Debasish Borah

The universe sometimes resembles a pot of boiling water. With enough heat, liquid turns to vapor: that's a phase transition. Something similar could have happened in the early universe: a field filling space suddenly changed its state, like water becoming gas.

In the first moments after the Big Bang, matter and antimatter were almost perfectly balanced. But something tipped the scales — otherwise everything would have annihilated into radiation, leaving the universe empty. One candidate for the role of "tipper" is the ultraheavy right-handed neutrino.

In an underground laboratory beneath Sanford Mountain in South Dakota, a tank holding ten tons of liquid xenon waits for a dark matter particle to fly through it. Over 60 days of observation, the LZ detector registered a single nuclear recoil with an energy of 248 keV.