Forgotten particle could answer mystery of why we exist, say physicists…

Two theoretical physicists say a little-studied particle called the decoupled heavy neutrino may hold the key to why the universe contains matter at all, the Daily Mail reports.

The researchers, from the University of Southampton and the Indian Institute of Technology Kanpur, published their paper in Physical Review Letters. They argue the particle may have briefly driven rapid expansion in the early universe, tipping the balance between matter and antimatter.

Theory says the Big Bang should have produced equal amounts of both, which would have annihilated each other. Yet the universe is mostly matter. Co-author Dr Rishav Roshan said: “By affecting the interactions and decays of particles during the early universe, these neutrinos can help favour the production of matter over antimatter.”

The idea remains theoretical, and the particle’s existence has not been proven. Roshan said: “This theory could be tested experimentally through upcoming gravitational wave detectors and particle physics experiments.”