Eternal return (German: Ewige wiederkunft; also known as eternal recurrence) is a concept that the universe and all existence and energy has been recurring, and will continue to recur, in a self-similar form an infinite number of times across infinite time or space.

Is it possible that the universe repeats itself?

Yes! All you need is an infinite universe, an eternal universe or an eternally cyclical universe. No matter how unlikely something is, such as the probability that this exact world and moment will be copied somewhere, then in one of these infinities it will repeat itself, an infinite number of times.

How long will it take for the universe to repeat itself?

The universe will cease to exist around the same time our sun is slated to die, according to new predictions based on the multiverse theory. Our universe has existed for nearly 14 billion years, and as far as most people are concerned, the universe should continue to exist for billions of years more.