English
Related papers

Related papers: Equilibrium and ground states from Cayley graphs

200 papers

To a large class of graphs of groups we associate a C*-algebra universal for generators and relations. We show that this C*-algebra is stably isomorphic to the crossed product induced from the action of the fundamental group of the graph of…

Operator Algebras · Mathematics 2021-07-27 Nathan Brownlowe , Alexander Mundey , David Pask , Jack Spielberg , Anne Thomas

We present simple graph-theoretic characterizations of Cayley graphs for left-cancellative monoids, groups, left-quasigroups and quasigroups. We show that these characterizations are effective for the end-regular graphs of finite degree.

Discrete Mathematics · Computer Science 2018-03-26 Didier Caucal

We consider fiberwise singly generated Fell-bundles over etale groupoids. Given a continuous real-valued 1-cocycle on the groupoid, there is a natural dynamics on the cross-sectional algebra of the Fell bundle. We study the…

Operator Algebras · Mathematics 2021-07-01 Zahra Afsar , Aidan Sims

We investigate compact quantum group actions on unital $C^*$-algebras by analyzing invariant subsets and invariant states. In particular, we come up with the concept of compact quantum group orbits and use it to show that countable compact…

Operator Algebras · Mathematics 2015-11-17 Huichi Huang

Mass-action kinetics and its generalizations appear in mathematical models of (bio-)chemical reaction networks, population dynamics, and epidemiology. The dynamical systems arising from directed graphs are generally non-linear and difficult…

Dynamical Systems · Mathematics 2019-08-28 Gheorghe Craciun , Stefan Muller , Casian Pantea , Polly Y. Yu

We have defined and established a theory of cofinite connectedness of a cofinite graph. Many of the properties of connectedness of topological spaces have analogs for cofinite connectedness. We have seen that if $G$ is a cofinite group and…

General Topology · Mathematics 2016-02-05 Amrita Acharyya , Jon M. Corson , Bikash Das

We study KMS states on finite-graph C*-algebras with sinks and sources. We compare finite-graph C*-algebras with C*-algebras associated with complex dynamical systems of rational functions. We show that if the inverse temperature $\beta$ is…

Operator Algebras · Mathematics 2010-07-27 Tsuyoshi Kajiwara , Yasuo Watatani

We derive the universal real time $U(1)$ topological gauge field action for mixed quantum states of weakly correlated fermions in all dimensions, and demonstrate its independence of the underlying equilibrium or non-equilibrium nature of…

Statistical Mechanics · Physics 2022-12-28 Ze-Min Huang , Xiao-Qi Sun , Sebastian Diehl

In this article we apply the methods outlined in the previous paper of this series to the particular set of states obtained by choosing the complexifier to be a Laplace operator for each edge of a graph. The corresponding coherent state…

High Energy Physics - Theory · Physics 2009-10-31 T. Thiemann , O. Winkler

We study the internal structure of $C^*$-algebras of right LCM monoids by means of isolating the core semigroup $C^*$-algebra as the coefficient algebra of a Fock-type module on which the full semigroup $C^*$-algebra admits a left action.…

Operator Algebras · Mathematics 2019-02-08 Nathan Brownlowe , Nadia S. Larsen , Jacqui Ramagge , Nicolai Stammeier

We construct a generalized class of quantum gravity condensate states, that allows the description of continuum homogeneous quantum geometries within the full theory. They are based on similar ideas already applied to extract effective…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Daniele Oriti , Daniele Pranzetti , James P. Ryan , Lorenzo Sindoni

We study Cayley graphs of abelian groups from the perspective of quantum symmetries. We develop a general strategy for determining the quantum automorphism groups of such graphs. Applying this procedure, we find the quantum symmetries of…

Quantum Algebra · Mathematics 2024-02-07 Daniel Gromada

We present simple graph-theoretic characterizations of Cayley graphs for monoids, semigroups and groups. We extend these characterizations to commutative monoids, semilattices, and abelian groups.

Discrete Mathematics · Computer Science 2019-03-18 Didier Caucal

Gauge theories with finite gauge groups have applications to quantum simulation and quantum gravity. Recently, the exact number of gauge-invariant states was computed for pure gauge theories on arbitrary lattices. In this work, we…

Quantum Physics · Physics 2025-11-20 Alessandro Mariani

We calculate the S-invariant of Connes for the von Neumann algebra factors arising from KMS-weights of a generalized gauge action on a simple graph C*-algebra when the associated measure on the infinite path space of the graph is…

Operator Algebras · Mathematics 2020-02-14 Klaus Thomsen

We determine the structure of equilibrium states for a natural dynamics on the boundary quotient diagram of $C^*$-algebras for a large class of right LCM semigroups. The approach is based on abstract properties of the semigroup and covers…

Operator Algebras · Mathematics 2019-02-08 Zahra Afsar , Nathan Brownlowe , Nadia S. Larsen , Nicolai Stammeier

We introduce the notion of the action of a group on a labeled graph and the quotient object, also a labeled graph. We define a skew product labeled graph and use it to prove a version of the Gross-Tucker theorem for labeled graphs. We then…

Operator Algebras · Mathematics 2013-05-17 Teresa Bates , David Pask , Paulette Willis

We have generalised the concept of graph states to what we have called mixed graph states, which we define in terms of mixed graphs, that is graphs with both directed and undirected edges, as the density matrix stabilized by the associated…

Quantum Physics · Physics 2016-03-17 Constanza Riera , Ramij Rahaman , Matthew G. Parker

KMS states on $\mathbb{Z}_2$-crossed products of unital $C^*$-algebras $\mathcal{A}$ are characterized in terms of KMS states and twisted KMS functionals of $\mathcal{A}$. These functionals are shown to describe the extensions of KMS states…

Operator Algebras · Mathematics 2024-03-15 Ricardo Correa da Silva , Johannes Grosse , Gandalf Lechner

In this paper, firstly, we provide some necessary and sufficient conditions for generalized Cayley graphs on abelian groups to be bipartite. Secondly, we deduce several necessary and sufficient conditions for generalized Cayley graphs on…

Combinatorics · Mathematics 2024-12-18 Liao Qianfen , Liu Weijun , Zhang Pengli