BARYOGENESIS, SPHALERONS, AND THE COGENERATION OF DARK MATTER

Processes involving the electroweak anomaly can erase completely a primordial baryon and lepton asymmetry if B - L = O. This has led to the search for plausible mechanisms for weak-scale baryogenesis, or for the generation of a primordial B - L asymmetry. Here it is emphasized that if another quantum number conserved up to anomalies is present electroweak anomaly processes would not necessarily erase a primordial baryon asymmetry even if B - L = O. Moreover, an asymmetry in the new quantum number that is comparable to the baryon asymmetry is generated concomitantly due to the electroweak anomaly. This asymmetry could be the origin of dark matter.