303 research outputs found
Recent progress in Affleck-Dine baryogenesis
In the MSSM, cosmological scalar field condensates formed along flat
directions of the scalar potential (Affleck-Dine condensates) are typically
unstable with respect to formation of Q-balls, a type of non-topological
soliton. I discuss the creation and growth of the quantum seed fluctuations
which catalyse the collapse of the condensate. In D-term inflation models, the
fluctuations of squark fields in the flat directions also give rise to
isocurvature density fluctuations stored in the Affleck-Dine condensate. After
the condensate breaks up, these can be perturbations in the baryon number, or,
in the case where the present neutralino density comes directly from B-ball
decay, perturbations in the number of dark matter neutralinos. The latter case
results in a large enhancement of the isocurvature perturbation, which should
be observable by PLANCK.Comment: 8 pages, 2 figures; invited talk at COSMO9
Flat direction condensate instabilities in the MSSM
Coherently oscillating scalar condensates formed along flat directions of the
MSSM scalar potential are unstable with respect to spatial perturbations if the
potential is flatter than phi^2, resulting in the formation of non-topological
solitons such as Q-balls. Using renormalization group we calculate the
corrections to the phi^2 potential for a range of flat directions and show that
unstable condensates are a generic feature of the MSSM. Exceptions arise for an
experimentally testable range of stop and gluino masses when there are large
admixtures of stops in the flat direction scalar.Comment: 9 pages, 9 encapsulated postscript figure
The Dynamics of Affleck-Dine Condensate Collapse
In the MSSM, cosmological scalar field condensates formed along flat
directions of the scalar potential (Affleck-Dine condensates) are typically
unstable with respect to formation of Q-balls, a type of non-topological
soliton. We consider the dynamical evolution of the Affleck-Dine condensate in
the MSSM. We discuss the creation and linear growth, in F- and D-term inflation
models, of the quantum seed perturbations which in the non-linear regime
catalyse the collapse of the condensate to non-topological soliton lumps. We
study numerically the evolution of the collapsing condensate lumps and show
that the solitons initially formed are not in general Q-balls, but Q-axitons, a
pseudo-breather which can have very different properties from Q-balls of the
same charge. We calculate the energy and charge radiated from a spherically
symmetric condensate lump as it evolves into a Q-axiton. We also discuss the
implications for baryogenesis and dark matter.Comment: 21 pages LaTeX, 11 figure
- …