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Related papers: Observing the Spontaneous Breakdown of Unitarity

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Kinematical and dynamical mechanisms leading to the spontaneous breaking of space-time symmetries are described. The symmetries affected are space and time translations, space rotations, scale and conformal transformations. Applications are…

High Energy Physics - Theory · Physics 2015-03-13 Eliezer Rabinovici

The deterministic and time-reversal symmetric dynamics of isolated quantum systems is at odds with irreversible equilibration observed in generic thermodynamic systems. Standard approaches at a reconciliation employ subjective restrictions…

Quantum Physics · Physics 2025-11-07 Aritro Mukherjee

We apply the many-particle Schr\"{o}dinger-Newton equation, which describes the co-evolution of an many-particle quantum wave function and a classical space-time geometry, to macroscopic mechanical objects. By averaging over motions of the…

General Relativity and Quantum Cosmology · Physics 2013-05-01 Huan Yang , Haixing Miao , Da-Shin Lee , Bassam Helou , Yanbei Chen

We investigate the influence of spontaneous symmetry breaking on the decoherence of a many-particle quantum system. This decoherence process is analyzed in an exactly solvable model system that is known to be representative of symmetry…

Strongly Correlated Electrons · Physics 2009-11-10 Jasper van Wezel , Jeroen van den Brink , Jan Zaanen

In this paper an overview of some recent developments on the classical limit and spontaneous symmetry breaking (SSB) in algebraic quantum theory is given. In such works, based on the theory of $C^*$-algebras, the concept of the classical…

Mathematical Physics · Physics 2023-03-29 Christiaan J. F. van de Ven

In this paper, the emergence of macroscopic-scale pseudo time-irreversibility is studied in the closed classical many-body system of pair interacting particles. First, exact continuum equations are derived to the Hamiltonian dynamics…

Statistical Mechanics · Physics 2022-02-04 Gyula I. Toth

Spontaneous symmetry breaking has revolutionized the understanding in numerous fields of modern physics. Here, we theoretically demonstrate the spontaneous time-reversal symmetry breaking in a cavity quantum electrodynamics system in which…

Quantum Physics · Physics 2018-08-01 Yu-Kun Lu , Pai Peng , Qi-Tao Cao , Da Xu , Jan Wiersig , Qihuang Gong , Yun-Feng Xiao

The dynamical status of isolated quantum systems, partly due to the linearity of the Schrodinger equation is unclear: Conventional measures fail to detect chaos in such systems. However, when quantum systems are subjected to observation --…

Quantum Physics · Physics 2009-11-10 Salman Habib , Kurt Jacobs , Kosuke Shizume

Ever since the advent of quantum mechanics, it has been clear that the atoms composing matter do not obey Newton's laws. Instead, their behavior is described by the Schroedinger equation. Surprisingly though, until recently, no clear…

Quantum Physics · Physics 2007-05-23 Tanmoy Bhattacharya , Salman Habib , Kurt Jacobs

We analyse the nature of spontaneous symmetry breaking in complex quantum systems by investigating the long-standing conjecture that the maximally symmetry-breaking quantum ground states are the most classical ones corresponding to a…

Statistical Mechanics · Physics 2016-04-22 M. Cianciaruso , S. M. Giampaolo , L. Ferro , W. Roga , G. Zonzo , M. Blasone , F. Illuminati

In a quantum many-body system coupled to the environment, its steady state can exhibit spontaneous symmetry breaking when a control parameter exceeds a critical value. In this study, we consider spontaneous symmetry breaking in non-steady…

Quantum Physics · Physics 2023-05-12 Taiki Haga

One of the central foundational problems in quantum mechanics is the inability of Schr\"odinger's unitary time evolution to describe measurement of a quantum state. Recent developments in models of spontaneous unitarity violation (SUV)…

Quantum Physics · Physics 2025-01-07 Dakshansh Chawda

Based on new experiments about the "macroscopic Schrodinger's cat state" etc., a self-consistent interpretation on quantum mechanics is presented from the new point of view combining physics, philosophy and mathematics together.

High Energy Physics - Phenomenology · Physics 2007-05-23 Guang-jiong Ni

We discuss the notion of quantum mechanical coherence in its connection with time evolution and stationarity. The transition from coherence to decoherence is examined in terms of an equation for the time dependence of the density matrix. It…

Quantum Physics · Physics 2007-05-23 L. Stodolsky

Quantum mechanics is an extremely successful theory that agrees with every experiment. However, the principle of linear superposition, a central tenet of the theory, apparently contradicts a commonplace observation: macroscopic objects are…

Quantum Physics · Physics 2015-03-20 Angelo Bassi , Kinjalk Lochan , Seema Satin , Tejinder P. Singh , Hendrik Ulbricht

Quantum mechanics marks a radical departure from the classical understanding of Nature, fostering an inherent randomness which forbids a deterministic description; yet the most fundamental departure arises from something different. As shown…

Developing an earlier proposal (Ne'eman, Damnjanovic, etc), we show herein that there is a Landau continuous phase transition from the exact quantum dynamics to the effectively classical one, occurring via spontaneous superposition breaking…

Quantum Physics · Physics 2007-05-23 Vladan Pankovic , Tristan Hubsch , Milan Predojevic , Miodrag Krmar

Light is a precious tool to probe matter, as it captures microscopic and macroscopic information on the system. We here report on the transition from a thermal (classical) to a spontaneous emission (quantum) mechanism for the loss of light…

It is shown how classical states, meant as states representing a classical object, can be produced in the thermodynamic limit, retaining the unitary evolution of quantum mechanics. Besides, using a simple model of a single spin interacting…

Quantum Physics · Physics 2011-08-04 Marco Frasca

A two boundary quantum mechanics without time ordered causal structure is advocated as consistent theory. The apparent causal structure of usual "near future" macroscopic phenomena is attributed to a cosmological asymmetry and to rules…

Quantum Physics · Physics 2017-03-08 Fritz W. Bopp