Nemanja Kaloper

In the first moments after the Big Bang, the Universe expanded at an enormous speed. If the expansion briefly paused, it generated powerful gravitational waves. Future detectors on Earth will be able to catch them, opening a window into an era hidden from any telescopes.

The cosmic microwave background not only brings a map of the early universe but also a subtle twist in polarization—just a few thousandths of a radian. For a long time, it was attributed to ultralight axions, but they clash with experiments. A new explanation is more elegant: the rotation arises whe