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Symmetry plays a crucial role in quantum physics, dictating the behavior and dynamics of physical systems. In this paper, we develop a hypothesis-testing framework for quantum dynamics symmetry using a limited number of queries to the…

Quantum Physics · Physics 2025-04-01 Yu-Ao Chen , Chenghong Zhu , Keming He , Yingjian Liu , Xin Wang

Quantitative analysis of discontinuity of basic characteristics of quantum states and channels is presented. First we consider general estimates for discontinuity jump (loss) of the von Neumann entropy for a given converging sequence of…

Quantum Physics · Physics 2021-09-28 M. E. Shirokov

Quantum networks will play a key role in distributed quantum information processing. As the network size increases, network-level errors like random breakdown and intentional attack are inevitable; therefore, it is important to understand…

Quantum Physics · Physics 2021-08-17 Bingzhi Zhang , Quntao Zhuang

In this work we prove that the possibility of superactivation of quantum channel capacities is determined by the mathematical properties of the quantum relative entropy function. Before our work this fundamental and purely mathematical…

Quantum Physics · Physics 2012-06-26 Laszlo Gyongyosi , Sandor Imre

Network tomography refers to the use of inference techniques for inferring internal network states from end-to-end probes. Quantum probes, implemented by sending blocks of $n$ coherent-state pulses augmented with continuous-variable (CV)…

Quantum Physics · Physics 2026-04-29 Yufei Zheng , Zihao Gong , Saikat Guha , Don Towsley

Quantum computing is poised to redefine the algorithmic foundations of communication systems. While quantum superposition and entanglement enable quadratic or exponential speedups for specific problems, identifying use cases where these…

Signal Processing · Electrical Eng. & Systems 2025-12-10 Naoki Ishikawa , Giuseppe Thadeu Freitas de Abreu , Petar Popovski , Robert W. Heath

There are different preparable quantum states in different network structures. The four nodes as a whole has two situations: one is the four nodes in a plane, the other is the four nodes in the space. In this paper, we obtain some…

Quantum Physics · Physics 2022-07-15 Yanwen Liang , Fengli Yan , Ting Gao

Quantum relative entropy, a quantum generalization of the renowned Kullback-Leibler divergence, serves as a fundamental measure of the distinguishability between quantum states and plays a pivotal role in quantum information science.…

Quantum Physics · Physics 2025-10-02 Yuchen Lu , Kun Fang

We propose a generalization of the quantum entropy power inequality involving conditional entropies. For the special case of Gaussian states, we give a proof based on perturbation theory for symplectic spectra. We discuss some implications…

Quantum Physics · Physics 2015-06-15 Robert Koenig

The precise one-shot characterisation of operational tasks in classical and quantum information theory relies on different forms of smooth entropic quantities. A particularly important connection is between the hypothesis testing relative…

Quantum Physics · Physics 2026-04-29 Bartosz Regula , Ludovico Lami , Nilanjana Datta

Quantum Inverse Problem (QIP) is the problem of estimating an unknown quantum system $\rho$ from a set of measurements, whereas the classical counterpart is the Inverse Problem of estimating a distribution from a set of observations. In…

Quantum Physics · Physics 2021-01-19 Ningping Cao , Jie Xie , Aonan Zhang , Shi-Yao Hou , Lijian Zhang , Bei Zeng

We investigate the hypercube networks that their nodes are considered as quantum harmonic oscillators. The entanglement of the ground state can be used to quantify the amount of information each part of a network shares with the rest of the…

Quantum Physics · Physics 2014-11-04 M. A. Jafarizadeh , F. Eghbalifam , S. Nami

It has been shown recently that the framework of quantum sampling, as introduced by Bouman and Fehr, can lead to new entropic uncertainty relations highly applicable to finite-key cryptographic analyses. Here we revisit these so-called…

Quantum Physics · Physics 2020-12-09 Keegan Yao , Walter O. Krawec , Jiadong Zhu

We give a simple proof of the uncertainty principle with quantum side information, as in [Berta et al. Nature Physics 6, 659 (2010)], invoking the monotonicity of the relative entropy. Our proof shows that the entropic uncertainty principle…

Quantum Physics · Physics 2011-12-08 Patrick J. Coles , Li Yu , Michael Zwolak

This article provides an elementary introduction to Gaussian channels and their capacities. We review results on the classical, quantum, and entanglement assisted capacities and discuss related entropic quantities as well as additivity…

Quantum Physics · Physics 2009-05-15 J. Eisert , M. M. Wolf

Quantum state estimation (or state tomography) is an indispensable task in quantum information processing. Because full state tomography that determines all elements of the density matrix is computationally demanding, one usually takes the…

Quantum Physics · Physics 2023-09-21 Hiroshi Yano , Naoki Yamamoto

Quantum systems may contain underlying correlations which are inaccessible to computationally bounded observers. We capture this distinction through a framework that analyses bipartite states only using efficiently implementable quantum…

Quantum Physics · Physics 2026-04-20 Álvaro Yángüez , Noam Avidan , Jan Kochanowski , Thomas A. Hahn

We consider two fundamental tasks in quantum information theory, data compression with quantum side information as well as randomness extraction against quantum side information. We characterize these tasks for general sources using…

Quantum Physics · Physics 2013-10-25 Marco Tomamichel , Masahito Hayashi

We analyse a quantum-like Bayesian Network that puts together cause/effect relationships and semantic similarities between events. These semantic similarities constitute acausal connections according to the Synchronicity principle and…

Artificial Intelligence · Computer Science 2015-08-28 Catarina Moreira , Andreas Wichert

The characterisation of quantum networks is fundamental to understanding how energy and information propagates through complex systems, with applications in control, communication, error mitigation and energy transfer. In this work, we…

Quantum Physics · Physics 2025-09-19 Conall J. Campbell , Matthew Mackinnon , Mauro Paternostro , Diana A. Chisholm