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Exact Conservation Laws of the Gradient Expanded Kadanoff-Baym Equations

J. Knoll·Yu. B. Ivanov·D. N. Voskresensky
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Abstract

It is shown that the Kadanoff-Baym equations at consistent first-order gradient approximation reveal exact rather than approximate conservation laws related to global symmetries of the system. The conserved currents and energy-momentum tensor coincide with corresponding Noether quantities in the local approximation. These exact conservations are valid, provided a Phi-derivable approximation is used to describe the system, and possible memory effects in the collision term are also consistently evaluated up to first-order gradients.

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J. Knoll, Yu. B. Ivanov, D. N. Voskresensky. 2001-02-19. Exact Conservation Laws of the Gradient Expanded Kadanoff-Baym Equations. https://doi.org/10.1006/aphy.2001.6185

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