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Related papers: Quantum states as generalized classical ensembles

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Quantum cosmology is the quantum theory of the entire universe. Although strange at first sight, it is appropriate because (1) our world appears to be fundamentally quantum, (2) the classical description of gravity breaks down at…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Don N. Page

Description of nonclassicality of states has hitherto been through violation of Bell inequality and non-separability, with the latter being a stronger constraint. In this paper, we show that this can be further sharpened, by introducing the…

Quantum Physics · Physics 2015-06-18 H. M. Bharath , V. Ravishankar

A classical representation for quantum eigenstates of a particle bound in $\lambda z^{2m}$ $(\lambda >0, m=1,2,...)$ potentials is developed. It is represented by ensembles of classical trajectories with energy distributions that can take…

Quantum Physics · Physics 2025-10-22 Tasko Grozdanov , Evgeni Solov'ev

In a metric variable based Hamiltonian quantization, we give a prescription for constructing semiclassical matter-geometry states for homogeneous and isotropic cosmological models. These "collective" states arise as infinite linear…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Viqar Husain , Oliver Winkler

Frauchiger and Renner recently cast doubt on the universal applicability of Quantum Mechanics [1]. In the following, it is pointed out that their conclusion of one of three common-sense conditions, demanded for Quantum Mechanics, being…

General Physics · Physics 2020-04-23 Knud Thomsen

We consider the claim that decoherence explains the emergence of classicality in quantum systems, and conclude that it does not. We show that, given a randomly chosen universe composed of a variety of subsystems, some of which are…

Quantum Physics · Physics 2008-10-27 Steven Weinstein

The Belinski-Khalatnikov-Lifshitz scenario concerns the existence of generic singularity of general relativity. At the singularity, there is a breakdown of all known laws of physics. Quantization of this scenario leads, however, to regular…

General Relativity and Quantum Cosmology · Physics 2020-07-20 Włodzimierz Piechocki

We introduce a generalized phase-space representation of qubit systems called the BEADS representation which makes it possible to visualize arbitrary quantum states in an intuitive and an easy to grasp way. Our representation is exact,…

Quantum Physics · Physics 2025-03-06 Dennis Huber , Steffen J. Glaser

General relativity required the abandonment of Euclidean geometry. Here we show that quantum theory requires the abandonment of classical logic. We show that the Hilbert space representation of quantum theory is logically inevitable. There…

Quantum Physics · Physics 2021-11-23 Lars M. Johansen

In this talk, we discuss real-time thermalization dynamics of $\mathbf{Z}_2$ Lattice Gauge Theory in 2+1 spacetime dimensions. While classical thermalization is commonly associated with chaotic behavior, turbulence and universality, the…

High Energy Physics - Lattice · Physics 2021-11-03 Niklas Mueller , Torsten V. Zache , Robert Ott

The dimension of a quantum state is traditionally seen as the number of superposed distinguishable states in a given basis. We propose an absolute, i.e.~basis-independent, notion of dimensionality for ensembles of quantum states. It is…

Quantum Physics · Physics 2024-12-24 Alexander Bernal , Gabriele Cobucci , Martin J. Renner , Armin Tavakoli

It has become common practice to model large spin ensembles as an effective pseudospin with total angular momentum J = N x j, where j is the spin per particle. Such approaches (at least implicitly) restrict the quantum state of the ensemble…

Quantum Physics · Physics 2012-01-24 Ben Q. Baragiola , Bradley A. Chase , JM Geremia

Quantum fields are considered as generators of infinite-dimensional Clifford algebra $Cl(\infty)$, which can be either orthogonal (in case of fermions) or symplectic (in case of bosons). A generic quantum state can be expressed as a…

General Physics · Physics 2022-08-31 Matej Pavšič

We introduce a measure of ''quantumness'' for any quantum state in a finite dimensional Hilbert space, based on the distance between the state and the convex set of classical states. The latter are defined as states that can be written as a…

Quantum Physics · Physics 2015-05-18 Olivier Giraud , Petr A. Braun , Daniel Braun

The act of describing how a physical process changes a system is the basis for understanding observed phenomena. For quantum-mechanical processes in particular, the affect of processes on quantum states profoundly advances our knowledge of…

Quantum Physics · Physics 2017-10-20 Jen-Hsiang Hsieh , Shih-Hsuan Chen , Che-Ming Li

In this paper, the generalized coherent state for quantum systems with degenerate spectra is introduced. Then, the nonclassicality features and number-phase entropic uncertainty relation of two particular degenerate quantum systems are…

Quantum Physics · Physics 2015-03-17 G. R. Honarasa , M. K. Tavassoly , M. Hatami , R. Roknizadeh

The descriptions of the quantum realm and the macroscopic classical world differ significantly not only in their mathematical formulations but also in their foundational concepts and philosophical consequences. When and how physical systems…

Quantum Physics · Physics 2008-12-02 Johannes Kofler

We discuss the problem of the separation of total correlations in a given quantum state into entanglement, dissonance, and classical correlations using the concept of relative entropy as a distance measure of correlations. This allows us to…

Quantum Physics · Physics 2010-03-03 Kavan Modi , Tomasz Paterek , Wonmin Son , Vlatko Vedral , Mark Williamson

We argue that the conventional construction for quantum fields in curved spacetime has a grave drawback: It involves an uncountable set of physical field systems which are nonequivalent with respect to the Bogolubov transformations, and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Vladimir S. Mashkevich

We consider Hamiltonian systems of a certain class with unstable orbits moving to infinity. We prove a theorem showing that analogous quantum states do not exist. This theorem is applied to Schrodinger operators with potentials of degree…

Mathematical Physics · Physics 2009-11-13 I. Herbst , E. Skibsted