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Théorie de la diffusion pour le modèle de Nelson et problème infrarouge

Christian Gérard (2003)

Journées équations aux dérivées partielles

Nous considérons dans cet exposé la théorie de la diffusion pour des modèles de Pauli-Fierz sans masse divergents infrarouge. Nous montrons que les représentations CCR obtenues a partir des champs asymptotiques contiennent des secteurs cohérents décrivant un nombre infini de bosons asymptotiquement libres. Nous formulons quelques conjectures qui conduisent a une notion bien définie de sections efficaces inclusives et non inclusives pour les Hamiltoniens de Pauli-Fierz. Finalement nous donnons une...

Theory and numerical approximations for a nonlinear 1 + 1 Dirac system

Nikolaos Bournaveas, Georgios E. Zouraris (2012)

ESAIM: Mathematical Modelling and Numerical Analysis

We consider a nonlinear Dirac system in one space dimension with periodic boundary conditions. First, we discuss questions on the existence and uniqueness of the solution. Then, we propose an implicit-explicit finite difference method for its approximation, proving optimal order a priori error estimates in various discrete norms and showing results from numerical experiments.

Theory and numerical approximations for a nonlinear 1 + 1 Dirac system

Nikolaos Bournaveas, Georgios E. Zouraris (2012)

ESAIM: Mathematical Modelling and Numerical Analysis

We consider a nonlinear Dirac system in one space dimension with periodic boundary conditions. First, we discuss questions on the existence and uniqueness of the solution. Then, we propose an implicit-explicit finite difference method for its approximation, proving optimal order a priori error estimates in various discrete norms and showing results from numerical experiments.

Time and space complexity of reversible pebbling

Richard Královič (2004)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

This paper investigates one possible model of reversible computations, an important paradigm in the context of quantum computing. Introduced by Bennett, a reversible pebble game is an abstraction of reversible computation that allows to examine the space and time complexity of various classes of problems. We present a technique for proving lower and upper bounds on time and space complexity for several types of graphs. Using this technique we show that the time needed to achieve optimal space for...

Time and space complexity of reversible pebbling

Richard Královič (2010)

RAIRO - Theoretical Informatics and Applications

This paper investigates one possible model of reversible computations, an important paradigm in the context of quantum computing. Introduced by Bennett, a reversible pebble game is an abstraction of reversible computation that allows to examine the space and time complexity of various classes of problems. We present a technique for proving lower and upper bounds on time and space complexity for several types of graphs. Using this technique we show that the time needed to achieve optimal space for...

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