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Related papers: Brownian motion in superfluid $^4$He

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We study the motion of a slow quantum impurity in one-dimensional environments focusing on systems of strongly interacting bosons and weakly interacting fermions. While at zero temperature the impurity motion is frictionless, at low…

Quantum Gases · Physics 2020-03-11 Aleksandra Petkovic

The diffusion coefficient--a measure of dissipation, and the entropy--a measure of fluctuation are found to be intimately correlated in many physical systems. Unlike the fluctuation dissipation theorem in linear response theory, the…

Statistical Mechanics · Physics 2021-03-25 Yi Liao , Xiao-Bo Gong

The Brownian motion of a test particle interacting with a quantum scalar field in the presence of a perfectly reflecting boundary is studied in (1 + 1)-dimensional flat spacetime. Particularly, the expressions for dispersions in velocity…

Quantum Physics · Physics 2014-09-02 V. A. De Lorenci , E. S. Moreira , M. M. Silva

In ultracold gases many experiments use atom imaging as a basic observable. The resulting image is averaged over a number of realizations and mostly only this average is used. Only recently the noise has been measured to extract physical…

Statistical Mechanics · Physics 2015-05-13 G. E. Astrakharchik , R. Combescot , L. P. Pitaevskii

We have measured the interaction between superfluid $^3$He-B and a micro-machined goalpost-shaped device at temperatures below $0.2\,T_c$. The measured damping follows well the theory developed for vibrating wires, in which the Andreev…

Fluctuating hydrodynamics based techniques have been developed in recent years for the simulation of Brownian motion of particles. These mesoscale simulation tools are viable approaches for problems where molecular dynamics simulations may…

Fluid Dynamics · Physics 2014-02-11 Yong Chen , Neelesh A. Patankar

A stochastic Langevin equation is derived, describing the thermal motion of a molecule immersed in a rested fluid of identical molecules. The fluctuation-dissipation theorem is proved and a number of correlation characteristics of the…

Statistical Mechanics · Physics 2014-11-11 Roumen Tsekov

A meshfree Lagrangian method for the fluctuating hydrodynamic equations (FHEs) with fluid-structure interactions is presented. Brownian motion of the particle is investigated by direct numerical simulation of the fluctuating hydrodynamic…

Dynamical Systems · Mathematics 2015-12-15 Anamika Pandey , Steffen Hardt , Axel Klar , Sudarshan Tiwari

A fully quantum treatment of Einstein's Brownian motion is given, showing in particular the role played by the two original requirements of translational invariance and connection between dynamics of the Brownian particle and atomic nature…

Quantum Physics · Physics 2007-05-23 Francesco Petruccione , Bassano Vacchini

We present the Markovian quantum master equation describing rotational decoherence, friction, diffusion, and thermalization of planar, linear, and asymmetric rotors in contact with a thermal environment. It describes how an arbitrary…

Quantum Physics · Physics 2018-07-27 Benjamin A. Stickler , Björn Schrinski , Klaus Hornberger

Quantum Brownian motion in the strong friction limit is studied based on the exact path integral formulation of dissipative systems. In this limit the time-nonlocal reduced dynamics can be cast into an effective equation of motion, the…

Statistical Mechanics · Physics 2009-11-10 Joachim Ankerhold , Hermann Grabert , Philip Pechukas

The classical theory of Brownian dynamics follows from coarse-graining the underlying linearized fluctuating hydrodynamics of the solvent. We extend this procedure to globally non-isothermal conditions, requiring only a local thermal…

Statistical Mechanics · Physics 2016-04-06 G. Falasco , K. Kroy

Brownian motion (BM) is pivotal in natural science for the stochastic motion of microscopic droplets. In this study, we investigate BM driven by thermal composition noise at sub-micro scales, where inter-molecular diffusion and surface…

Fluid Dynamics · Physics 2025-02-26 Haodong Zhang , Fei Wang , Lorenz Ratke , Britta Nestler

Brownian motion has played important roles in many different fields of science since its origin was first explained by Albert Einstein in 1905. Einstein's theory of Brownian motion, however, is only applicable at long time scales. At short…

Statistical Mechanics · Physics 2013-09-03 Tongcang Li , Mark G. Raizen

The scattering of atoms and rotons at the free surface of superfluid 4He is studied in the framework of linearised time dependent mean field theory. The phenomenological Orsay-Trento density functional is used to solve numerically the…

Condensed Matter · Physics 2009-10-28 F. Dalfovo , A. Fracchetti , A. Lastri , L. Pitaevskii , S. Stringari

We analyze the classical and quantized center-of-mass motion of a polarizable particle interacting with the fluctuations of the electromagnetic (EM) field in the presence of a medium. As a polarizable particle is immersed in a thermal…

Quantum Physics · Physics 2024-08-29 Clemens Jakubec , Christopher Jarzynski , Kanu Sinha

In the last ten years, a number of ``Conventional Fluctuation Theorems'' have been derived for systems with deterministic or stochastic dynamics, in a transient or in a non-equilibrium stationary state. These theorems gave explicit…

Statistical Mechanics · Physics 2007-05-23 R. van Zon , E. G. D. Cohen

We analyse the impact of temperature on the diffusion coefficient of an inertial Brownian particle moving in a symmetric periodic potential and driven by a symmetric time-periodic force. Recent studies have revealed the low friction regime…

Statistical Mechanics · Physics 2023-06-28 I. G. Marchenko , V. Aksenova , I. I. Marchenko , J. Łuczka , J. Spiechowicz

We analyze quantal Brownian motion in $d$ dimensions using the unified model for diffusion localization and dissipation, and Feynman-Vernon formalism. At high temperatures the propagator possess a Markovian property and we can write down an…

Condensed Matter · Physics 2009-10-31 Doron Cohen

Despite recent tremendous progress in optical imaging and metrology, the resolution gap between atomic scale transmission electron microscopy and optical techniques has not been closed. Is optical imaging and metrology of nanostructures…