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An unstable quantum state generally decays following an exponential law, as environmental decoherence is expected to prevent the decay products from recombining to reconstruct the initial state. Here we show the existence of deviations from…

Quantum Physics · Physics 2017-10-02 M. Beau , J. Kiukas , I. L. Egusquiza , A. del Campo

Classical gravitational evolution admits an elegant and compact re-expression in terms of gauge covariant generalizations of Lie derivatives with respect to a spatial phase space dependent $su(2)$ valued vector field called the Electric…

General Relativity and Quantum Cosmology · Physics 2022-11-28 Madhavan Varadarajan

Neutrinos lose coherence as they propagate, which leads to the fading away of oscillations. In this work, we model neutrino decoherence induced in open quantum systems from their interaction with the environment. We first present two…

High Energy Physics - Phenomenology · Physics 2021-04-19 Bin Xu

Special relativity beyond its basic treatment can be inaccessible, in particular because introductory physics courses typically view special relativity as decontextualized from the rest of physics. We seek to place special relativity back…

Classical Physics · Physics 2026-04-14 Gerd Wagner , Matthew W. Guthrie

It is shown that the recently proposed quantum analogue of classical energy equipartition theorem for two paradigmatic, exactly solved models (i.e., a free Brownian particle and a dissipative harmonic oscillator) also holds true for all…

Quantum Physics · Physics 2021-02-05 Jerzy Łuczka

The classical Lagrange formalism is generalized to the case of arbitrary stationary (but not necessarily conservative) dynamical systems. It is shown that the equations of motion for such systems can be derived in the standard ways from the…

Classical Physics · Physics 2022-12-26 Alex Ushveridze

We study the dynamics of quantum and classical correlations in the presence of nondissipative decoherence. We discover a class of initial states for which the quantum correlations, quantified by the quantum discord, are not destroyed by…

Quantum Physics · Physics 2015-05-18 L. Mazzola , J. Piilo , S. Maniscalco

It has recently been shown that small quantum subsystems generically equilibrate, in the sense that they spend most of the time close to a fixed equilibrium state. This relies on just two assumptions: that the state is spread over many…

Quantum Physics · Physics 2015-05-30 Anthony J. Short , Terence C. Farrelly

At the heart of quantum technology development is the control of quantum systems at the level of individual quanta. Mathematically, this is realised through the study of Hamiltonians and the use of methods to solve the dynamics of quantum…

Quantum Physics · Physics 2022-10-24 Sofia Qvarfort , Igor Pikovski

We investigate conservation laws in the quantum mechanics of closed systems. We review an argument showing that exact decoherence implies the exact conservation of quantities that commute with the Hamiltonian including the total energy and…

General Relativity and Quantum Cosmology · Physics 2009-10-22 James B. Hartle , Raymond Laflamme , Donald Marolf

Fractional mechanics describes both conservative and non-conservative systems. The fractional variational principles gained importance in studying the fractional mechanics and several versions are proposed. In classical mechanics the…

Mathematical Physics · Physics 2007-08-14 Dumitru Baleanu , Sami I. Muslih , Eqab M. Rabei

We investigate the non-equilibrium quantum dynamics and thermodynamics of free fermions suddenly coupled to a localized defect in a one-dimensional harmonic trap. This setup realizes a quantum quench transformation that gives rise to the…

Quantum Gases · Physics 2026-01-26 Beatrice Donelli , Gabriele De Chiara , Francesco Scazza , Stefano Gherardini

Time and again, non-conventional forms of Lagrangians with non-quadratic velocity dependence have found attention in the literature. For one thing, such Lagrangians have deep connections with several aspects of nonlinear dynamics including…

Mathematical Physics · Physics 2024-07-09 Bijan Bagchi , Aritra Ghosh , Miloslav Znojil

The fundamental difference between closed and open quantum dynamics lies in their environmental interaction: closed systems are perfectly isolated and evolve reversibly under unitary Hamiltonian dynamics, whereas open systems continuously…

Quantum Physics · Physics 2026-04-21 Zhong-Xia Shang , Daniel Stilck França

Effective Lagrangians, including those that are spontaneously broken, contain redundant terms. It is shown that the classical equations of motion may be used to simplify the effective Lagrangian, even when quantum loops are to be…

High Energy Physics - Phenomenology · Physics 2009-10-22 C. Arzt

In this paper, a new approach for constructing Lagrangians for driven and undriven linearly damped systems is proposed, by introducing a redefined time coordinate and an associated coordinate transformation to ensure that the resulting…

Quantum Physics · Physics 2021-09-22 Matthew J. Blacker , David L. Tilbrook

The low-energy and low-momentum dynamics of systems with a spontaneously broken continuous symmetry is dominated by the ensuing Nambu-Goldstone bosons. It can be conveniently encoded in a model-independent effective field theory whose…

High Energy Physics - Phenomenology · Physics 2014-08-19 Jens O. Andersen , Tomas Brauner , Christoph P. Hofmann , Aleksi Vuorinen

Open quantum systems weakly coupled to the environment are modeled by completely positive, trace preserving semigroups of linear maps. The generators of such evolutions are called Lindbladians. In the setting of quantum many-body systems on…

Quantum Physics · Physics 2015-04-29 Toby S. Cubitt , Angelo Lucia , Spyridon Michalakis , David Perez-Garcia

The present work shows that through a suitable change of variables relativistic dynamics can be mapped to light propagation in a non-homogeneous medium. A particle's trajectory through the modified space-time is thus formally equivalent to…

Optics · Physics 2007-05-23 J. B. Almeida

We explore the relaxation dynamics of quantum many-body systems that undergo purely dissipative dynamics through non-classical jump operators that can establish quantum coherence. Our goal is to shed light on the differences in the…

Quantum Physics · Physics 2015-06-22 Beatriz Olmos , Igor Lesanovsky , Juan P. Garrahan