The Internet Archive has digitized a microfilm copy of this work. It may be possible to borrow a copy for reading.
The special term he proposes to append to this microscopic equation is nonlinear, conserves the mean value of the energy in time and redistributes the eigenvalues of the density matrix so that they approach ... The author attempts to introduce irreversibility from the start, beginning with the Schrédinger-von Neumann equation for the density matrix. ...
The solution of this equation of motion reveals secular terms that grow in time, the dynamical renormalization group resums these secular terms in real time and leads directly to the quantum kinetic equation ... We derive quantum kinetic equations from a quantum field theory implementing a diagrammatic perturbative expansion improved by a resummation via the dynamical renormalization group. ... Furthermore, we have established a very close relationship between the usual renormalization group and the dynamical renormalization group approach to kinetics. ...doi:10.1103/physrevd.61.065006 fatcat:rqry2zqzbvaffii4jdb5xb3ely
Using a tensor renormalization group method with oblique projectors for an anisotropic tensor network, we confirm that the rescaled spectrum of transfer matrices at nonequilibrium critical points in the ... (1+1)-dimensional directed percolation, a canonical model of nonequilibrium critical phenomena, is scale-invariant and its structure is universal. ... Tensor renormalization group method with oblique projectors.-The use of a TN representation is expanding not only to equilibrium systems but also to nonequilibrium ones. ...arXiv:2008.10807v1 fatcat:ju2l7zjh45cuhckq77lrj6pgt4
The authors argue that the application of the renormal- ization group to partial differential equations has implications for the way in which systems approach thermodynamic equilibrium 82C Time-dependent ... They make use of renormalization group arguments as frequently applied in the context of quantum field theory and critical phenomena in statistical mechanics. ...
Secondly, we apply and extend the renormalization group method to study nonequilibrium dynamics with the goals of constructing a quantum kinetic description that goes beyond usual Boltzmann kinetics and ... This thesis is devoted to studying aspects of real-time nonequilibrium dynamics in quantum field theory by implementing an initial value formulation of quantum field theory. ... group to study nonequilibrium phenomena directly in real time. ...arXiv:hep-ph/0110220v1 fatcat:lu6do3uirnhijdurkg47scdelm
Summary: “We investigate the renormalization group approach to nonequilibrium field theory. ... group and nonequilibrium action in stochastic field theory. ...
Author’s summary: “We outline the position space renormaliza- tion group approach to phase transition and critical phenomena. ... The density matrix describing the time evolution is derived. ...
The MCRG method, previously used only for equilibrium systems, appears to give useful information also for these nonequilibrium systems. ... We present results of direct computer simulations and of Monte Carlo renorrealization group (MCRG) studies of the nonequilibrium steady states of a spin system with competing dynamics and of the voter ... INTRODUCTION Equilibrium statistical mechanics has developed many powerful tools for the study of phase transitions and critical phenomena. There is no comparable theory for nonequilibrium phenomena. ...doi:10.1007/bf01014891 fatcat:2e4hm2ipnjf7deagdna3wkjetm
Within a generalized Gutzwiller approach which includes the description of mixed state density matrices, we characterize the complete phase diagram and the critical behavior at the phase transition approached ... We discuss an open driven-dissipative many-body system, in which the competition of unitary Hamiltonian and dissipative Liouvillian dynamics leads to a nonequilibrium phase transition. ... In the universal vicinity of the critical point, 1/κt may be viewed as an irrelevant coupling in the sense of the renormalization group. ...doi:10.1103/physrevlett.105.015702 pmid:20867464 fatcat:63caf6lcnnc5ll3l3v5ymw7kha
The resulting nonequilibrium Kubo formula for differential conductance makes it possible to propose the new formula of shot noise S_h, and thus to study shot noise in correlated systems at any temperature ... Using the renormalized perturbation theory, we prove that in the leading order of bias voltage S_h equal to noise power at zero temperature conventionally used as shot noise. ... An attempt to obtain an explicit expression of the density matrix had been already made in Refs. 13,14. ...arXiv:0807.4869v1 fatcat:u56ytfd7zfecfkczjwm2k7acb4
Using two recently developed theoretical approaches, the time-dependent numerical renormalization group and an extended ow equation method, we calculate the real-time evolution of a Kondo spin into its ... The steady state magnetization is found to deviate significantly from its thermal equilibrium value. ... In order to verify this semianalytical approach we employ the recently introduced time-dependent numerical renormalization group method (TD NRG) by Anders and Schiller  . ...doi:10.1103/physrevlett.102.196601 pmid:19518982 fatcat:i5nmumdpajarzlmmk5xd7srh6y
to calculations of static and dynamic critical exponents, field theory renormalization group and ¢-expansions. ... In the seven years after the first edition [1975; MR 54 #12096] this theory evolved greatly, especially in the domains of renormalization group approach and critical dynamics. ...
Quantum transport is studied for the nonequilibrium Anderson impurity model at zero temperature employing the multilayer multiconfiguration time-dependent Hartree theory within the second quantization ... To adress both linear and nonlinear conductance in the Kondo regime, two new techniques of the ML-MCTDH-SQR simulation methodology are introduced: (i) the use of correlated initial states, which is achieved ... Acknowledgments This paper is dedicated to Hans-Dieter Meyer on the occasion of his 70th birthday. The ...doi:10.1016/j.chemphys.2018.03.021 fatcat:4j7xr5znabhipk4osbwhqpahqu
It bears full analogy to the density-matrix renormalization group approach to the ground state of isolated systems, and its numerical complexity scales as a power law with the bond dimension. ... We develop a numerical procedure to efficiently model the nonequilibrium steady state of one-dimensional arrays of open quantum systems, based on a matrix-product operator ansatz for the density matrix ... group (DMRG)    and of the equivalent variational approach based on the matrix product state (MPS) ansatz [45, 46] . ...doi:10.1103/physreva.92.022116 fatcat:o7ci5czvzrc5dpymx2s2qrmpzq
Physical Review B
We introduce a real time version of the functional renormalization group which allows to study correlation effects on nonequilibrium transport through quantum dots. ... Moreover, we study decoherence and relaxation phenomena within the ohmic spin-boson model by mapping the latter to the interacting resonant level model. ... We are grateful to D. Schuricht for providing the RTRG data of Figs. 9 and 10 . This work was supported by the DFG via FOR 723 and KA3360-1/1 (C.K.). ...doi:10.1103/physrevb.85.085113 fatcat:3ppollrzhbdvlmx3ymgrs43tyq
« Previous Showing results 1 — 15 out of 2,471 results