Astronomers have peered back to the dawn of the cosmos to observe time ticking five times more slowly in the early universe than it does now — finally proving a prediction that Albert Einstein made more than a century ago.
Researchers spotted the extreme slow-motion effect in data taken from bright cosmic beacons known as quasars dating to when the universe was just 1 billion years old — less than one-tenth its current age. The researchers published their findings July 3 in the journal Nature Astronomy.
