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Related papers: Convexity of quantum $\chi^2$-divergence

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The data processing inequality is central to information theory and motivates the study of monotonic divergences. However, it is not clear operationally we need to consider all such divergences. We establish a simple method for Pinsker…

Information Theory · Computer Science 2025-04-02 Ian George , Alice Zheng , Akshay Bansal

Most quantum divergences derive their structure from classical f-divergences or Renyi-type constructions, a dependence that obscures several quantum geometric effects. We introduce a quantum relative-alpha-entropy that extends Umegaki's…

Quantum Physics · Physics 2026-04-09 Sayantan Roy , Atin Gayen , Aditi Kar Gangopadhyay , Sugata Gangopadhyay

We investigate the global chirality distribution of the quantum walk on the line when decoherence is introduced either through simultaneous measurements of the chirality and particle position, or as a result of broken links. The first…

Quantum Physics · Physics 2015-05-19 Alejandro Romanelli , Guzmán Hernández

This work explores properties of Strong Data-Processing constants for R\'enyi Divergences. Parallels are made with the well-studied $\varphi$-Divergences, and it is shown that the order $\alpha$ of R\'enyi Divergences dictates whether…

Information Theory · Computer Science 2026-01-15 Adrien Vandenbroucque , Amedeo Roberto Esposito , Michael Gastpar

In the field of statistics, many kind of divergence functions have been studied as an amount which measures the discrepancy between two probability distributions. In the differential geometrical approach in statistics (information…

Methodology · Statistics 2018-09-11 Tomohiro Nishiyama

In this paper, we first introduce and define several new information divergences in the space of transition matrices of finite Markov chains which measure the discrepancy between two Markov chains. These divergences offer natural…

Information Theory · Computer Science 2023-12-11 Youjia Wang , Michael C. H. Choi

We develop an approximation approach to infinite dimensional quantum channels based on detailed investigation of the continuity properties of entropic characteristics of quantum channels and operations (trace-nonincreasing completely…

Quantum Physics · Physics 2008-12-17 M. E. Shirokov , A. S. Holevo

In this paper we consider the $\chi$-function (the Holevo capacity of constrained channel) and the convex closure of the output entropy for arbitrary infinite dimensional channel. It is shown that the $\chi$-function of an arbitrary channel…

Quantum Physics · Physics 2009-11-10 M. E. Shirokov

In this paper, we obtain some new inequalities for ({\alpha},m)-convex functions. The analysis used in the proofs is fairly elementary and based on the use of Power-mean inequality.

Functional Analysis · Mathematics 2012-09-25 M. Emin Ozdemir , Merve Avci Ardic

We study differentiable strongly quasiconvex functions for providing new properties for algorithmic and monotonicity purposes. Furthemore, we provide insights into the decreasing behaviour of strongly quasiconvex functions, applying this…

Optimization and Control · Mathematics 2024-10-07 Felipe Lara , Raúl T. Marcavillaca , Phan T. Vuong

The position density of a "particle" performing a continuous-time quantum walk on the integer lattice, viewed on length scales inversely proportional to the time t, converges (as t tends to infinity) to a probability distribution that…

Quantum Physics · Physics 2013-05-29 Alex D. Gottlieb

The generalized Marcum functions $Q_{\mu}(x,y)$ and $P_{\mu}(x,y)$ have as particular cases the non-central $\chi^2$ and gamma cumulative distributions, which become central distributions (incomplete gamma function ratios) when the…

Classical Analysis and ODEs · Mathematics 2014-06-25 J. Segura

This paper proposes and studies new quantum version of $f$-divergences, a class of convex functionals of a pair of probability distributions including Kullback-Leibler divergence, Rnyi-type relative entropy and so on. There are several…

Quantum Physics · Physics 2018-02-07 Keiji Matsumoto

Large deviation principles are established for the two-parameter Poisson-Dirichlet distribution and two-parameter Dirichlet process when parameter $\theta$ approaches infinity. The motivation for these results is to understand the…

Probability · Mathematics 2007-05-23 Shui Feng

The maximal correlation coefficient measures the linear correlation in a bipartite distribution and contraction coefficients measure how much information is lost under a noisy channel. Remarkably, Raginsky established a close relation…

Quantum Physics · Physics 2026-03-31 Ian George , Marco Tomamichel

Divergences are quantities that measure discrepancy between two probability distributions and play an important role in various fields such as statistics and machine learning. Divergences are non-negative and are equal to zero if and only…

Statistics Theory · Mathematics 2019-10-22 Tomohiro Nishiyama

Fawzi and Fawzi recently defined the sharp R\'enyi divergence, $D_\alpha^\#$, for $\alpha \in (1, \infty)$, as an additional quantum R\'enyi divergence with nice mathematical properties and applications in quantum channel discrimination and…

Quantum Physics · Physics 2021-10-12 Bjarne Bergh , Robert Salzmann , Nilanjana Datta

A new canonical divergence is put forward for generalizing an information-geometric measure of complexity for both, classical and quantum systems. On the simplex of probability measures it is proved that the new divergence coincides with…

Mathematical Physics · Physics 2019-06-11 Domenico Felice , Stefano Mancini , Nihat Ay

A theory of canonical basis for a two-parameter quantum algebra is developed in parallel with the one in one-parameter case. A geometric construction of the negative part of a two-parameter quantum algebra is given by using mixed perverse…

Representation Theory · Mathematics 2013-11-06 Zhaobing Fan , Yiqiang Li

We present a quantum algorithm to compute the discrete Legendre-Fenchel transform. Given access to a convex function evaluated at $N$ points, the algorithm outputs a quantum-mechanical representation of its corresponding discrete…

Quantum Physics · Physics 2021-03-18 David Sutter , Giacomo Nannicini , Tobias Sutter , Stefan Woerner