Gravitationally speaking, the universe is a noisy place. A hodgepodge of gravitational waves from unknown sources streams unpredictably around space, including possibly from the early universe.

At a sleep research symposium in January 2020, Janna Lendner presented findings that hint at a way to look at people’s brain activity for signs of the boundary between wakefulness and unconsciousness.

It has become extremely common for people to sleep with noise —whether that be white noise, a fan running, rain sounds, or peaceful music. Many people who sleep with noise swear by it, stating that ...