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Liouville Decoherence in a Model of Flavour Oscillations in the presence of Dark Energy

Nick Mavromatos·Sarben Sarkar
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Abstract

We study in some detail the master equation, and its solution in a simplified case modelling flavour oscillations of a two-level system, stemming from the Liouville-string approach to quantum space time foam. In this framework we discuss the appearance of diffusion terms and decoherence due to the interaction of low-energy string matter with space-time defects, such as D-particles in the specific model of ``D-particle foam'', as well as dark energy contributions. We pay particular attention to contrasting the decoherent role of a cosmological constant in inducing exponential quantum damping in the evolution of low-energy observables, such as the probability of flavour oscillations, with the situation where the dark energy relaxes to zero for asymptotically large times, in which case such a damping is absent. Our findings may be of interest to (astrophysical) tests of quantum space-time foam models in the not-so-distant future.

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Nick Mavromatos, Sarben Sarkar. 2005-06-28. Liouville Decoherence in a Model of Flavour Oscillations in the presence of Dark Energy. https://doi.org/10.1103/physrevd.72.065016

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