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DOE OSTI · 21409693

Flavored quantum Boltzmann equations

Cirigliano, Vincenzo·Lee, Christopher·Ramsey-Musolf, Michael J·Tulin, Sean
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Abstract

We derive from first principles, using nonequilibrium field theory, the quantum Boltzmann equations that describe the dynamics of flavor oscillations, collisions, and a time-dependent mass matrix in the early universe. Working to leading nontrivial order in ratios of relevant time scales, we study in detail a toy model for weak-scale baryogenesis: two scalar species that mix through a slowly varying time-dependent and CP-violating mass matrix, and interact with a thermal bath. This model clearly illustrates how the CP asymmetry arises through coherent flavor oscillations in a nontrivial background. We solve the Boltzmann equations numerically for the density matrices, investigating the impact of collisions in various regimes.

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDSASYMMETRYBOLTZMANN EQUATIONCOLLISIONSCOMPOSITE MODELSCP INVARIANCEDENSITY MATRIXDIFFERENTIAL EQUATIONSEQUATIONSFIELD THEORIESFLAVOR MODELINTEGRO-DIFFERENTIAL EQUATIONSINVARIANCE PRINCIPLESKINETIC EQUATIONSMASSMATHEMATICAL MODELSMATHEMATICAL SOLUTIONSMATRICESNUMERICAL SOLUTIONOSCILLATIONSPARTIAL DIFFERENTIAL EQUATIONSPARTICLE MODELSQUARK MODELSIMULATIONTIME DEPENDENCEUNIVERSE

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Cirigliano, Vincenzo, Lee, Christopher, Ramsey-Musolf, Michael J, Tulin, Sean. 2010-05-15. Flavored quantum Boltzmann equations. https://doi.org/10.1103/physrevd.81.103503

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