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Soliton-pair Propagation under Thermal Bath Effect

N. Boutabba, H. Eleuch (2012)

Mathematical Modelling of Natural Phenomena

We consider two atomic transitions excited by two variable laser fields in a three-level system. We study the soliton-pair propagation out of resonance and under thermal bath effect. We present general analytical implicit expression of the soliton-pair shape. Furthermore, we show that when the coupling to the environment exceeds a critical value, the soliton-pair propagation through three-level atomic system will be prohibited.

Solitons and Gibbs Measures for Nonlinear Schrödinger Equations

K. Kirkpatrick (2012)

Mathematical Modelling of Natural Phenomena

We review some recent results concerning Gibbs measures for nonlinear Schrödinger equations (NLS), with implications for the theory of the NLS, including stability and typicality of solitary wave structures. In particular, we discuss the Gibbs measures of the discrete NLS in three dimensions, where there is a striking phase transition to soliton-like behavior.

Solutions of the Dirac-Fock equations without projector

Éric Paturel (2000)

Journées équations aux dérivées partielles

In this paper we prove the existence of infinitely many solutions of the Dirac-Fock equations with N electrons turning around a nucleus of atomic charge Z , satisfying N < Z + 1 and α max ( Z , N ) < 2 / ( 2 / π + π / 2 ) , where α is the fundamental constant of the electromagnetic interaction (approximately 1/137). This work is an improvement of an article of Esteban-Séré, where the same result was proved under more restrictive assumptions on N .

Sparse grids for the Schrödinger equation

Michael Griebel, Jan Hamaekers (2007)

ESAIM: Mathematical Modelling and Numerical Analysis

We present a sparse grid/hyperbolic cross discretization for many-particle problems. It involves the tensor product of a one-particle multilevel basis. Subsequent truncation of the associated series expansion then results in a sparse grid discretization. Here, depending on the norms involved, different variants of sparse grid techniques for many-particle spaces can be derived that, in the best case, result in complexities and error estimates which are independent of the number of particles. Furthermore...

Strong field, noncommutative QED.

Ilderton, Anton, Lundin, Joakim, Marklund, Mattias (2010)

SIGMA. Symmetry, Integrability and Geometry: Methods and Applications [electronic only]

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