We present an ab initio quantum theory of the finite-temperature magnetism of iron and nickel. A recently developed technique which combines dynamical mean-field theory with realistic electronic structure methods successfully describes the many-body features of the one electron spectra and the observed magnetic moments below and above the Curie temperature.

in this paper, thermal effect of plasma arc welding is investigated, and temperature field of ferrite stainless steel is acquired. thermal effect of plasma arc and subsequently the generated temperature field in the work piece is the key for analysis and optimization of this welding process, which is the main goal of this paper. finite element simulation of welding process by simplec method and...

Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential. The effective widths(damping rates) are introduced to regulate the pinch singularities. The finite chemical potential, which enhances the contributions to the shear viscosity from the electron...

STATISTICAL QUANTIJM CHROMODYNAMICS..................................................................................... 247 The Gauge Field Theory of Strong Interactions .. ............................ ..................................... 247 The Physical Basis for Deconjinement ...................................................................................... 248 Lattice QCD at Finite Te...

At high temperature the infrared modes of a weakly coupled quantum field theory can be treated nonperturbatively in real time using the classical field approximation. We use this to introduce a nonperturbative approach to the calculation of finite-temperature spectral functions, employing the classical KMS condition in real time. The method is illustrated for the one-particle spectral function ...

We develop a nonperturbative technique in field theory to study properties of infinite nuclear matter at zero temperature as well as at finite temperatures. Here we dress the nuclear matter with off-mass shell pions. The techniques of thermofield dynamics are used for finite temperature calculations. Equation of state is derived from the dynamics of the interacting system in a self consistent m...

Vacuum effects in (2+1)-dimensional quantum electrodynamics (QED) with the topological Chern-Simons term are considered. The photon polarization operator is studied and the decay rate for the electron-positron photoproduction γ → e+ e− is presented as a function of the photon energy and external field strength. The radiatively induced electron mass shift in an external magnetic field is investi...

We study the phase structure of a 4D complex scalar field theory with a potential V (Φ) = | Λ 3 Φ −ΛΦ | 2 at zero and at finite temperature. The model is analyzed by mean-field and Monte Carlo methods. At zero temperature the theory falls in the universality class of the 4D Ising model when varying Λ. The situation is less clear-cut for variations w.r.t. Λ at large temperatures and variations w...

Vacuum effects in (2+1)-dimensional quantum electrodynamics (QED) with the topological Chern-Simons term are considered. The photon polarization operator is studied and the decay rate for the electron-positron photoproduction γ → e+ e− is presented as a function of the photon energy and external field strength. The radiatively induced electron mass shift in an external magnetic field is investi...

We study the conditions under which an overdamped regime can be attained in the dynamic evolution of a quantum field configuration. Using a ∗E-mail: [email protected] †E-mail: [email protected]. NSF Presidential Faculty Fellow. ‡E-mail: [email protected] 1 real-time formulation of finite temperature field theory, we compute the effective evolution equation of a ...