Baryogenesis and Dark Matter from BB Mesons

We present a new mechanism of Baryogenesis and dark matter production in which both the dark matter relic abundance and the baryon asymmetry arise from neutral $B$ meson oscillations and subsequent decays. This set-up is testable at hadron colliders and $B$-factories. In the early Universe, decays of a long lived particle produce $B$ mesons and anti-mesons out of thermal equilibrium. These mesons/anti-mesons then undergo CP violating oscillations before quickly decaying into visible and dark sector particles. Dark matter will be charged under Baryon number so that the visible sector baryon asymmetry is produced without violating the total baryon number of the Universe. The produced baryon asymmetry will be directly related to the leptonic charge asymmetry in neutral $B$ decays; an experimental observable. Dark matter is stabilized by an unbroken discrete symmetry, and proton decay is simply evaded by kinematics. We will illustrate this mechanism with a model that is unconstrained by di-nucleon decay, does not require a high reheat temperature, and would have unique experimental signals -- a positive leptonic asymmetry in $B$ meson decays, a new decay of $B$ mesons into a baryon and missing energy, and a new decay of $b$-flavored baryons into mesons and missing energy. These three observables are testable at current and upcoming collider experiments, allowing for a distinct probe of this mechanism.Comment: 17 pages, 6 figures. v2: references added, corrected the antinucleon abundance calculation (sec III.C.iii), and included comments on the viability of a measurement of the decay of $b$-flavored baryons into mesons and missing energy at hadron colliders (sec IV.A.iii). v3: matches the published versio

Nonlinear field theories during homogeneous spatial dilation

The effect of a uniform dilation of space on stochastically driven nonlinear field theories is examined. This theoretical question serves as a model problem for examining the properties of nonlinear field theories embedded in expanding Euclidean Friedmann-Lema\^{\i}tre-Robertson-Walker metrics in the context of cosmology, as well as different systems in the disciplines of statistical mechanics and condensed matter physics. Field theories are characterized by the speed at which they propagate correlations within themselves. We show that for linear field theories correlations stop propagating if and only if the speed at which the space dilates is higher than the speed at which correlations propagate. The situation is in general different for nonlinear field theories. In this case correlations might stop propagating even if the velocity at which space dilates is lower than the velocity at which correlations propagate. In particular, these results imply that it is not possible to characterize the dynamics of a nonlinear field theory during homogeneous spatial dilation {\it a priori}. We illustrate our findings with the nonlinear Kardar-Parisi-Zhang equation