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Related papers: Categorical (Co)Limits of Quantum Graphs

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We show that any two Hadamard graphs on the same number of vertices are quantum isomorphic. This follows from a more general recipe for showing quantum isomorphism of graphs arising from certain association schemes. The main result is built…

Combinatorics · Mathematics 2022-10-27 Ada Chan , William J. Martin

We develop two approaches to Quantum (or Non-commutative) Graphs based on arbitrary von Neumann algebras $M\subseteq\mathcal B(H)$: one looking at operator bimodules of Hilbert--Schmidt (instead of bounded) operators, and the second looking…

Operator Algebras · Mathematics 2025-12-01 Matthew Daws

We investigate quantum and nonsignaling generalizations of perfect matchings in graphs using nonlocal games. Specifically, we introduce nonlocal games that test for $L$-perfect matchings in bipartite graphs, perfect matchings in general…

Quantum Physics · Physics 2025-02-10 David Cui , Laura Mančinska , Seyed Sajjad Nezhadi , David E. Roberson

Any directed graph G with N vertices and J edges has an associated line-graph L(G) where the J edges form the vertices of L(G). We show that the non-zero eigenvalues of the adjacency matrices are the same for all graphs of such a family…

Chaotic Dynamics · Physics 2007-05-23 Prot Pakonski , Gregor Tanner , Karol Zyczkowski

Categorical quantum mechanics (CQM) and the theory of quantum groups rely heavily on the use of structures that have both an algebraic and co-algebraic component, making them well-suited for manipulation using diagrammatic techniques.…

Logic in Computer Science · Computer Science 2014-12-31 Aleks Kissinger , David Quick

We consider a twisted version of quantum groups corepresentations. This generalization amounts to include in the theory the case where quantum space coordinates and its endomorphism matrix entries belong to a non-commutative quadratic…

Quantum Algebra · Mathematics 2007-05-23 H. Montani , R. Trinchero

We investigate the bottom of the spectra of infinite quantum graphs, i.e., Laplace operators on metric graphs having infinitely many edges and vertices. We introduce a new definition of the isoperimetric constant for quantum graphs and then…

Spectral Theory · Mathematics 2018-12-17 Aleksey Kostenko , Noema Nicolussi

We present a strong connection between quantum information and quantum permutation groups. Specifically, we define a notion of quantum isomorphisms of graphs based on quantum automorphisms from the theory of quantum groups, and then show…

Quantum Physics · Physics 2018-04-02 Martino Lupini , Laura Mančinska , David E. Roberson

The "noncommutative graphs" which arise in quantum error correction are a special case of the quantum relations introduced in [N. Weaver, Quantum relations, Mem. Amer. Math. Soc. 215 (2012), v-vi, 81-140]. We use this perspective to…

Operator Algebras · Mathematics 2017-06-30 Nik Weaver

Motivated by the theory of Cuntz-Krieger algebras we define and study $ C^\ast $-algebras associated to directed quantum graphs. For classical graphs the $ C^\ast $-algebras obtained this way can be viewed as free analogues of Cuntz-Krieger…

Operator Algebras · Mathematics 2020-09-22 Mike Brannan , Kari Eifler , Christian Voigt , Moritz Weber

Quantum graphs have recently emerged as models of nonlinear optical, quantum confined systems with exquisite topological sensitivity and the potential for predicting structures with an intrinsic, off-resonance response approaching the…

Optics · Physics 2013-05-21 Rick Lytel , Shoresh Shafei , Mark G. Kuzyk

Quantum graphs are a paradigmatic model for quantum chaos as well as for spectral theory. We give a concise didactical introduction to quantum graphs, or Schr\"odinger Hamiltonians on metric graphs, with a focus on results related to…

Quantum Physics · Physics 2026-05-07 Gregory Berkolaiko , Sven Gnutzmann

We introduce some equivalent notions of homomorphisms between quantum groups that behave well with respect to duality of quantum groups. Our equivalent definitions are based on bicharacters, coactions, and universal quantum groups,…

Operator Algebras · Mathematics 2015-10-23 Ralf Meyer , Sutanu Roy , Stanisław Lech Woronowicz

We consider two Z/2Z-actions on the Podles generic quantum spheres. They yield, as noncommutative quotient spaces, the Klimek-Lesniewski q-disc and the quantum real projective space, respectively. The C*-algebras of all these quantum spaces…

Quantum Algebra · Mathematics 2009-11-07 P. M. Hajac , R. Matthes , W. Szymanski

Based on earlier work on regular quantum graphs we show that a large class of scaling quantum graphs with arbitrary topology are explicitly analytically solvable. This is surprising since quantum graphs are excellent models of quantum chaos…

Quantum Physics · Physics 2009-11-10 Yu. Dabaghian , R. Blümel

The notion of the quantum automorphism group of a graph was introduced by J. Bichon in 2003 and T. Banica in 2005 respectively. This article explores primarily the quantum automorphism group of a graph $\Gamma$, denoted by…

Operator Algebras · Mathematics 2025-11-20 Rajibul Haque , Ujjal Karmakar , Arnab Mandal

We consider circulant graphs having $p$ vertices, with $p$ prime. To any such graph we associate a certain number $k$, that we call type of the graph. We prove that for $p>>k$ the graph has no quantum symmetry, in the sense that the quantum…

Combinatorics · Mathematics 2007-08-30 Teodor Banica , Julien Bichon , Gaetan Chenevier

In the flavour of categorical quantum mechanics, we extend nonlocal games to allow quantum questions and answers, using quantum sets (special symmetric dagger Frobenius algebras) and the quantum functions of Musto, Reutter, and Verdon…

Quantum Physics · Physics 2026-01-14 Adina Goldberg

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

A factor-graph representation of quantum-mechanical probabilities (involving any number of measurements) is proposed. Unlike standard statistical models, the proposed representation uses auxiliary variables (state variables) that are not…

Information Theory · Computer Science 2017-06-13 Hans-Andrea Loeliger , Pascal O. Vontobel