear structure': it is a union…

Operator Algebras · Mathematics 2022-06-29 A. Katavolos , I. G. Todorov

A 2-Hilbert space is a category with structures and properties analogous to those of a Hilbert space. More precisely, we define a 2-Hilbert space to be an abelian category enriched over Hilb with a *-structure, conjugate-linear on the…

q-alg · Mathematics 2008-02-03 John C. Baez

The polynomial deformations of the Witten extensions of the U(su(2)) and U(osp(1,2)) algebras are three generator algebras with normal ordering, admitting a two generator subalgebra. The modules and the representations of these algebras are…

q-alg · Mathematics 2008-02-03 Dennis Bonatsos , C. Daskaloyannis , P. Kolokotronis , D. Lenis

A notion of partial ideal for an operator algebra is a weakening the notion of ideal where the defining algebraic conditions are enforced only in the commutative subalgebras. We show that, in a von Neumann algebra, the ultraweakly closed…

Operator Algebras · Mathematics 2014-08-07 Nadish de Silva , Rui Soares Barbosa

We obtain a functional model for an arbitrary Abelian locally von Neumann algebra acting on a representing locally Hilbert space under the assumption that the index directed set is countable, in terms of locally essentially bounded…

Functional Analysis · Mathematics 2026-05-13 Aurelian Gheondea , Chaitanya J. Kulkarni , Santhosh Kumar Pamula

In this paper, we introduce the concepts of representation and dual representation for averaging Leibniz algebras. We also develop a cohomology theory for these algebras. Additionally, we explore the infinitesimal and formal deformation…

Rings and Algebras · Mathematics 2025-12-11 Bouzid Mosbahi , Imed Basdouri , Jean Lerbet

Regular normalized $B(W_1,W_2)$-valued non-negative spectral measures introduced in \cite{Zalar2014} are in one-to-one correspondence with unital $\ast$-representations $\rho:C(X,\mathbb{C})\otimes W_1 \rightarrow W_2$, where $X$ stands for…

Operator Algebras · Mathematics 2015-04-21 Aljaž Zalar

The basic mathematical framework for super Hilbert spaces over a Grassmann algebra with a Grassmann number-valued inner product is formulated. Super Hilbert spaces over infinitely generated Grassmann algebras arise in the functional…

Mathematical Physics · Physics 2009-10-31 Oliver Rudolph

We construct classes of von Neumann algebra modules by considering ``column sums" of noncommutative L^p spaces. Our abstract characterization is based on an L^{p/2}-valued inner product, thereby generalizing Hilbert C*-modules and…

Operator Algebras · Mathematics 2007-05-23 Marius Junge , David Sherman

We observe that for a large class of non-amenable groups $G$, one can find bounded representations of $A(G)$ on Hilbert space which are not completely bounded. We also consider restriction algebras obtained from $A(G)$, equipped with the…

Functional Analysis · Mathematics 2013-04-19 Yemon Choi , Ebrahim Samei

In the 1970s, Feldman and Moore classified separably acting von Neumann algebras containing Cartan MASAs using measured equivalence relations and 2-cocycles on such equivalence relations. In this paper, we give a new classification in terms…

Operator Algebras · Mathematics 2014-11-27 Allan P. Donsig , Adam H. Fuller , David R. Pitts

Let $\Gamma$ be a finite subgroup of $\SL_2(\C)$. We consider $\Gamma$-fixed point sets in Hilbert schemes of points on the affine plane $\C^2$. The direct sum of homology groups of components has a structure of a representation of the…

Quantum Algebra · Mathematics 2007-05-23 Hiraku Nakajima

We show that the irreducible components of any moduli space of semistable representations of a special biserial algebra are always isomorphic to products of projective spaces of various dimensions. This is done by showing that irreducible…

Representation Theory · Mathematics 2020-03-03 Andrew T. Carroll , Calin Chindris , Ryan Kinser , Jerzy Weyman

We study a class of algebras with non-Lie commutation relations whose symplectic leaves are surfaces of revolution: a cylinder or a torus. Over each of such surfaces we introduce a family of complex structures and Hilbert spaces of…

Quantum Algebra · Mathematics 2007-05-23 M. V. Karasev , E. M. Novikova

We extend some results of group representation theory and von Neumann algebras to the quaternionic Hilbert space case, proving the double commutant theorem (whose quaternionic proof requires a different procedure) and extend to the…

Mathematical Physics · Physics 2018-11-26 Valter Moretti , Marco Oppio

We study the structure of weakly-closed nonself-adjoint algebras arising from representations of single vertex 2-graphs. These are the algebras generated by 2 isometric tuples which satisfy a certain commutation relation. We show that these…

Operator Algebras · Mathematics 2015-04-01 Adam H. Fuller , Dilian Yang

The theory of non symmetric Dirichlet forms is generalized to the non abelian setting, also establishing the natural correspondences among Dirichlet forms, sub-Markovian semigroups and sub-Markovian resolvents within this context. Examples…

funct-an · Mathematics 2008-02-03 D. Guido , T. Isola , S. Scarlatti

We establish relations between representation dimensions of two algebras connected by a Frobenius bimodule or extension. Consequently, upper bounds and equality formulas for representation dimensions of group algebras, symmetric separably…

Representation Theory · Mathematics 2020-08-13 Changchang Xi

The Grothendieck groups of the categories of finitely generated modules and finitely generated projective modules over a tower of algebras can be endowed with (co)algebra structures that, in many cases of interest, give rise to a dual pair…

Representation Theory · Mathematics 2014-10-24 Alistair Savage , Oded Yacobi

Position deformation of a Heisenberg algebra and Hilbert space representation of both maximal length and minimal momentum uncertainties may lead to loss of Hermiticity of some operators that generate this algebra. Consequently, the…

Mathematical Physics · Physics 2025-09-30 Thomas Katsekpor , Latévi M. Lawson , Prince K. Osei , Ibrahim Nonkané