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Related papers: Quantum graphs where back-scattering is prohibited

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The paper is concerned with the number of open gaps in spectra of periodic quantum graphs. The well-known conjecture by Bethe and Sommerfeld (1933) says that the number of open spectral gaps for a system periodic in more than one direction…

Mathematical Physics · Physics 2017-11-16 Pavel Exner , Ondřej Turek

The quantum scattering by smooth bodies is considered for small and large values of $kd$, with $k$ the wavenumber and $d$ the scale of the body. In both regimes, we prove that the forward scattering exceeds the backscattering. For high $k$,…

Mathematical Physics · Physics 2007-05-23 W. De Roeck , E. L. Lakshtanov

Quantum walks on graphs have shown prioritized benefits and applications in wide areas. In some scenarios, however, it may be more natural and accurate to mandate high-order relationships for hypergraphs, due to the density of information…

Quantum Physics · Physics 2017-09-26 Ying Liu , Jiabin Yuan , Bojia Duan , Dan Li

We outline some recent proofs of quantum ergodicity on large graphs and give new applications in the context of irregular graphs. We also discuss some remaining questions.

Spectral Theory · Mathematics 2019-02-01 Nalini Anantharaman , Mostafa Sabri

In this expository article we present an overview of the current state-of-the-art in post-quantum group-based cryptography. We describe several families of groups that have been proposed as platforms, with special emphasis in polycyclic…

Cryptography and Security · Computer Science 2023-01-18 Delaram Kahrobaei , Ramón Flores , Marialaura Noce

The construction of large-scale quantum computers will require modular architectures that allow physical resources to be localized in easy-to-manage packages. In this work, we examine the impact of different graph structures on the…

We give a new formula for computing the isospectral reduction of a matrix (and graph) down to a submatrix (or subgraph). Using this, we generalize the notion of isospectral reductions. In addition, we give a procedure for constructing a…

Combinatorics · Mathematics 2022-12-02 Mark Kempton , John Tolbert

We study the transmission of a quantum particle along a straight input--output line to which a graph $\Gamma$ is attached at a point. In the point of contact we impose a singularity represented by a certain properly chosen scale-invariant…

Quantum Physics · Physics 2013-03-22 Ondřej Turek , Taksu Cheon

Quantum families of maps between quantum spaces are defined and studied. We prove that quantum semigroup (and sometimes quantum group) structures arise naturally on such objects out of more fundamental properties. As particular cases we…

Operator Algebras · Mathematics 2015-06-26 Piotr M. Soltan

This paper introduces an efficient quantum computing method for reducing special graphs in the context of the graph coloring problem. The special graphs considered include both symmetric and non-symmetric graphs where the axis passes…

Quantum Physics · Physics 2025-10-21 Lord Sen , Shyamapada Mukherjee

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

An algorithm for quantum computing Hamiltonian cycles of simple, cubic, bipartite graphs is discussed. It is shown that it is possible to evolve a quantum computer into an entanglement of states which map onto the set of all possible paths…

Quantum Physics · Physics 2007-05-23 T. Rudolph

The study of quantum chromatic numbers of graphs is a hot research topic in recent years. However, the infinite family of graphs with known quantum chromatic numbers are rare, as far as we know, the only known such graphs (except for…

Combinatorics · Mathematics 2024-12-31 Xiwang Cao , Keqin Feng , Ying-Ying Tan

We present a new model of quantum gravity as a theory of random geometries given explicitly in terms of a multitrace matrix model. This is a generalization of the usual discretized random surfaces of 2D quantum gravity which works away from…

High Energy Physics - Theory · Physics 2017-11-22 Badis Ydri , Cherine Soudani , Ahlam Rouag

We determine explicit quantum seeds for classes of quantized matrix algebras. Furthermore, we obtain results on centers and block diagonal forms {of these algebras.} In the case where $q$ is {an arbitrary} root of unity, this further…

Quantum Algebra · Mathematics 2012-10-29 Hans Plesner Jakobsen , Chiara Pagani

First, I introduce quantum graph theory. I also discuss a known lower bound on the independence numbers and derive from it an upper bound on the chromatic numbers of quantum graphs. Then, I construct a family of quantum graphs that can be…

Quantum Physics · Physics 2014-12-01 Steven Lu

We construct a class of positive linear maps on matrix algebras. We find conditions when these maps are atomic, decomposable and completely positive. We obtain a large class of atomic positive linear maps. As applications in quantum…

Operator Algebras · Mathematics 2017-04-25 Xin Li , Wei Wu

We discuss Laplacian spectrum on a finite metric graph with vertex couplings violating the time-reversal invariance. For the class of star graphs we determine, under the condition of a fixed total edge length, the configurations for which…

Mathematical Physics · Physics 2025-03-14 Pavel Exner , Jonathan Rohleder

Quantum walks are roughly analogous to classical random walks, and like classical walks they have been used to find new (quantum) algorithms. When studying the behavior of large graphs or combinations of graphs it is useful to find the…

Quantum Physics · Physics 2015-10-28 Seth S. Cottrell

We introduce a new model of background independent physics in which the degrees of freedom live on a complete graph and the physics is invariant under the permutations of all the points. We argue that the model has a low energy phase in…

High Energy Physics - Theory · Physics 2007-05-23 Tomasz Konopka , Fotini Markopoulou , Lee Smolin
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