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Agnostics usually say you can't possibly know if there is a God or not. Atheists believe there can't be a God.


Not 100% correct. We don't believe there can't be a God. We just don't believe in God.

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No, what I know is that by the nature of time, time could not have existed forever. There has to be a starting point. Time cannot be an actual infinite, it can only be a potential infinite.


This is your personal opinion, but most mathematicians and physicists wouldn't agree with you. No one has ever proven or found an argument why time should need a starting point.

The same goes for the universe. Our own universe certainly had a starting point, but something else likely existed before. It is possible, but unlikely that the universe came from nothing. Today, physics can only speculate what that "something" was, like an 11-dimensional eternal space with colliding membranes as string theory suggests. But I'm sure in the next decades we'll learn more about what was before the universe.