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Related papers: Time Averaged Quantum Dynamics and the Validity of…

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We present and compare two families of ensembles of random density matrices. The first, static ensemble, is obtained foliating an unbiased ensemble of density matrices. As criterion we use fixed purity as the simplest example of a useful…

Quantum Physics · Physics 2015-10-20 Carlos Pineda , Thomas H. Seligman

The time evolution of a bounded quantum system is considered in the framework of the orthogonal, unitary and symplectic circular ensembles of random matrix theory. For an $N$ dimensional Hilbert space we prove that in the large $N$ limit…

Mesoscale and Nanoscale Physics · Physics 2008-02-03 P. Leboeuf , G. Iacomelli

The quantum measurement axiom dictates that physical observables and in particular the Hamiltonian must be diagonalizable and have a real spectrum. For a time-independent Hamiltonian (with a discrete spectrum) these conditions ensure the…

Quantum Physics · Physics 2009-11-13 Ali Mostafazadeh

The ongoing discussion whether thermodynamic properties can be extracted from a (possibly approximate) quantum mechanical time evolution using time averages is fed with an instructive example. It is shown for the harmonic oscillator how the…

Statistical Mechanics · Physics 2009-10-31 J. Schnack

In a differential approach elaborated, we study the evolution of the parameters of Gaussian, mixed, continuous variable density matrices, whose dynamics are given by Hermitian Hamiltonians expressed as quadratic forms of the position and…

Quantum Physics · Physics 2020-05-26 Julio A. López-Saldívar , Margarita A. Man'ko , Vladimir I. Man'ko

We study the transport property of diffusion in a finite translationally invariant quantum subsystem described by a tight-binding Hamiltonian with a single energy band and interacting with its environment by a coupling in terms of…

Statistical Mechanics · Physics 2010-03-01 Massimiliano Esposito , Pierre Gaspard

Theories with Planck-scale deformed symmetries exhibit quantum time evolution in which purity of the density matrix is not preserved. In particular we show that the non-trivial structure of momentum space of these models is reflected in a…

High Energy Physics - Theory · Physics 2014-07-16 Michele Arzano

Transient stability is crucial to the reliable operation of power systems. Existing theories rely on the simplified electromechanical models, substituting the detailed electromagnetic dynamics of inductor and capacitor with their impedance…

Systems and Control · Electrical Eng. & Systems 2025-02-17 Xinyuan Jiang , Constantino M. Lagoa , Yan Li

If an experimentalist wants to decide which one of n possible Hamiltonians acting on an n dimensional Hilbert space is present, he can conjugate the time evolution by an appropriate sequence of known unitary transformations in such a way…

Quantum Physics · Physics 2009-11-07 Dominik Janzing , Thomas Beth

Effective field theories have often been applied to systems with deeply inelastic reactions that produce particles with large momenta outside the domain of validity of the effective theory. The effects of the deeply inelastic reactions have…

High Energy Physics - Phenomenology · Physics 2016-09-21 Eric Braaten , H. -W. Hammer , G. Peter Lepage

Dynamical mean-field theory (DMFT) is a useful tool to analyze models of strongly correlated fermions like the Hubbard model. In DMFT, the lattice of the model is replaced by a single impurity site embedded in an effective bath. The…

Quantum Physics · Physics 2026-03-27 Stefan Wolf , Martin Eckstein , Michael J. Hartmann

We consider a $\lambda \phi^4$ theory in Minkowski spacetime. We compute a "coarse grained effective action" by integrating out the field modes with wavelength shorter than a critical value. From this effective action we obtain the…

High Energy Physics - Theory · Physics 2008-11-26 Fernando Lombardo , Francisco Mazzitelli

The paper is devoted to the description a measurable time-interval (``proper time'') in the Hamiltonian version of general relativity with the Dirac-ADM metric. To separate the dynamical parameter of evolution from the space metric we use…

General Relativity and Quantum Cosmology · Physics 2014-11-17 L. N. Gyngazov , M. Pawlowski , V. N. Pervushin , V. I. Smirichinski

We show that the diagonal matrix elements of the effective Hamiltonian governing the time evolution in the subspace of states of an unstable particle and its antiparticle need not be equal at $t > t_{0}$ ($t_{0}$ is the instant of creation…

High Energy Physics - Phenomenology · Physics 2014-11-17 K. Urbanowski

We study the time evolution of the amount of entanglement generated by one dimensional spin-1/2 Ising-type Hamiltonians composed of many-body interactions. We investigate sets of states randomly selected during the time evolution generated…

Quantum Physics · Physics 2011-11-23 Yoshifumi Nakata , Mio Murao

Leveraging the techniques found in the literature on Quantum Equilibration for finite dimensional systems, we develop the theory of Quantum Equilibration for the case of infinite-dimensional systems, particularly the cases where the…

Quantum Physics · Physics 2025-03-13 Alberto Acevedo , Antonio Falco

We develop a Lie algebraic approach to systematically calculate the evolution operator of the generalized two-dimensional quadratic Hamiltonian with time-dependent coefficients. Although the development of the Lie algebraic approach…

Mathematical Physics · Physics 2016-01-21 V. G. Ibarra-Sierra , J. C. Sandoval-Santana , J. L. Cardoso , A. Kunold

Simulating the long-time evolution of Hamiltonian systems is limited by the small timesteps required for stable numerical integration. To overcome this constraint, we introduce a framework to learn Hamiltonian Flow Maps by predicting the…

The analysis of space-time data from complex, real-life phenomena requires the use of flexible and physically motivated covariance functions. In most cases, it is not possible to explicitly solve the equations of motion for the fields or…

Methodology · Statistics 2016-06-29 Dionissios T. Hristopulos , Ivi C. Tsantili

The presence of noise or the interaction with an environment can radically change the dynamics of observables of an otherwise isolated quantum system. We derive a bound on the speed with which observables of open quantum systems evolve.…