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Related papers: Operators Induced by Graphs

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In this paper, we consider the relation between Toeplitz operators and elements in von Neumann algebras generated by certain graph groupoids.

Representation Theory · Mathematics 2010-07-20 Ilwoo Cho , Palle E. T. Jorgensen

We expand on some invariants used for classifying nonselfadjoint operator algebras. Specifically to nonselfadjoint operator algebras which have a conditional expectation onto a commutative diagonal we construct an edge-colored directed…

Operator Algebras · Mathematics 2013-07-23 Benton Duncan

We undertake a comprehensive study of structural properties of graph products of von Neumann algebras equipped with faithful, normal states, as well as properties of the graph products relative to subalgebras coming from induced subgraphs.…

Operators are induced on fermion and zeon algebras by the action of adjacency matrices and combinatorial Laplacians on the vector spaces spanned by the graph's vertices. Properties of the algebras automatically give information about the…

Combinatorics · Mathematics 2021-03-31 G. Stacey Staples

We discuss ways in which momentum operators can be introduced on an oriented metric graph. A necessary condition appears to the balanced property, or a matching between the numbers of incoming and outgoing edges; we show that a graph…

Mathematical Physics · Physics 2020-02-07 Pavel Exner

We define nonselfadjoint operator algebras with generators $L_{e_1},..., L_{e_n}, L_{f_1},...,L_{f_m}$ subject to the unitary commutation relations of the form \[ L_{e_i}L_{f_j} = \sum_{k,l} u_{i,j,k,l} L_{f_l}L_{e_k}\] where $u=…

Operator Algebras · Mathematics 2007-05-23 Stephen C. Power , Baruch Solel

Let $E$ and $F$ be Hilbert $C^*$-modules over a $C^*$-algebra $\CAlg{A}$. New classes of (possibly unbounded) operators $t:E\to F$ are introduced and investigated. Instead of the density of the domain $\Def(t)$ we only assume that $t$ is…

Operator Algebras · Mathematics 2015-07-09 René Gebhardt , Konrad Schmüdgen

This paper studies infinite graphs produced from a natural unfolding operation applied to finite graphs. Graphs produced via such operations are of finite degree and automatic over the unary alphabet (that is, they can be described by…

Logic · Mathematics 2008-09-22 Bakhadyr Khoussainov , Jiamou Liu , Mia Minnes

We study generalizations of the "contraction-deletion" relation of the Tutte polynomial, and other similar simple operations, to other graph parameters. The question can be set in the framework of graph algebras introduced by Freedman,…

Combinatorics · Mathematics 2007-05-23 Laszlo Lovasz , Balazs Szegedy

We define and investigate properties of universal operator algebras of directed graphs. Results include free products decomposition and continuity of the construction with respect to direct limits. Lastly we prove some K-theoretic results…

Operator Algebras · Mathematics 2007-05-23 Benton L. Duncan

Two distinct projections of finite rank $m$ are adjacent if their difference is an operator of rank two or, equivalently, the intersection of their images is $(m-1)$-dimensional. We extend this adjacency relation on other conjugacy classes…

Combinatorics · Mathematics 2020-06-30 Mark Pankov , Krzysztof Petelczyc , Mariusz Zynel

There has been a great deal of attention recently to graphs whose vertex set is a group, defined using the group structure. (The commuting graph, where two elements are joined if they commute, is the oldest and most famous example.) The…

Combinatorics · Mathematics 2026-02-03 Peter J. Cameron

Many interesting examples of operator algebras, both self-adjoint and non-self-adjoint, can be constructed from directed graphs. In this survey, we overview the construction of $C^*$-algebras from directed graphs and from two…

Operator Algebras · Mathematics 2022-09-07 Juliana Bukoski , Sushil Singla

We consider the graph whose vertex set is a conjugacy class ${\mathcal C}$ consisting of finite-rank self-adjoint operators on a complex Hilbert space $H$. The dimension of $H$ is assumed to be not less than $3$. In the case when operators…

Combinatorics · Mathematics 2021-11-05 Mark Pankov , Krzysztof Petelczyc , Mariusz Zynel

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

This paper mainly concerns the von Neumann algebras induced by a tuple of multiplication operators on Bergman spaces which arise essentially from holomorphic proper maps over higher dimensional domains. We study the structures and abelian…

Operator Algebras · Mathematics 2016-08-23 Pan Ma , Hansong Huang

Given a graph and a representation of its fundamental group, there is a naturally associated twisted adjacency operator. The main result of this article is the fact that these operators behave in a controlled way under graph covering maps.…

Combinatorics · Mathematics 2023-08-22 David Cimasoni , Adrien Kassel

Let $M$ be a finite von Neumann algebra. In the first part, we give asymptotic results about $M$-stable sequences of weak*-continuous mappings which are related with operators belonging to $M$. In the second part, we extend, by a shorter…

Operator Algebras · Mathematics 2007-05-23 Gilles Cassier

We introduced a family of infinite graphs directly associated with a class of von Neumann automaton model A_{G}. These are finite state models used in symbolic dynamics: stimuli models and in control theory. In the context of groupoid von…

Operator Algebras · Mathematics 2015-05-13 Ilwoo Cho , Palle E. T. Jorgensen

These notes concern aspects of various graphs whose vertex set is a group $G$ and whose edges reflect group structure in some way (so that they are invariant under the action of the automorphism group of $G$). The graphs I will discuss are…

Group Theory · Mathematics 2021-03-29 Peter J. Cameron
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