Nemanja Kaloper

Right after its birth, the Universe wasn't just expanding: it was inflating at an unimaginable pace. This stage, called inflation, was proposed by Alan Guth. New models compare the process to inflating a balloon with quick, jerky pumps.

The universe is not emptiness, but a vast crystalline sphere, threaded with invisible boundaries — domain walls frozen after phase transitions.

A pebble drops into a pond, and ripples spread across the water. But one wave suddenly doesn't spread out: it clings to an invisible fold on the surface and runs only along it.

Light from the very beginning of the cosmos has been traveling toward us for 13.8 billion years. During that time, its polarization, the direction of its oscillations, might have been twisted, like a compass needle that someone quietly nudged. Physicists call this phenomenon cosmic birefringence.