Related papers: Backreaction Effects on Nonequilibrium Spectral Fu…
Using the Bethe ansatz analysis as was reformulated by Edwards, we calculate the spectral properties of a particle interacting with a bath of fermions in one dimension for the case of equal particle-fermion masses. These are directly…
In these lectures we introduce the functional renormalization group out of equilibrium. While in thermal equilibrium typically a Euclidean formulation is adequate, nonequilibrium properties require real-time descriptions. For quantum…
Recently, an interesting work, which reformulates the tunneling framework to directly produce the Hawking emission spectrum and entropy spectroscopy in the tunneling picture, has been received a broad attention. However, during the emission…
In this work we will show how the back-reaction can be treated as a quantum correction. The novel semi-classical approach presented here consists in the introduction of adequate quantum corrections into the r-t sector of the black hole…
In this paper, we extend the method of Kadanoff-Baym equations for open quantum systems to arbitrary kinds of systems and heat baths, either fermionic or bosonic. This includes three spacial dimensions and different potentials for the…
Shell effects reflects irregularities of physical quantities caused by a discrete energy spectrum. The theory of the shell effects by Kirzhnits and Shpatakovskaya is valid only at relatively low densities providing for oscillations of…
We calculate the energy density and pressure of a scalar field after its decoupling from a thermal bath in the spatially flat Friedman-Lema\^itre-Robertson-Walker space-time, within the framework of quantum statistical mechanics. By using…
We use a functional approach to evaluate the Casimir free energy for a self-interacting scalar field in $d+1$ dimensions, satisfying Dirichlet boundary conditions on two parallel planes. When the interaction is turned off, exact results for…
We use cosmological perturbation theory to study the backreaction effects of a self-consistent and well-defined cosmological averaging on the dynamics and the evolution of the Universe. Working with a perturbed…
Radiation reaction (but, more generally, fluctuations and dissipation) occurs when a system interacts with a heat bath, a particular case being the interaction of an electron with the radiation field. We have developed a general theory for…
Classical response functions have shown considerable promise in computational 2D IR modeling; however, a simple diagrammatic description, analogous to that for open quantum systems, has been lacking. While a promising diagrammatic approach…
Relaxation process of a coherent scalar field oscillation in the thermal bath is investigated using nonequilibrium quantum field theory. The Langevin-type equation of motion is obtained which has a memory term and both additive and…
We examine two point correlation functions involving the trace of the energy momentum tensor in five dimensional gravity dual theories supported by one or more scalar fields. A prescription for determining bulk channel spectral functions is…
We discuss the ringdown behavior of the nonequilibrium Green's function in a strongly coupled theory with the holographic dual with a focus on quasinormal-mode equilibration. We study the time resolved spectral function for a probe scalar…
The effective evolution of an inhomogeneous universe model in any theory of gravitation may be described in terms of spatially averaged variables. In Einstein's theory, restricting attention to scalar variables, this evolution can be…
The effect of particle creation by nonstationary external fields is considered as a radiation effect in the expectation-value spacetime. The energy of created massless particles is calculated as the vacuum contribution in the…
Deviations from kinetic equilibrium of massive particles caused by the universe expansion are calculated analytically in the Boltzmann approximation. For the case of an energy independent amplitude of elastic scattering, an exact partial…
We present a quantum kinetic approach for the time-resolved description of many-body effects in photoionization processes in atoms. The method is based on the non-equilibrium Green functions formalism and solves the Keldysh/Kadanoff-Baym…
It is possible that there may exist long-range forces in addition to gravity. In this paper we construct a simple model for such a force based on exchange of a massless scalar field and analyze its effect on the evolution of a homogeneous…
In a recent work, we had constructed a model consisting of two fields---a canonical scalar field and a non-canonical ghost field---that had sourced a symmetric matter bounce scenario. The model had involved only one parameter, viz. the…