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We investigate under which conditions a mixed state on a finite-dimensional multipartite quantum system may be the unique, globally stable fixed point of frustration-free semigroup dynamics subject to specified quasi-locality constraints.…

Quantum Physics · Physics 2016-03-28 Peter D. Johnson , Francesco Ticozzi , Lorenza Viola

This paper studies a finite reversible lumpable Markov chain for which relaxed spectral compression yields a larger determinant than partition-constrained compression. For a symmetric six-state lumpable chain and the positive operator…

Probability · Mathematics 2026-04-14 Oleg Kiriukhin

The complete knowledge of the global and marginal second-order moments of a quantum state is in general insufficient for entanglement detection. By deriving the conditions on local-unitary (LU) transformations through the second-order…

Quantum Physics · Physics 2025-06-17 A. García-Velo , M. Paraschiv , Y. Ban , E. Torrontegui , R. Puebla

We prove that every GNS-symmetric quantum Markov semigroup on a finite dimensional matrix algebra satisfies a modified log-Sobolev inequality. In the discrete time setting, we prove that every finite dimensional GNS-symmetric quantum…

Quantum Physics · Physics 2022-06-01 Li Gao , Cambyse Rouzé

The reflected entropy $S_R(A:B)$ of a density matrix $\rho_{AB}$ is a bipartite correlation measure lower-bounded by the quantum mutual information $I(A:B)$. In holographic states satisfying the quantum extremal surface formula, where the…

High Energy Physics - Theory · Physics 2021-10-12 Patrick Hayden , Onkar Parrikar , Jonathan Sorce

For a locally compact quantum group $\mathbb{G}$, the quantum group algebra $L^1(\mathbb{G})$ is operator amenable if and only if it has an operator bounded approximate diagonal. It is known that if $L^1(\mathbb{G})$ is operator biflat and…

Operator Algebras · Mathematics 2014-12-02 Benjamin Willson

The paper deals with homogenization problem for a non-local linear operator with a kernel of convolution type in a medium with a periodic structure. We consider the natural diffusive scaling of this operator and study the limit behaviour of…

Functional Analysis · Mathematics 2016-04-19 Andrey Piatnitski , Elena Zhizhina

This paper studies projections of uniform random elements of (co)adjoint orbits of compact Lie groups. Such projections generalize several widely studied ensembles in random matrix theory, including the randomized Horn's problem, the…

Mathematical Physics · Physics 2023-10-25 Benoît Collins , Colin McSwiggen

In this paper, we consider the problem of minimizing quantum free energies under the constraint that the density of particles is fixed at each point of Rd, for any d $\ge$ 1. We are more particularly interested in the characterization of…

Mathematical Physics · Physics 2019-04-02 Romain Duboscq , Olivier Pinaud

In this paper we consider the conditions under which a given ensemble of two-qubit states can be optimally distinguished by local operations and classical communication (LOCC). We begin by completing the \emph{perfect} distinguishability…

Quantum Physics · Physics 2014-05-14 Eric Chitambar , Runyao Duan , Min-Hsiu Hsieh

Hoang, Levit, Mandrescu and Pham asked for structural conditions ensuring that the independence polynomial of a $\W_p$ graph is log-concave, or at least unimodal, and conjectured that a connected $\W_2$ graph is $2$-quasi-regularizable if…

Combinatorics · Mathematics 2026-05-15 Kevin Pereyra

The richness of quantum theory's reversible dynamics is one of its unique operational characteristics, with recent results suggesting deep links between the theory's reversible dynamics, its local state space and the degree of non-locality…

Quantum Physics · Physics 2016-01-20 Sabri W. Al-Safi , Jonathan Richens

The effect of a BULK marginal operator on BOUNDARY critical phenomena in two space-time dimensions is considered. The particular case of an open S=1/2 antiferromagnetic Heisenberg chain, corresponding to a Wess-Zumino-Witten non-linear…

Strongly Correlated Electrons · Physics 2016-08-31 Ian Affleck , Shaojin Qin

Nonlocality exhibited by ensembles of composite quantum states, wherein local operations and classical communication (LOCC) yield suboptimal discrimination probabilities compared to global strategies, is one of the striking nonclassical…

Quantum Physics · Physics 2025-12-02 Samrat Sen

We study polynomial optimization problems whose objective has a composition or tensor train structure. These polynomials can be evaluated as a sequence of maps, giving rise to intermediate variables (``states'') of dimension lower than the…

Optimization and Control · Mathematics 2026-04-21 Llorenç Balada Gaggioli , Didier Henrion , Milan Korda

We study the entanglement structure, i.e., the structure of quantum composite system from operational aspects. The structure is not uniquely determined in General Probabilistic Theories (GPTs) even if we impose reasonable postulate about…

Quantum Physics · Physics 2022-05-30 Hayato Arai , Masahito Hayashi

We provide a necessary condition that a quantum measurement can be implemented by the class of protocols known as Local Operations and Classical Communication, or LOCC, including when an error is allowed but must vanish in the limit of an…

Quantum Physics · Physics 2022-02-17 Scott M. Cohen

Organising the space of entanglement structures of a multipartite quantum system is a much more challenging task than its bipartite version: while the local unitary (LU) orbit of a bipartite pure state can be conveniently characterized by…

Mathematical Physics · Physics 2026-04-03 Sylvain Carrozza , Johann Chevrier , Luca Lionni

In classical information theory one can, in principle, produce a perfect copy of any input state. In quantum information theory, the no cloning theorem prohibits exact copying of nonorthogonal states. Moreover, if we wish to copy…

Quantum Physics · Physics 2009-11-10 Fabio Anselmi , Anthony Chefles , Martin B. Plenio

We discuss existence of mixed state of multicomponent system with given spectrum and given reduced density matrices. We give a complete solution of the problem in terms of linear inequalities on the spectra, accompanied with extensive…

Quantum Physics · Physics 2007-05-23 Alexander Klyachko