English
Related papers

Related papers: Quantum and classical bounds for two-state overlap…

200 papers

This paper is a review of our recent work on three notorious problems of non-relativistic quantum mechanics: realist interpretation, quantum theory of classical properties and the problem of quantum measurement. A considerable progress has…

Quantum Physics · Physics 2013-03-01 Petr Hajicek

We investigate the minimal proof for ruling out maximally $\psi-$epistemic interpretations of quantum theory, in which the indistinguishable nature of two quantum states is fully explained by the epistemic overlap of their corresponding…

Quantum Physics · Physics 2025-09-15 Sagnik Ray , Anubhav Chaturvedi , Debashis Saha

Quantum coherence is the most fundamental feature of quantum mechanics. The usual understanding of it depends on the choice of the basis, that is, the coherence of the same quantum state is different within different reference framework. To…

Quantum Physics · Physics 2017-04-17 Chang-shui Yu , Yi-ren Yang , Bao-qing Guo

We consider N quantum systems initially prepared in pure states and address the problem of unambiguously comparing them. One may ask whether or not all $N$ systems are in the same state. Alternatively, one may ask whether or not the states…

Quantum Physics · Physics 2014-11-18 Anthony Chefles , Erika Andersson , Igor Jex

We review canonical experiments on systems that have pushed the boundary between the quantum and classical worlds towards much larger scales, and discuss their unique features that enable quantum coherence to survive. Because the types of…

Quantum Physics · Physics 2015-06-19 Tristan Farrow , Vlatko Vedral

One of the best signatures of nonclassicality in a quantum system is the existence of correlations that have no classical counterpart. Different methods for quantifying the quantum and classical parts of correlations are amongst the more…

Quantum Physics · Physics 2012-11-29 Kavan Modi , Aharon Brodutch , Hugo Cable , Tomasz Paterek , Vlatko Vedral

We study the local indistinguishability problem of quantum states. By introducing an easily calculated quantity, non-commutativity, we present an criterion which is both necessary and sufficient for the local indistinguishability of a…

Quantum Physics · Physics 2014-09-17 Teng Ma , Ming-Jing Zhao , Yao-Kun Wang , Shao-Ming Fei

We identify ambiguities in the available frameworks for defining quantum, classical, and total correlations as measured by discordlike quantifiers. More specifically, we determine situations for which either classical or quantum…

Quantum Physics · Physics 2014-12-10 F. M. Paula , A. Saguia , Thiago R. de Oliveira , M. S. Sarandy

We derive and experimentally investigate a strong uncertainty relation valid for any $n$ unitary operators, which implies the standard uncertainty relation as a special case, and which can be written in terms of geometric phases. It is…

Entanglement is an useful resource because some global operations cannot be locally implemented using classical communication. We prove a number of results about what is and is not locally possible. We focus on orthogonal states, which can…

Quantum Physics · Physics 2009-11-07 Jonathan Walgate , Lucien Hardy

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement is explored for bi-partite and multi-partite pure and mixed states.…

Quantum Physics · Physics 2009-05-18 Tzu-Chieh Wei

A consistent description of interactions between classical and quantum systems is relevant to quantum measurement theory, and to calculations in quantum chemistry and quantum gravity. A solution is offered here to this longstanding problem,…

Quantum Physics · Physics 2009-11-11 Michael J. W. Hall , Marcel Reginatto

The quantum state overlap is the textbook measure of the difference between two quantum states. Yet, it is inadequate to compare the complex configurations of many-body systems. The problem is inherited by the widely employed quantum state…

Quantum Physics · Physics 2021-06-03 Davide Girolami , Fabio Anzà

A bipartite quantum state (for two systems in any dimensions) can be decomposed as a superposition of many components. For a superposition of more than two components we prove that there is a bound of the entanglement of the superposition…

Quantum Physics · Physics 2009-11-13 Yang Xiang , Shi-Jie Xiong , Fang-Yu Hong

We study quantum state estimation problems where the reference system with respect to which the state is measured should itself be treated quantum mechanically. In this situation, the difference between the system and the reference tends to…

Quantum Physics · Physics 2013-01-22 N. Gisin , S. Iblisdir

In the quantitative theory of quantum coherence, the amount of coherence for given states can be meaningfully discussed only when referring to a preferred basis. One of the objections to this quantification is that the amount of coherence…

Quantum Physics · Physics 2024-12-11 Zhi-Xiang Jin , Yuan-Hong Tao , Bing Yu , Shao-Ming Fei

The relativity of simultaneity together with definition of a quantum state's collapse result into experimental situations, where a multiple measurements can be taken on an uncollapsed quantum state. A quantum state's collapse space-time…

Quantum Physics · Physics 2024-02-07 Dalibor Javůrek

A novel no-go theorem is presented which sets a bound upon the extent to which '\Psi-epistemic' interpretations of quantum theory are able to explain the overlap between non-orthogonal quantum states in terms of an experimenter's ignorance…

Quantum Physics · Physics 2013-05-23 O. J. E. Maroney

Dimension witnesses allow one to test the dimension of an unknown physical system in a device-independent manner, that is, without placing assumptions about the functioning of the devices used in the experiment. Here we present simple and…

Quantum Physics · Physics 2013-04-16 Nicolas Brunner , Miguel Navascués , Tamás Vértesi

Quantum entangled states have shown distinguished features beyond any classical state. Many methods like quantum state tomography have been presented to verify entanglement. In this work, we aim to identify unknown entanglements with…

Quantum Physics · Physics 2021-11-29 Ming-Xing Luo , Shao-Ming Fei , Jing-Ling Chen