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Related papers: Quantum Transport Equations for a Scalar Field

200 papers

We describe electrical transport in ideal single-layer graphene at zero applied bias. There is a crossover from collisionless transport at frequencies larger than k_B T/hbar (T is the temperature) to collision-dominated transport at lower…

Mesoscale and Nanoscale Physics · Physics 2008-08-14 Lars Fritz , Joerg Schmalian , Markus Mueller , Subir Sachdev

The transport coefficients of a dilute classical gas in the presence of a drag force proportional to the velocity of the particle are determined from the Boltzmann equation. The viscous drag force could model the friction of solid particles…

Statistical Mechanics · Physics 2015-06-18 José Carlos Pérez-Fuentes , Vicente Garzó

Traditional theories of electron transport in crystals are based on the Boltzmann equation and do not capture physics arising from quantum coherence. We introduce a transport formalism based on ''orbital Wigner functions'', which accurately…

We study quantum phase coherence and weak localization (WL) in disordered metals with restricted back-scattering and phenomenologically formulate a large class of unconventional transport mechanisms as modified diffusion processes not…

Disordered Systems and Neural Networks · Physics 2010-08-06 Shimul Akhanjee

In this paper we consider a scalar transport equation with constant coefficients on domains with discrete space and continuous, discrete or general time. We show that on all these underlying domains solutions of the transport equation can…

Analysis of PDEs · Mathematics 2012-01-05 Petr Stehlík , Jonáš Volek

Radiative transfer in curved spacetimes has become increasingly important to understanding high-energy astrophysical phenomena and testing general relativity in the strong field limit. The equations of radiative transfer are physically…

Astrophysics · Physics 2009-11-13 Avery E. Broderick

The semiclassical Boltzmann equation is widely used to study transport effects. However, being semiclassical and borrowing heavily from classical mechanics, the formalism calls for verification from the perspective of quantum mechanics.…

Mesoscale and Nanoscale Physics · Physics 2025-08-05 Da Ma , Zhi-Fan Zhang , Hua Jiang , X. C. Xie

Within QED, we examine several issues related to constructing a parton-model-based QCD transport theory. We rewrite the QED analog of the parton model, the Weizsaecker-Williams Approximation, entirely in terms of phase-space quantities and…

Nuclear Theory · Physics 2011-07-19 David A. Brown , Pawel Danielewicz

The cross-over from coherent to incoherent exciton transport in disordered polymer films is studied by computationally solving a modified form of the Redfield equation for the exciton density matrix. This theory models quantum mechanical…

Chemical Physics · Physics 2007-05-23 William Barford , Christopher D P Duffy

We systematically derive the quantum kinetic equation in full phase space for any quadratic hamiltonian of bosonic fields, including in the absence of translational invariance. This enables the treatment of boundaries, inhomogeneous systems…

Strongly Correlated Electrons · Physics 2025-04-22 Léo Mangeolle , Lucile Savary , Leon Balents

A linear Boltzmann equation is derived in the Boltzmann-Grad scaling for the deterministic dynamics of many interacting particles with random initial data. We study a Rayleigh gas where a tagged particle is undergoing hard-sphere collisions…

Analysis of PDEs · Mathematics 2017-11-29 Karsten Matthies , George Stone , Florian Theil

Stationary distributions of complex Langevin equations are shown to be the complexified path integral solutions of the Schwinger-Dyson equations of the associated quantum field theory. Specific examples in zero dimensions and on a lattice…

High Energy Physics - Theory · Physics 2009-01-26 Gerald Guralnik , Cengiz Pehlevan

We resolve a long standing question regarding the suitable effective diffusion coefficient of the spherically-symmetric transport equation, which is valid at long times. To that end, we generalize a transport solution in three dimensions…

Statistical Mechanics · Physics 2024-02-01 Shay I. Heizler , Menahem Krief , Michael Assaf

Quantum-confined semiconductor structures are the cornerstone of modern-day electronics. Spatial confinement in these structures leads to formation of discrete low-dimensional subbands. At room temperature, carriers transfer among different…

Mesoscale and Nanoscale Physics · Physics 2009-08-14 I. Knezevic , E. B. Ramayya , D. Vasileska , S. M. Goodnick

We generalize the two-channel (Edwards) fermion-boson model describing quantum transport in a background medium to the more realistic case of dispersive bosons. Using the variational exact diagonalization technique, we numerically solve the…

Quantum Gases · Physics 2024-04-11 Monodeep Chakraborty , Holger Fehske

Partial transport barriers in the chaotic sea of Hamiltonian systems influence classical transport, as they allow for a small flux between chaotic phase-space regions only. We establish for higher-dimensional systems that quantum transport…

Chaotic Dynamics · Physics 2023-08-03 Jonas Stöber , Arnd Bäcker , Roland Ketzmerick

Scaling arguments imply that quantum critical points exhibit universal non-linear responses to external probes. We investigate the origins of such non-linearities in transport, which is especially problematic since the system is necessarily…

Superconductivity · Physics 2007-05-23 A. G. Green , S. L. Sondhi

We develop a formalism to carry out coarse-grainings in quantum field theoretical systems by using a time-dependent projection operator in the Heisenberg picture. A systematic perturbative expansion with respect to the interaction part of…

High Energy Physics - Theory · Physics 2008-11-26 Tomoi Koide

In this paper the Boltzmann equation describing the carrier transport in a semiconductor is considered. A modified Chapman-Enskog method is used, in order to find approximate solutions in the weakly non-homogeneous case. These solutions…

Statistical Mechanics · Physics 2007-05-23 S. F. Liotta , A. Majorana

The collisionless Boltzmann equation, also called free-streaming, is a convenient approximation. It is rather simple to implement numerically, and and it is effective at reducing the irregularities of rough initial conditions. It can be…

High Energy Physics - Phenomenology · Physics 2023-04-04 Leonardo Tinti