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Related papers: The $\kappa$-Poincar\'e Group on a $C^*$-level

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Poincar\'e profiles are a family of analytically defined coarse invariants, which can be used as obstructions to the existence of coarse embeddings between metric spaces. In this paper we calculate the Poincar\'e profiles of all connected…

Group Theory · Mathematics 2025-05-14 David Hume , John M. Mackay , Romain Tessera

We associate to a pseudomanifold $X$ with isolated singularities a differentiable groupoid $G$ which plays the role of the tangent space of $X$. We construct a Dirac element $D$ and a Dual Dirac element $\lambda$ such that $D$ and $\lambda$…

Operator Algebras · Mathematics 2007-05-23 C. Debord , J. M. Lescure

Let $C^*$-algebra that is acted upon by a compact abelian group. We show that if the fixed-point algebra of the action contains a Cartan subalgebra $D$ satisfying an appropriate regularity condition, then $A$ is the reduced $C^*$-algebra of…

Operator Algebras · Mathematics 2019-09-12 Jonathan Brown , Adam Fuller , David Pitts , Sarah Reznikoff

We compute the second (and the first) cohomology groups of $^*$-algebras associated to the universal quantum unitary groups of not neccesarily Kac type, extending our earlier results for the free unitary group $U_d^+$. The extended setup…

Quantum Algebra · Mathematics 2023-06-22 Biswarup Das , Uwe Franz , Anna Kula , Adam Skalski

We obtain partial affirmative answers to the question whether isomorphism of the unitary groups of two C*-algebras, either as topological groups or as discrete groups, implies isomorphism of the C*-algebras as real C*-algebras.

Operator Algebras · Mathematics 2023-06-29 Lionel Fogang Takoutsing , Leonel Robert

Certain $*$-semigroups are associated with the universal $C^*$-algebra generated by a partial isometry, which is itself the universal $C^*$-algebra of a $*$-semigroup. A fundamental role for a $*$-structure on a semigroup is emphasized, and…

Operator Algebras · Mathematics 2014-06-03 Berndt Brenken

In this paper we construct compact forms associated with a complex Lie supergroup with Lie superalgebra of classical type.

Representation Theory · Mathematics 2014-01-30 R. Fioresi

We describe the envelope C*-algebra associated to a partial action of a countable discrete group on a locally compact space as a groupoid C*-algebra (more precisely as a C*-algebra from an equivalence relation) and we use our approach to…

Operator Algebras · Mathematics 2008-06-20 R. Exel , T. Giordano , D. Goncalves

We prove the existence of a strict deformation quantization for the canonical Poisson structure on the dual of an integrable Lie algebroid. It follows that any Lie groupoid C*-algebra may be regarded as a result of a quantization procedure.…

Mathematical Physics · Physics 2007-05-23 N. P. Landsman , B. Ramazan

This paper is concerned with the structures introduced recently by the authors of the current paper concerning the multiplier Hopf $*$-graph algebras and also the Cuntz-Krieger algebras and their relations with the $C^*$-graph algebras, and…

Quantum Algebra · Mathematics 2025-02-04 Farrokh Razavinia

Let $A$ be a unital $C^*$-algebra and $X$ an invulutive $A-A$-equivalence bimodule. Let $A\subset C_X$ be the unital inclusion of unital $C^*$-algebras induced by $X$. We suppose that $A' \cap C_X =\mathbf{C} 1$. We shall compute the Picard…

Operator Algebras · Mathematics 2020-06-25 Kazunori Kodaka

The dimension of the third homogeneous component of a matrix quantum bialgebra, determined by pair of quantum spaces, is calculated. The Poincar\'{e} series of some deformations of $GL(n)$ is calculated. A new deformation of $GL(3)$ with…

High Energy Physics - Theory · Physics 2008-02-03 Phung Ho Hai

For a large class of word hyperbolic groups G the cross product C^*-algebra arising from the action of G on its Gromov boundary is shown to satisfy Poincare duality in K-theory. This class strictly contains fundamental groups of compact,…

Operator Algebras · Mathematics 2016-09-07 Heath Emerson

Inspired by the commutator and anticommutator algebras derived from algebras graded by groups, we introduce noncommutatively graded algebras. We generalize various classical graded results to the noncommutatively graded situation concerning…

Rings and Algebras · Mathematics 2017-11-01 Patrik Nystedt

A bicovariant calculus of differential operators on a quantum group is constructed in a natural way, using invariant maps from \fun\ to \uqg\ , given by elements of the pure braid group. These operators --- the `reflection matrix' $Y \equiv…

High Energy Physics - Theory · Physics 2009-10-22 Peter Schupp , Paul Watts , Bruno Zumino

We introduce and investigate some examples of C$^*$-algebras which are related to multiplication maps in the ring of $p$-adic integers. We find ideals within these algebras and use the corresponding short exact sequences to compute the…

Operator Algebras · Mathematics 2023-12-18 Shelley Hebert , Slawomir Klimek , Matt McBride , J. Wilson Peoples

The complex exponential function is a local homeomorphism and gives therefore rise to an 'etale groupoid and a C*-algebra. We determine this algebra, as well as the alge bra of the complex conjugate of the exponential function.

Operator Algebras · Mathematics 2011-09-26 Klaus Thomsen

We construct the induced representations of the null-plane quantum Poincar\'e and quantum kappa Galilei algebras in (1+1) dimensions. The induction procedure makes use of the concept of module and is based on the existence of a pair of Hopf…

Quantum Algebra · Mathematics 2011-09-22 O. Arratia , M. A. del Olmo

We study the structure and dynamics of the infinite sequence of extensions of the Poincar{\'e} algebra whose method of construction was described in a previous paper [1]. We give explicitly the Maurer-Cartan (MC) 1-forms of the extended Lie…

High Energy Physics - Theory · Physics 2009-12-15 Sotirios Bonanos , Joaquim Gomis

We study the universal C^*-algebras generated by n projections $p_1, >..., p_n$ subject to the relation $p_1+... p_n = \lambda 1$, $\lambda \in \mathbb R$. The questions of when these C^*-algebras are type I, nuclear or exact are…

Operator Algebras · Mathematics 2010-08-09 Tatiana Shulman