In the first moments after the Big Bang, space boiled. A superheated substance permeating the world gave rise to giant bubbles of a new phase – much like a liquid produces vapor. Collisions of these bubbles accelerated particles to energies unimaginable in Earthly accelerators.
In this seething cauldron, super-heavy neutrinos were born – massive relatives of particles predicted by Wolfgang Pauli. The stable ones might be dark matter, the invisible skeleton of galaxies discovered by Vera Rubin. As they decay, they create an excess of matter over antimatter – the reason stars and planets exist.
The real surprise is the gravitational echo: not brief bursts but a continuous low-frequency hum of gravitational waves that permeates the cosmos. It can be picked up by future detectors like LISA. This scenario, based on an extension of the Standard Model, for the first time links dark matter and this hum through a single mechanism – bubbles that burst at the dawn of time.
The temperature of this cosmic 'boiling' was a billion times higher than that at the Sun's core.
This low hum that fills the cosmos may be the first whisper of an invisible world, one we'll soon decipher.