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Related papers: Hunting for the Quantum Cheshire Cat

200 papers

We introduce a semidefinite programming algorithm to find the minimal quantum Fisher information compatible with an arbitrary dataset of mean values. This certification task allows one to quantify the resource content of a quantum system…

The Cheshire cat principle states that hadronic observables at low energy do not distinguish between hard (quark) or soft (meson) constituents. As a result, the delineation between hard/soft (bag radius) is like the Cheshire cat smile in…

High Energy Physics - Theory · Physics 2016-12-21 Holger Bech Nielsen , Ismail Zahed

A fundamental principle of quantum theory, clearly manifested in the two-slit experiment, is that for any alternatives that cannot be distinguished by measurement physical predictions are obtained by summation of their amplitudes. In…

Quantum Physics · Physics 2009-07-17 C. Anastopoulos , N. Savvidou

Working entirely within the Schroedinger paradigm, meaning wavefunction only, I present a modification of his theory that prevents formation of macroscopic dispersion (MD; "cats"). The proposal is to modify the Hamiltonian based on a method…

Quantum Physics · Physics 2017-10-11 W. David Wick

Baryons in finite nuclei, nuclear matter and dense compact-star matter are described in terms of Cheshire Cat for QCD. A potential conceptual link, admittedly short in mathematical rigor, between their manifestations is made by what's…

Nuclear Theory · Physics 2024-10-15 Mannque Rho

Superposed coherent states are central to quantum technologies, yet their reliable identification remains a challenge, especially in noisy or resource-constrained settings. We introduce a novel, directly measurable criterion for detecting…

Quantum Physics · Physics 2026-04-27 Šimon Bräuer , Jan Provazník , Vojtěch Kala , Petr Marek

We obtain analytical lower bounds on the concurrence of bipartite quantum systems in arbitrary dimensions related to the violation of separability conditions based on local uncertainty relations and on the Bloch representation of density…

Quantum Physics · Physics 2009-11-13 Julio I. de Vicente

The rapid developments of Quantum Information Science (QIS) have opened up new avenues for exploring fundamental physics. Quantum nonlocality, a key aspect for distinguishing quantum information from classical one, has undergone extensive…

High Energy Physics - Phenomenology · Physics 2024-02-27 Sihao Wu , Chen Qian , Yang-Guang Yang , Qun Wang

There has been a surge of progress in recent years in developing algorithms for testing and learning quantum states that achieve optimal copy complexity. Unfortunately, they require the use of entangled measurements across many copies of…

Quantum Physics · Physics 2020-04-20 Sebastien Bubeck , Sitan Chen , Jerry Li

We explore the relation between entanglement entropy of quantum many body systems and the distribution of corresponding, properly selected, observables. Such a relation is necessary to actually measure the entanglement entropy. We show that…

Statistical Mechanics · Physics 2009-11-11 Israel Klich , Gil Refael , Alessandro Silva

We present a generalized partial transposition separability criterion for the density matrix of a multipartite quantum system. This criterion comprises as special cases the famous Peres-Horodecki criterion and the recent realignment…

Quantum Physics · Physics 2009-11-07 Kai Chen , Ling-An Wu

We formulate an entanglement criterion using Peres-Horodecki positive partial transpose operations combined with the Schr\"odinger-Robertson uncertainty relation. We show that any pure entangled bipartite and tripartite state can be…

Quantum Physics · Physics 2009-11-13 J. Gillet , T. Bastin , G. S. Agarwal

The `Schr\"odinger's cat' thought experiment highlights the counterintuitive facet of quantum theory that entanglement can exist between microscopic and macroscopic systems, producing a superposition of distinguishable states like the…

Quantum entanglement serves as a fundamental resource in quantum information theory. This paper presents a comprehensive framework of separability criteria for detecting bipartite and multipartite entanglements. We construct a novel…

Quantum Physics · Physics 2026-05-19 Linwei Li , Chunlin Yang , Hongmei Yao , Aimin Xu , Zhaobing Fan , Shao-Ming Fei

Chi-squared tests for lack of fit are traditionally employed to find evidence against a hypothesized model, with the model accepted if the Karl Pearson statistic comparing observed and expected numbers of observations falling within cells…

Statistics Theory · Mathematics 2021-12-20 Robert G. Staudte

Experimental progress with meso- and macroscopic quantum states (i.e., general Schrodinger-cat states) was recently accompanied by theoretical proposals on how to measure the merit of these efforts. So far, experiment and theory were…

Quantum Physics · Physics 2017-03-21 Florian Fröwis

Entanglement, or quantum inseparability, is a crucial resource in quantum information applications, and therefore the experimental generation of separated yet entangled systems is of paramount importance. Experimental demonstrations of…

Quantum Physics · Physics 2009-11-07 M. G. Raymer , A. C. Funk , B. C. Sanders , H. de Guise

Given a quantum state in the finite-dimensional Hilbert space $ \C^n $, the range of possible values of a quantum observable is usually identified with the discrete spectrum of eigenvalues of a corresponding Hermitian matrix. Here any such…

Quantum Physics · Physics 2025-09-29 Peter J. Hammond

For nearly 100 years, the paradox of Schr\"odinger's Cat has remained unresolved. Why does the world we live in appear classical despite being composed of quantum particles governed by the Schr\"odinger wave equation? Lajos Di\'osi and…

Quantum Physics · Physics 2024-02-06 James Tagg , William Reid , Daniel Carlin

This PHD thesis is concerned with uncertainty relations in quantum probability theory, state estimation in quantum stochastics, and natural bundles in differential geometry. After some comments on the nature and necessity of decoherence in…

Differential Geometry · Mathematics 2010-11-15 Bas Janssens