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Although quantum coherence is a basic trait of quantum mechanics, the presence of coherences in the quantum description of a certain phenomenon does not rule out the possibility to give an alternative description of the same phenomenon in…

Quantum Physics · Physics 2018-12-07 Andrea Smirne , Dario Egloff , María García Díaz , Martin B. Plenio , Susana F. Huelga

The problem of discriminating between many quantum channels with certainty is analyzed under the assumption of prior knowledge of algebraic relations among possible channels. It is shown, by explicit construction of a novel family of…

Quantum Physics · Physics 2021-08-04 Zane M. Rossi , Isaac L. Chuang

We introduce and investigate a new generalized convexity notion for functions called prox-convexity. The proximity operator of such a function is single-valued and firmly nonexpansive. We provide examples of (strongly) quasiconvex, weakly…

Optimization and Control · Mathematics 2021-11-30 Sorin-Mihai Grad , Felipe Lara

Generalized quantum measurements with N distinct outcomes are used for determining the density matrix, of order d, of an ensemble of quantum systems. The resulting probabilities are represented by a point in an N-dimensional space. It is…

Quantum Physics · Physics 2009-10-31 Asher Peres , Daniel Terno

Recently, a new definition for quantum $f$-divergences was introduced based on an integral representation. These divergences have shown remarkable properties, for example when investigating contraction coefficients under noisy channels. At…

Quantum Physics · Physics 2025-01-08 Salman Beigi , Christoph Hirche , Marco Tomamichel

We provide new results for computing and comparing the quantum gate fidelity of quantum channels via their Choi matrices. We extend recent work that showed there exist non-dual pairs of quantum channels with equal gate fidelity by providing…

Quantum Physics · Physics 2012-03-06 Nathaniel Johnston , David W. Kribs

Given a finitely-connected bounded planar domain $\Omega$, it is possible to define a {\it divergence distance} $D(x,y)$ from $x\in\Omega$ to $y\in\Omega$, which takes into account the complex geometry of the domain. This distance function…

Complex Variables · Mathematics 2018-01-23 Renjie Chen , Craig Gotsman , Kai Hormann

An issue which has attracted increasing attention in contemporary researches are Kirkwood--Dirac quasiprobabilities. List of their use includes many questions of quantum physics. Applications of complex tight frames in quantum information…

Quantum Physics · Physics 2024-07-12 Alexey E. Rastegin

One possibility of defining a quantum R\'enyi $\alpha$-divergence of two quantum states is to optimize the classical R\'enyi $\alpha$-divergence of their post-measurement probability distributions over all possible measurements (measured…

Quantum Physics · Physics 2023-01-18 Milán Mosonyi , Fumio Hiai

We consider a difference-of-convex formulation where one of the terms is allowed to be hypoconvex (or weakly convex). We first examine the precise behavior of a single iteration of the Difference-of-Convex algorithm (DCA), giving a tight…

Optimization and Control · Mathematics 2024-03-26 Teodor Rotaru , Panagiotis Patrinos , François Glineur

We investigate the dynamics of a quantum particle in disordered tight-binding models in one and two dimensions which are exceptions to the common wisdom on Anderson localization, in the sense that the localization length diverges at some…

Disordered Systems and Neural Networks · Physics 2015-03-17 P. L. Krapivsky , J. M. Luck

We show finite-size bounds on the deviation of the optimal type II error from its asymptotic value in the quantum hypothesis testing problem of Stein's lemma with composite null-hypothesis. The proof is based on some simple properties of a…

Quantum Physics · Physics 2014-07-07 Milán Mosonyi

We investigate the behaviour of a particle moving on the quotient manifold $M=C^2/Z_$ which is derived from the EH metric as the two centers approach each other. In the classical region of the configuration space we specify the physically…

High Energy Physics - Theory · Physics 2007-05-23 A. Hatzinikitas

The set of doubly-stochastic quantum channels and its subset of mixtures of unitaries are investigated. We provide a detailed analysis of their structure together with computable criteria for the separation of the two sets. When applied to…

Quantum Physics · Physics 2014-07-30 Christian B. Mendl , Michael M. Wolf

Quantum algorithms can potentially solve a handful of problems more efficiently than their classical counterparts. In that context, it has been discussed that Markov chains problems could be solved significantly faster using quantum…

Quantum Physics · Physics 2025-12-01 Baptiste Claudon , Jean-Philip Piquemal , Pierre Monmarché

The "marginal" distributions for measurable coordinate and spin projection is introduced. Then, the analog of the Pauli equation for spin-1/2 particle is obtained for such probability distributions instead of the usual wave functions. That…

Quantum Physics · Physics 2009-11-06 S. Mancini , O. V. Man'ko , V. I. Man'ko , P. Tombesi

We analyze two ways to obtain distinguishability measures between quantum maps by employing the square root of the quantum Jensen-Shannon divergence, which forms a true distance in the space of density operators. The arising measures are…

Quantum Physics · Physics 2023-07-19 Diego G. Bussandri , Pedro W. Lamberti , Karol Życzkowski

We formulate the large deviations for a class of two scale chemical kinetic processes motivated from biological applications. The result is successfully applied to treat a genetic switching model with positive feedbacks. The corresponding…

Probability · Mathematics 2016-04-05 Tiejun Li , Feng Lin

For a class of stochastic differential equations with reflection for which a certain ${\mathbb{L}}^p$ continuity condition holds with $p>1$, it is shown that any weak solution that is a strong Markov process can be decomposed into the sum…

Probability · Mathematics 2010-10-12 Weining Kang , Kavita Ramanan

There is a long history of representing a quantum state using a quasi-probability distribution: a distribution allowing negative values. In this paper we extend such representations to deal with quantum channels. The result is a convex,…

Quantum Physics · Physics 2018-03-05 John van de Wetering
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