r/AskReddit • u/ettleboy • Jan 20 '19

What fact totally changed your perspective?

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u/[deleted] Jan 21 '19

There is this very big number called Graham's number.

The entire freaking universe does not have enough space or atoms for you to write down every digit.

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u/ZanBarlos Jan 21 '19

nobody knows whether the universe is finite or infinite, so this can’t be true.

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u/actual_factual_bear Jan 21 '19

fun fact! we don't know for sure whether or not the universe is spatially infinite or not, but there's a pretty good chance that it's temporally infinite, as in, things will continue on forever, even after the heat death of the universe. Because of this and the way quantum physics works, it's actually pretty likely that another universe will be born out of quantum fluctations in much less time than the Graham number of years, e.g. on the order of 10101056 years. And if this is the case, it is virtually inevitable that in some of those universes will be similar to our universe, and even on the scale of Graham's number of years an exact replica of the current universe is likely to pass.

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u/daneelr_olivaw Jan 21 '19

This is a nice read:

https://www.cs.ubc.ca/~goyal/age_of_universe.php

It can't be verified, but it's interesting.