Source of CP Violation for the Baryon Asymmetry of the Universe

Abstract

How to account for the matter predominance of our Universe is a fundamental issue at the core of our existence. One condition is CP violation, but the Standard Model falls short by more than $10^{-10}$. Taking cue from a recent result from the $B$ factories, we find that a fourth quark generation can provide enhancement by a factor of $10^{13}$ or more. This could be the source of CP violation for the baryon asymmetry of the Universe. The main source of enhancement is the large Yukawa couplings of the heavy $t^{\prime }$ and $b^{\prime }$ quarks. With indications for a new, large CP violating phase $\sin 2{\Phi }_{B_s}$ emerging at the Tevatron, our suggestion can be verified or refuted at the LHC in the next few years.

Comments: 4 pages, 1 figure, talk presented at ICHEP2008; minor changes with reference added