High Energy Theory Seminar

Solutions of string/M theory with low energy supersymmetry breaking generically have light moduli fields whose masses are of order the supersymmetry breaking scale. These fields -- whose expectation values parametrise the size and shape of the extra dimensions -- tend to dominate the energy density of the early Universe prior to Big Bang Nucleosynthesis. This generically implies that dark matter is NOT produced via a phase of thermal equilibrium, hence it is non-thermal. In general one expects that non-thermal dark matter has several different components which include axions and might include WIMPS, but also include hidden sector particles of various kinds. Most direct and indirect dark matter detection experiments are NOT targeting the parameter space relevant for non-thermal dark matter.