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In the Coulomb blockade regime of a ballistic quantum dot, the distribution of conductance peak spacings is well known to be incorrectly predicted by a single-particle picture; instead, matrix element fluctuations of the residual electronic…

Mesoscale and Nanoscale Physics · Physics 2009-08-14 L. Kaplan

The vast majority of the literature dealing with quantum dynamics is concerned with linear evolution of the wave function or the density matrix. A complete dynamical description requires a full understanding of the evolution of measured…

Descriptions of molecular systems usually refer to two distinct theoretical frameworks. On the one hand the quantum pure state, i.e. the wavefunction, of an isolated system which is determined to calculate molecular properties and to…

Statistical Mechanics · Physics 2011-03-17 Barbara Fresch , Giorgio J. Moro

Subsystems of composite quantum systems are described by reduced density matrices, or quantum marginals. Important physical properties often do not depend on the whole wave function but rather only on the marginals. Not every collection of…

Quantum Physics · Physics 2014-10-31 Michael Walter

Energy and momentum of the elementary excitations become independent variables in medium: energy and momentum statistical distributions are not identical. The momentum distribution and not the energy distribution is relevant for barrier…

Nuclear Theory · Physics 2016-11-23 M. Coraddu , M. Lissia , G. Mezzorani , P. Quarati

We construct and explore a family of states for quantum systems in contact with two or more heath reservoirs. The reservoirs are described by equilibrium distributions. The interaction of each reservoir with the bulk of the system is…

Statistical Mechanics · Physics 2022-05-03 Mihail Mintchev

We show how the momentum distribution of gaseous Bose--Einstein condensates can be shaped by applying a sequence of standing-wave laser pulses. We present a theory, whose validity for was demonstrated in an earlier experiment [L.\ Deng, et…

Quantum Gases · Physics 2010-12-17 Mark Edwards , Brandon Benton , Jeffrey Heward , Charles W. Clark

A quantum system's state is identified with a density matrix. Though their probabilistic interpretation is rooted in ensemble theory, density matrices embody a known shortcoming. They do not completely express an ensemble's physical…

Quantum Physics · Physics 2021-06-30 Fabio Anza , James P. Crutchfield

A diffusion process for charge distributions in a phase space is examined. The corresponding charge moves in a force field and under an action of a random field. There are the diffusion motions for coordinates and for momenta. In our model,…

Mathematical Physics · Physics 2008-03-19 E. M. Beniaminov

When non-solid matter (e.g., liquids or gas) is under constant volume V and density rho (e.g., in rigid box), spatial positions for their constituents are restricted by these conditions. We recently focus on the role of constraint in…

Materials Science · Physics 2016-11-07 Koretaka Yuge , Makoto Murata

An overview is presented of transverse momentum distributions of particles at the LHC using the Tsallis distribution. The use of a thermodynamically consistent form of this distribution leads to an excellent description of charged and…

High Energy Physics - Phenomenology · Physics 2013-10-02 M. D. Azmi , J. Cleymans

Quantum turbulence can be generated in superfluid helium either thermally (by applying a heat flux, as in thermal counterflow) or mechanically (by stirring the liquid). By modelling the superfluid vortex lines as reconnecting space curves…

Other Condensed Matter · Physics 2015-06-04 A. W. Baggaley , L. K. Sherwin , C. F. Barenghi , Y. A. Sergeev

Ferrofluids show unusual hydrodynamic effects due to the magnetic nature of their constituents. For increasing magnetization a classical ferrofluid undergoes a Rosensweig instability and creates self-organized ordered surface structures or…

Understanding the physics of non-equilibrium systems remains as one of the major open questions in statistical physics. This problem can be partially handled by investigating macroscopic fluctuations of key magnitudes that characterise the…

Soft Condensed Matter · Physics 2016-11-17 A. Lasanta , Pablo I. Hurtado , A. Prados

With this work we investigate the stationary nonequilibrium density matrix of current carrying nonequilibrium steady states of in-between quantum systems that are connected to reservoirs. We describe the analytical procedure to obtain the…

Statistical Mechanics · Physics 2015-05-28 Abhishek Dhar , Keiji Saito , Peter Hanggi

The standard assumption for the equilibrium microcanonical state in quantum mechanics, that the system must be in one of the energy eigenstates, is weakened so as to allow superpositions of states. The weakened form of the microcanonical…

Quantum Physics · Physics 2007-05-23 Dorje C Brody , Daniel W Hook , Lane P Hughston

The apparent symmetry between energy and momentum found in all covariant descriptions of neutrino oscillations is destroyed in the neutrino detector, a quantum mechanical system described by a density matrix diagonal in energy but not in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harry J. Lipkin

Turbulence is an intriguing non-equilibrium state, which originates from fluid mechanics and has far-reaching consequences in the description of climate physics, the characterization of quantum hydrodynamics, and the understanding of cosmic…

The possibility that disorder may stabilize a superfluid phase of para-hydrogen in two dimensions is investigated theoretically by means of Quantum Monte Carlo simulations. We model disorder using a random distribution of scatterers, and…

Other Condensed Matter · Physics 2008-10-15 Joseph Turnbull , Massimo Boninsegni

The reformulation of field theory in which self-energy processes are no longer present [Annals of Physics, {\bf311} (2004), 314.], [ Progr. Theor. Phys., {\bf 109} (2003), 881.], [Trends in Statistical Physics {\bf 3} (2000), 115.] provides…

High Energy Physics - Theory · Physics 2007-05-23 Michel de Haan