Recently it has been claimed that ordinary perturbation theory (OPT) gives incorrect weak coupling expansions for lattice O( N) non-linear sigma models in the infinite volume limit, and in particular that the two-dimensional non-abelian models are not asymptotically free, contrary to previous ...
Berenyia, Region of validity of perturbation theory for dielectrics and finite conductors, Waves Random Complex Media 5 (1995), pp. 305-327.Region of validity of perturbation theory for dielectrics and finite conductors. M.-J. Kim,H.M. Berenyi,R.E. Burge,S. Tajbakhsh. Waves in Random ...
We present a study of the region of validity of perturbation theory applied to rough surface scattering. We solve numerically the case of a periodic surface or grating varying in one dimension. For a statistical ensemble of gratings with a sufficiently long period one may obtain a good ...
The accuracy of the first‐ and second‐order perturbation theory approximations for randomly rough, pressure‐release surfaces has been examined through comparison with exact numerical results based on solving an integral equation. A Gaussian roughness spectrum was chosen for the surfaces, and a Monte...
Validity of many-body approximation methods for a solvable model:(i). exact solutions and perturbation theory. Nucl. Phys. 62, 188-198 (1965).Lipkin H J, Meshkov N and Glick A J, Validity of many-body approximation methods for a solvable model: (I). Exact solutions and perturbation ...
Theory and experiment of nanostructure self-organization in irradiated materials Under such conditions, the numerical analysis of the complete dynamical model remains the only way to test the validity of the weakly nonlinear analysis ... NM Ghoniem,D Walgraef,SJ Zinkle - Journal of Computer-Aided ...
The time-dependent fluorescence of a chromophore can be calculated from either nonequilibrium simulations, or, as long as linear response theory holds true, from equilibrium solvent fluctuations in the ground or excited state if the perturbation inflicted by the chromophore is small. The assumption of...
Applicability of multireference many-body perturbation theory to the Ne2 The ground state as well as some low-lying excited states of the Ne2+ molecule are calculated by means of the third-order multirefere... Jozef,Mášik,Ján,... - 《International Journal of Quantum Chemistry》 被引量:...
Application of a "charge-averaged" second order multireference perturbation theory strategy to the study of a model Mixed-Valence compound A new proposed second order Multireference Perturbation Theory (MRPT) approach (termed NEVPT2(av)), based upon the use of state-averaged canonical molecula......
The idea of treating phonon transport as equivalent to transport through a gas of particles is termed the phonon gas model (PGM), and it has been used almost ubiquitously to try and understand heat conduction in all solids. However, most of the modes in disordered materials do not propagate ...