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We study four dimensional N=1 gauge theories that arise on the worldvolume of D3-branes probing complex cones over del Pezzo surfaces. Global symmetries of the gauge theories are made explicit by using a correspondence between bifundamental…

High Energy Physics - Theory · Physics 2009-11-10 Sebastian Franco , Amihay Hanany , Pavlos Kazakopoulos

The zero-divisor graph of a finite commutative ring with unity is the graph whose vertex set is the set of zero-divisors in the ring, with $a$ and $b$ adjacent if $ab=0$. We show that the class of zero-divisor graphs is universal, in the…

Rings and Algebras · Mathematics 2022-07-26 G. Arunkumar , Peter J. Cameron , T. Kavaskar , T. Tamizh Chelvam

Some two qubit interactions are singly sufficient for universal quantum computation but not without the use of an ancilla. Recent schemes for universal quantum computation have focused on hybrid physical systems using ancillae. In them, the…

Quantum Physics · Physics 2014-02-03 Kerem Halil-Shah , Daniel K. L. Oi

Entanglement is a fundamental resource for many applications in quantum information processing. Here, we investigate how quantum transport in simple quantum graphs, modeled as controlled two-level quantum systems, can be utilized to…

Quantum Physics · Physics 2025-10-24 Alison A. Silva , D. Bazeia , Fabiano M. Andrade

Two geometric interpretations of the bar automorphism in the positive part of a quantized enveloping algebra are given. The first is in terms of numbers of rational points over finite fields of quiver analogues of orbital varieties; the…

Representation Theory · Mathematics 2007-05-23 Philippe Caldero , Markus Reineke

A self-contained graph is an infinite graph which is isomorphic to one of its proper induced subgraphs. In this paper, these graphs are studied by presenting some examples and defining some of their sub-structures such as removable…

Combinatorics · Mathematics 2016-11-04 Mohammad Hadi Shekarriz , Madjid Mirzavaziri

We establish a quantum version of Frucht's Theorem, proving that every finite quantum group is the quantum automorphism group of an undirected finite quantum graph. The construction is based on first considering several quantum Cayley…

Operator Algebras · Mathematics 2025-10-20 Michael Brannan , Daniel Gromada , Junichiro Matsuda , Adam Skalski , Mateusz Wasilewski

Quantum walks provide a natural framework to approach graph problems with quantum computers, exhibiting speedups over their classical counterparts for tasks such as the search for marked nodes or the prediction of missing links.…

Quantum Physics · Physics 2023-06-27 Duarte Magano , João Moutinho , Bruno Coutinho

We investigate which entanglement resources allow universal measurement-based quantum computation via single-qubit operations. We find that any entanglement feature exhibited by the 2D cluster state must also be present in any other…

Quantum Physics · Physics 2007-05-23 Maarten Van den Nest , Akimasa Miyake , Wolfgang Dür , Hans J. Briegel

Classical random walks on finite graphs have an underrated property: a walk from any vertex can reach every other vertex in finite time, provided they are connected. Discrete-time quantum walks on finite connected graphs however, can have…

Quantum Physics · Physics 2023-01-18 Prithviraj Prabhu , Todd A. Brun

Simulating physical systems on near-term quantum computers often requires preparing states within constrained subspaces, like those with fixed particle number or spin. We use Lie algebraic techniques to prove that hardware-efficient gates…

Quantum Physics · Physics 2026-05-05 Andreas Stergiou , Nicolas PD Sawaya

A finite graph $\Gamma$ is called $G$-symmetric if $G$ is a group of automorphisms of $\Gamma$ which is transitive on the set of ordered pairs of adjacent vertices of $\Gamma$. We study a family of symmetric graphs, called the unitary…

Combinatorics · Mathematics 2015-03-25 Massimo Giulietti , Stefano Marcugini , Fernanda Pambianco , Sanming Zhou

It is an oft-cited fact that no quantum code can support a set of fault-tolerant logical gates that is both universal and transversal. This no-go theorem is generally responsible for the interest in alternative universality constructions…

Quantum Physics · Physics 2016-09-20 Theodore J. Yoder , Ryuji Takagi , Isaac L. Chuang

Let $X$ be a family of graphs and $X_n$ the set of $n$-vertex graphs in $X$. A graph $U^{(n)}$ containing all graphs from $X_n$ as induced subgraphs is called $n$-universal for $X$. Moreover, we say that $U^{(n)}$ is a proper $n$-universal…

Combinatorics · Mathematics 2013-07-24 Aistis Atminas , Sergey Kitaev , Vadim V. Lozin , Alexandr Valyuzhenich

Let $S$ be a set of transpositions such that the girth of the transposition graph of $S$ is at least 5. It is shown that the automorphism group of the Cayley graph of the permutation group $H$ generated by $S$ is the semidirect product…

Discrete Mathematics · Computer Science 2013-06-18 Ashwin Ganesan

Stanislaw Ulam asked whether there exists a universal countable planar graph (that is, a countable planar graph that contains every countable planar graph as a subgraph). J\'anos Pach (1981) answered this question in the negative. We…

Combinatorics · Mathematics 2021-09-02 Tony Huynh , Bojan Mohar , Robert Šámal , Carsten Thomassen , David R. Wood

Anomalous chiral conductivities in theories with global anomalies are independent of whether they are computed in a weakly coupled quantum (or thermal) field theory, hydrodynamics, or at infinite coupling from holography. While the presence…

High Energy Physics - Theory · Physics 2016-10-18 Sašo Grozdanov , Napat Poovuttikul

Gauging is a general procedure for mapping a quantum many-body system with a global symmetry to one with a local gauge symmetry. We consider a generalized gauging map that does not enforce gauge symmetry at all lattice sites, and show that…

Quantum Physics · Physics 2024-03-15 Kfir Dolev , Vladimir Calvera , Sam Cree , Dominic J. Williamson

Commutativity gadgets provide a technique for lifting classical reductions between constraint satisfaction problems to quantum-sound reductions between the corresponding nonlocal games. We develop a general framework for commutativity…

Quantum Physics · Physics 2026-04-03 Eric Culf , Josse van Dobben de Bruyn , Peter Zeman

Suppose we can apply a given 2-qubit Hamiltonian H to any (ordered) pair of qubits. We say H is n-universal if it can be used to approximate any unitary operation on n qubits. While it is well known that almost any 2-qubit Hamiltonian is…

Quantum Physics · Physics 2018-12-20 Andrew M. Childs , Debbie Leung , Laura Mančinska , Maris Ozols