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Related papers: Classical Coding and the Cauchy-Schwarz Inequality

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Polar coding is a method for communication over noisy classical channels which is provably capacity-achieving and has an efficient encoding and decoding. Recently, this method has been generalized to the realm of quantum information…

Quantum Physics · Physics 2016-02-01 Christoph Hirche , Ciara Morgan , Mark M. Wilde

Dense coding with non-maximally entangled states has been investigated in many different scenarios. We revisit this problem for protocols adopting the standard encoding scheme. In this case, the set of possible classical messages cannot be…

Quantum Physics · Physics 2017-03-03 Roger Alfredo Kögler , Leonardo Neves

Quantum error correction will likely be essential for building a large-scale quantum computer, but it comes with significant requirements at the level of classical control software. In particular, a quantum error-correcting code must be…

Quantum Physics · Physics 2026-04-24 Ewan Murphy , Subhayan Sahu , Michael Vasmer

Cryptography with quantum states exhibits a number of surprising and counterintuitive features. In a 2002 work, Barnum et al. argue that these features imply that digital signatures for quantum states are impossible (Barnum et al., FOCS…

Quantum Physics · Physics 2021-12-22 Gorjan Alagic , Tommaso Gagliardoni , Christian Majenz

The extraction of classical degrees of freedom in quantum mechanics is studied in the stochastic variational method. By using this classicalization, a hybrid model constructed from quantum and classical variables (quantum-classical hybrids)…

Quantum Physics · Physics 2015-07-15 T. Koide

Quantum theory has found a new field of applications in the realm of information and computation during the recent years. This paper reviews how quantum physics allows information coding in classically unexpected and subtle nonlocal ways,…

Quantum Physics · Physics 2008-11-26 A. Galindo , M. A. Martin-Delgado

Although classical mechanics and quantum mechanics are separate disciplines, we live in a world where Planck's constant \hbar>0, meaning that the classical and quantum world views must actually {\it coexist}. Traditionally, canonical…

Quantum Physics · Physics 2015-06-04 John R. Klauder

This work will incorporate a few related tools for addressing the conceptual difficulties arising from sewing together classical and quantum mechanics: deterministic operators, weak measurements and post-selection. Weak Measurement, based…

Quantum Physics · Physics 2016-12-21 Eliahu Cohen , Yakir Aharonov

In the quantum compression scheme proposed by Schumacher, Alice compresses a message that Bob decompresses. In that approach, there is some probability of failure and, even when successful, some distortion of the state. For sufficiently…

Quantum Physics · Physics 2024-03-01 Jack Weinberg , Avijit Mandal , Henry D. Pfister

Predicting properties of complex, large-scale quantum systems is essential for developing quantum technologies. We present an efficient method for constructing an approximate classical description of a quantum state using very few…

Quantum Physics · Physics 2021-04-20 Hsin-Yuan Huang , Richard Kueng , John Preskill

We define a large class of quantum sources and prove a quantum analog of the asymptotic equipartition property. Our proof relies on using local measurements on the quantum source to obtain an associated classical source. The classical…

Quantum Physics · Physics 2009-10-28 Christopher King , Andrzej Lesniewski

In this paper, we show that a result precisely analogous to the traditional quantum no-cloning theorem holds in classical mechanics. This classical no-cloning theorem does not prohibit classical cloning, we argue, because it is based on a…

Mathematical Physics · Physics 2011-12-30 Aaron Fenyes

Soon after the dawn of quantum error correction, DiVincenzo and Peres observed that stabilizer codewords could give rise to simple proofs of quantumness via contextuality. This discovery can be recast in the language of nonlocal games:…

Quantum Physics · Physics 2025-12-19 Wanbing Zhao , H. W. Shawn Liew , Wen Wei Ho , Chunxiao Liu , Vir B. Bulchandani

The fundamental problem of the transition from quantum to classical physics is usually explained by decoherence, and viewed as a gradual process. The study of entanglement, or quantum correlations, in noisy quantum computers implies that in…

Quantum Physics · Physics 2016-09-08 Dorit Aharonov

We study the hardness of the problem of finding the distance of quantum error-correcting codes. The analogous problem for classical codes is known to be NP-hard, even in approximate form. For quantum codes, various problems related to…

Quantum Physics · Physics 2023-11-07 Upendra Kapshikar , Srijita Kundu

We investigate practical finite-blocklength classical-quantum channel coding over the quantum amplitude damping channel (ADC), aiming to transmit classical information reliably through quantum outputs. Our findings indicate that for any…

Information Theory · Computer Science 2025-09-19 Tamás Havas , Hsuan-Yin Lin , Eirik Rosnes , Ching-Yi Lai

One of the crucial differences between mathematical models of classical and quantum mechanics is the use of the tensor product of the state spaces of subsystems as the state space of the corresponding composite system. (To describe an…

General Physics · Physics 2010-08-03 Andrei Khrennikov

Heisenberg's uncertainty principle is often cited as an example of a "purely quantum" relation with no analogue in the classical limit where $\hbar \to 0$. However, this formulation of the classical limit is problematic for many reasons,…

Quantum Physics · Physics 2021-02-23 Viola Gattus , Sotirios Karamitsos

We consider the classical correlations that two observers can extract by measurements on a bipartite quantum state, and we discuss how they are related to the quantum mutual information of the state. We show with several examples how…

Quantum Physics · Physics 2009-09-19 Shengjun Wu , Uffe V. Poulsen , Klaus Mølmer

Classical and quantum information theory are simply explained. To be more specific it is clarified why Shannon entropy is used as measure of classical information and after a brief review of quantum mechanics it is possible to demonstrate…

Quantum Physics · Physics 2007-05-23 Nikolaos P. Papadakos