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Related papers: $C^*$-algebras: The (Quantum) Path Less Traveled

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In this article, we will show that the category of quaternion vector spaces, the category of (both one-sided and two sided) quaternion Hilbert spaces and the category of quaternion $B^*$-algebras are equivalent to the category of real…

Operator Algebras · Mathematics 2019-05-01 Chi-Keung Ng

The main purpose of this paper is to construct *-representations from unbounded C$^*$-seminorms on partial *-algebras and to investigate their *-representations.

Mathematical Physics · Physics 2009-04-07 F. Bagarello , A. Inoue , C. Trapani

Representations of $C^*$-algebras are realized on section spaces of holomorphic homogeneous vector bundles. The corresponding section spaces are investigated by means of a new notion of reproducing kernel, suitable for dealing with…

Operator Algebras · Mathematics 2008-02-22 Daniel Beltita , Jose E. Gale

We study Banach $\widetilde{\mathbb C}$-algebras, i.e., complete ultra-pseudo-normed algebras over the ring $\widetilde{\mathbb C}$ of Colombeau generalized complex numbers. We develop a spectral theory in such algebras. We show by explicit…

Functional Analysis · Mathematics 2008-11-12 Hans Vernaeve

A theory of reduction of Lie-Jordan Banach algebras with respect to either a Jordan ideal or a Lie-Jordan subalgebra is presented. This theory is compared with the standard reduction of C*-algebras of observables of a quantum system in the…

Mathematical Physics · Physics 2015-06-04 F. Falceto , L. Ferro , A. Ibort , G. Marmo

We extend the Gelfand-Naimark duality of commutative C*-algebras, "A COMMUTATIVE C*-ALGEBRA -- A LOCALLY COMPACT HAUSDORFF SPACE" to "A C*-ALGEBRA--A QUOTIENT OF A LOCALLY COMPACT HAUSDORFF SPACE". Thus, a C*-algebra is isomorphic to the…

Operator Algebras · Mathematics 2007-05-23 Mukul S. Patel

We study representations of Banach algebras on reflexive Banach spaces. Algebras which admit such representations which are bounded below seem to be a good generalisation of Arens regular Banach algebras; this class includes dual Banach…

Functional Analysis · Mathematics 2010-03-16 Matthew Daws

To a graph $\Gamma$ one can associate a C^*-algebra $C^*(\Gamma)$ generated by isometries. Such $C^*$-algebras were studied recently by Crisp and Laca. They are a special case of the Toeplitz C^*-algebras $\mathcal{T}(G, P)$ associated to…

Operator Algebras · Mathematics 2007-11-07 Nikolay A. Ivanov

In this paper, we provide a representation of a certain class of C*-valued positive sesquilinear and linear maps on non-unital quasi *-algebras. Also, we illustrate our results on the concrete examples of non-unital Banach quasi *-algebras,…

Operator Algebras · Mathematics 2024-09-10 Stefan Ivkovic , Bogdan D. Djordjevic , Giorgia Bellomonte

We show that if $G$ is a second countable locally compact Hausdorff \'etale groupoid carrying a suitable cocycle $c:G\to\mathbb{Z}$, then the reduced $C^*$-algebra of $G$ can be realised naturally as the Cuntz-Pimsner algebra of a…

Operator Algebras · Mathematics 2018-04-19 Adam Rennie , David Robertson , Aidan Sims

We prove that C*-algebras which, as Banach spaces, are Grothendieck cannot be decomposed into a tensor product of two infinite-dimensional C*-algebras. By a result of Pfitzner, this class contains all von Neumann algebras and their…

Operator Algebras · Mathematics 2016-10-26 Tomasz Kania

Let X be a product system over a quasi-lattice ordered group. Under mild hypotheses, we associate to X a C*-algebra which is co-universal for injective Nica covariant Toeplitz representations of X which preserve the gauge coaction. Under…

Operator Algebras · Mathematics 2012-03-09 Toke Meier Carlsen , Nadia S. Larsen , Aidan Sims , Sean Vittadello

This work will be centered in commutative Banach subalgebras of the algebra of bounded linear operators defined on a Free Banach spaces of countable type. The main goal of this work wil be to formulate a representation theorem for these…

Functional Analysis · Mathematics 2017-07-25 José Aguayo , Miguel Nova , Jacqueline Ojeda

We construct a large class of morphisms, which we call partial morphisms, of groupoids that induce $*$-morphisms of maximal and minimal groupoid $C^*$-algebras. We show that the association of a groupoid to its maximal (minimal) groupoid…

Operator Algebras · Mathematics 2018-08-13 Kyle Austin , Atish Mitra

It is now well established that quantum tomography provides an alternative picture of quantum mechanics. It is common to introduce tomographic concepts starting with the Schrodinger-Dirac picture of quantum mechanics on Hilbert spaces. In…

Quantum Physics · Physics 2012-04-25 A. Ibort , V. I. Manko , G. Marmo , A. Simoni , F. Ventriglia

We discuss the notion of spectral synthesis for the setting of Quantum Harmonic Analysis. Using these concepts, we study subalgebras of the full Toeplitz algebra with certain invariant symbols and their commutators. In particular, we find a…

Functional Analysis · Mathematics 2023-11-23 Robert Fulsche , Miguel Angel Rodriguez Rodriguez

This note aims to highlight the link between representable functionals and derivations on a Banach quasi *-algebra, i.e. a mathematical structure that can be seen as the completion of a normed *-algebra in the case the multiplication is…

Functional Analysis · Mathematics 2018-09-06 Maria Stella Adamo

This paper introduces quantum circuit $C^*$-algebra net, which provides a connection between $C^*$-algebra nets proposed in classical machine learning and quantum circuits. Using $C^*$-algebra, a generalization of the space of complex…

Machine Learning · Computer Science 2024-04-10 Yuka Hashimoto , Ryuichiro Hataya

Let $X$ be a product system over a quasi-lattice ordered groupoid $(G,P)$. Under mild hypotheses, we associate to $X$ a $C^*$-algebra which is couniversal for injective Nica covariant Toeplitz representations of $X$ which preserve the gauge…

Operator Algebras · Mathematics 2024-01-10 Massoud Amini , Mahdi Moosazadeh

We obtain a condensed reconstruction of algebraic quantum theory, emphasizing its foundational aspects and algebraic structure. We obtain the $W^*$-algebra structure from elementary assumptions about observers and how they can observe…

Quantum Physics · Physics 2023-11-30 Bharath Ron