Because of a peculiar effect velocity has on the appearance of the passage of time, our observations make it seem like time ran slower when the Universe was just a baby.
At least, that's how it appears to us, at a light travel time of nearly 13 billion years away. This is called time dilation, and astrophysicist Geraint Lewis of the University of Sydney in Australia and statistician Brendon Brewer of the University of Auckland have seen it in the early Universe for the first time by studying the fluctuations of bright galaxies called quasar galaxies during the Cosmic Dawn.
Because of accelerating expansion of the Universe, they have found, we see those fluctuations unfold at a rate five times slower than if they were occurring nearby.g
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