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A hierarchy of sum-rules in out of equilibrium QFT

Julien F. J. Salgado
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Abstract

Generalising a result of classical mechanics an infinite set of conserved quantities can be found for the bare equations of motion describing the evolution of a scalar field in out of equilibrium quantum field theory, in the large N approximation, with initial conditions corresponding to a thermal system of the free Hamiltonian. Using these new conserved quantities, sum-rules relating integrals over the mode-functions (momenta) can be derived. More, the corresponding renormalised quantities can also be computed out thus giving information about the evolution of the already known renormalised equations; finally it is also possible to write a renormalised version of the sum-rules.

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Julien F. J. Salgado. 1999-05-14. A hierarchy of sum-rules in out of equilibrium QFT. https://arxiv.org/abs/hep-th/9905106

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