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arXiv · hep-th/9711144

On the choice of initial states in nonequilibrium dynamics

Juergen Baacke·Katrin Heitmann·Carsten Patzold
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Abstract

Imposing initial conditions to nonequilibrium systems at some time t_0 leads, in renormalized quantum field theory, to the appearance of singularities in the variable t-t_0 in relevant physical quantities, such as energy density and pressure. The origin of these `initial singularities' can be traced back to the choice of initial state. We construct here, by a Bogoliubov transformation, initial states such that these singularities are eliminated. While the construction is not unique it can be considered a minimal way of taking into account the nonequilibrium evolution of the system prior to t_0.

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Juergen Baacke, Katrin Heitmann, Carsten Patzold. 1997-11-19. On the choice of initial states in nonequilibrium dynamics. https://doi.org/10.1103/physrevd.57.6398

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