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arXiv · hep-ph/0703175

Quantum Boltzmann Equations and Leptogenesis

Andrea De Simone·Antonio Riotto
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Abstract

The closed time-path formalism is a powerful Green's function formulation to describe non-equilibrium phenomena in field theory and it leads to a complete non-equilibrium quantum kinetic theory. We make use of this formalism to write down the set of quantum Boltzmann equations relevant for leptogenesis. They manifest memory effects and off-shell corrections. In particular, memory effects lead to a time-dependent CP asymmetry whose value at a given instant of time depends upon the previous history of the system. This result is particularly relevant when the asymmetry is generated by the decays of nearly mass-degenerate heavy states, as in resonant or soft leptogenesis.

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Andrea De Simone, Antonio Riotto. 2007-10-02. Quantum Boltzmann Equations and Leptogenesis. https://doi.org/10.1088/1475-7516%2F2007%2F08%2F002

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