Physicists may have found an explanation for one of the universe's key mysteries: a hypothetical heavy "right-handed" neutrino could have briefly become the dominant form of energy in the universe, thereby determining matter's victory over antimatter after the Big Bang, infohub.kz reports.
The study was authored by Rishav Roshan of the University of Southampton in the UK and Sudipta Shaw of the Indian Institute of Technology Kanpur. Their research, published in the prestigious journal "Physical Review Letters," examines the role of a hypothetical heavy "right-handed" particle in the early stages of cosmic evolution.
The Standard Model of particle physics assumes that neutrinos have no mass, but quantum oscillations indicate otherwise. The popular seesaw mechanism explains the tiny mass of ordinary left-handed neutrinos through their interaction with hypothetical heavy right-handed counterparts. Theorists typically consider three such neutrinos, but the third is often ignored because of its extreme mass and weak couplings.
Calculations showed that a particle roughly 100 trillion times more massive than a proton could have briefly concentrated more energy within itself than all other matter combined. As the universe cooled and slowed, its energy share rose rapidly, temporarily accelerating cosmic expansion. This slowed the separation of lepton flavors and allowed a lighter partner to generate an excess of leptons. Ultimately, the process produced the observed predominance of matter over antimatter and prevented their complete mutual annihilation.
The LISA gravitational-wave observatories and SKAO radio telescopes will help test the theory.