Heavy neutrino reintroduced in study

A new theoretical model suggests that a heavy neutrino, previously excluded from most studies of neutrino mass, might have played a role in the early universe. This neutrino could explain why matter survived antimatter after the Big Bang, a mystery that has puzzled scientists for decades.

Matter-antimatter imbalance explained

Matter and antimatter annihilate upon contact, and if the Big Bang had created equal amounts, the universe would be empty. However, the universe is filled with atoms, indicating that matter prevailed over antimatter, and this new model proposes a possible reason for that imbalance.

Switching mechanism connects neutrino masses

The researchers introduced a mechanism called "switching" that links the tiny mass of ordinary neutrinos to that of much heavier partners. According to this mechanism, the heavier the partner, the lighter the neutrino becomes, offering a way to explain the mass differences observed in experiments.

Longevity of the heavy neutrino

This heavy neutrino interacts very weakly with surrounding matter, giving it an exceptionally long lifespan. Its longevity could have altered the history of cosmic expansion, as it behaves differently from other particles in the early universe, influencing how the universe expanded and evolved over time.