Cause of the baryon asymmetry of the universe

Determine the exact cause of the observed matter–antimatter (baryon) asymmetry in the universe and ascertain whether mechanisms such as baryogenesis via leptogenesis can account for it.

Background

The universe exhibits a pronounced asymmetry between matter and antimatter, commonly referred to as baryon asymmetry. Although several theoretical frameworks exist, including baryogenesis via leptogenesis with heavy neutral leptons, the definitive origin of this asymmetry is not established.

The paper discusses heavy neutral leptons as a potential ingredient that could generate the required asymmetry through CP-violating decays in the early universe, linking collider searches to a fundamental cosmological question.