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Related papers: Gelfand-Naimark Theorems for Ordered *-Algebras

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We give a spectral theorem for unital representations of Hermitian commutative unital *-algebras by possibly unbounded operators in a pre-Hilbert space. A better result is known for the case in which the *-algebra is countably generated.

Operator Algebras · Mathematics 2024-11-13 Marco Thill

Este art\'iculo presenta como resultado principal la equivalencia entre, las categor\'ias de espacios topol\'ogicos Hausdorff-Compactos y la categor\'ia de las $C^*-$\'algebras conmutativas con unidad, producto de la ``traducci\'on'' en…

Category Theory · Mathematics 2024-09-25 Sebastian Alvarez Avendaño , Breitner Ocampo , Pedro Rizzo

Given a group G, we construct, in a canonical way, an inverse semigroup S(G) associated to G. The actions of S(G) are shown to be in one-to-one correspondence with the partial actions of G, both in the case of actions on a set, and that of…

funct-an · Mathematics 2008-02-03 Ruy Exel

In this project, we will develop the theory of Banach algebras and prove two celebrated theorems, the Gelfand representation theorem and the GKZ theorem. We will then proceed to develop the theory of $C^*$-algebras and prove the…

Operator Algebras · Mathematics 2021-04-06 Senan Sekhon

We show that certain C*-algebras which have been studied among others by Arzumanian, Vershik, Deaconu, and Renault in connection to a measure preserving transformation of a measure space and/or to a covering map of a compact space are…

Operator Algebras · Mathematics 2007-05-23 R. Exel , A. Vershik

We introduce a new class of operator algebras -- tracially complete C*-algebras -- as a vehicle for transferring ideas and results between C*-algebras and their tracial von Neumann algebra completions. We obtain structure and classification…

Sufficient conditions for existence of a faithful representation of a *-algebra in terms of its G\"obner basis is presented. Proposed construction of faithful representation is applicable to concrete examples: *-doubles, monomial…

Operator Algebras · Mathematics 2007-05-23 Stanislav Popovych , Kyrylo Vynogradov

We present a constructive proof of the Stone-Yosida representation theorem for Riesz spaces motivated by considerations from formal topology. This theorem is used to derive a representation theorem for f-algebras. In turn, this theorem…

Functional Analysis · Mathematics 2008-08-21 Thierry Coquand , Bas Spitters

T*-categories are introduced as a ternary generalization of C*-categories. Their linking C*-categories are constructed and the Gelfand-Naimark representation theorems of Zettl for C*-ternary rings and for W*-ternary rings, are generalized…

Operator Algebras · Mathematics 2023-05-24 Robert Pluta , Bernard Russo

We consider positive semidefinite kernels valued in the $*$-algebra of adjointable operators on a VE-space (Vector Euclidean space) and that are invariant under actions of $*$-semigroups. A rather general dilation theorem is stated and…

Functional Analysis · Mathematics 2017-02-06 Serdar Ay , Aurelian Gheondea

We prove constructive versions of various usual results related to the Gelfand duality. Namely, that the constructive Gelfand duality extend to a duality between commutative nonunital C*-algebras and locally compact completely regular…

Category Theory · Mathematics 2015-02-04 Simon Henry

We establish a Gelfand-Naimark-Segal construction which yields a correspondence between cyclic unitary representations and positive definite superfunctions of a general class of $\mathbb Z_2^n$-graded Lie supergroups.

Mathematical Physics · Physics 2017-09-20 Mohammad Mohammadi , Hadi Salmasian

We introduce a category of stochastic maps (certain Markov kernels) on compact Hausdorff spaces, construct a stochastic analogue of the Gelfand spectrum functor, and prove a stochastic version of the commutative Gelfand-Naimark Theorem.…

Functional Analysis · Mathematics 2017-10-06 Arthur J. Parzygnat

It is shown that the *-algebra of all (closed densely defined linear) operators affiliated with a finite type I von Neumann algebra admits a unique center-valued trace, which turns out to be, in a sense, normal. It is also demonstrated that…

Operator Algebras · Mathematics 2017-05-26 Piotr Niemiec , Adam Wegert

We provide a complete description of the order isomorphisms between the self-adjoint parts of $C^*$-algebras. Furthermore, we characterize such isomorphisms between general operator intervals in $AW^*$-algebras. For the description, we use…

Operator Algebras · Mathematics 2026-01-22 Youssef El Khatiri

We prove that unital graph C*-algebras often admit a convenient decomposition into amalgamated free products. We use this to give a complete characterization of when a unital graph C*-algebra is residually finite-dimensional and when it is…

Operator Algebras · Mathematics 2026-03-05 Guillaume Bellier , Tatiana Shulman

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

We consider an abstract Wick ordering as a family of relations on elements a_i and define *-algebras by these relations. The relations are given by a fixed operator T:h\otimes h --> h \otimes h, where h is one-particle space, and they…

Quantum Algebra · Mathematics 2007-05-23 Palle E. T. Jorgensen , Daniil P. Proskurin , Yurii Samoilenko

C*-algebras form rather general and rich mathematical structures that can be studied with different morphisms (preserving multiplication, or not), and with different properties (commutative, or not). These various options can be used to…

Category Theory · Mathematics 2017-01-11 Robert W. J. Furber , Bart P. F. Jacobs

We give an order-theoretic characterization of the essential image of the forgetful functor from the category of real/complex unital C*-algebras to the category of real/complex unital operator systems. It is based on the characterization of…

Operator Algebras · Mathematics 2026-04-24 Samuel Tiersma