Informal Pizza Seminar

Baryogenesis below the TeV scale

Federico Urban

Ferrara University & INFN Ferrara

I will discuss the possibility of generating the cosmological baryon asymmetry at scales below the Electroweak phase transition in Braneworld-gravity models. The idea is that since higher dimensional gravity usually allows to set the gravity scale down to a few TeV, also the highest temperature reached by the universe after inflation cannot be higher than that, thus precluding the standard mechanisms for baryogenesis at high energies. Furthermore, if the reheating temperature is lower than the Electroweak scale, one also cannot rely on sphalerons for generating the asymmetry. The possibly only way to explain the observed lack of antimatter then is to use the inflaton itself as source for baryon number violation. A model in this direction will be discussed