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arXiv:hep-ph/0101160 · Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields

Model for decoherence of entangled beauty

Reinhold A. Bertlmann, Walter Grimus

Published Jul 16, 2001• 63 citations
arXivHTMLPDF

Abstract

In the context of the entangled ${B}^{0}{B}^{0}$ state produced at the $\ensuremath{\Upsilon}(4S)$ resonance, we consider a modification of the usual quantum-mechanical time evolution with a dissipative term, which contains only one parameter denoted by $\ensuremath{\lambda}$ and respects complete positivity. In this way a decoherence effect is introduced in the time evolution of the two-particle ${B}^{0}{B}^{0}$ state, which becomes stronger with increasing distance between the two particles. While our model of time evolution has decoherence for the two-particle system, we assume that, after the decay of one of the two B mesons, the resulting one-particle state obeys the purely quantum-mechanical time evolution. From the data on dilepton events we derive an upper bound on $\ensuremath{\lambda}.$ We also show how $\ensuremath{\lambda}$ is related to the so-called ``decoherence parameter'' $\ensuremath{\zeta},$ which parametrizes decoherence in neutral flavored meson-antimeson systems.

DOI
10.1103/physrevd.64.056004

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