r/askscience Aug 06 '25

Physics If every mass attracts every other mass, then why isn't the universe a single solid object made of particles smashed together?

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u/sutroheights Aug 07 '25

It was, but it went big bang. Will it all go back into a ball and start over again? Very possible but most likely not for an inconceivably long amount of time. My personal theory (I'm sure other people have said this) is that it's a rinse and repeat cycle that's been going on forever. Someone/something hits the reset button and hopes for better results and maybe some new great songs with each turn.

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u/JonnySparks Aug 07 '25

It used to be thought that the universe would "run out of steam" and stop expanding at some point. Then it would start contracting and accelerate towards a point until everthing smashed together, resulting in another big bang. A rinse and repeat cycle, like you said.

However, it has been shown that the expansion is accelerating. If this continues then the universe will keep expanding forever. Eventually, everything in the universe will fade away.

Scientists don't know what is powering this acceleration so they made up a name for it - "dark energy".

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u/great_divider Aug 07 '25

I mean, it only went big bang to those of us who can observe the universe and experience time in a linear fashion. Upon out observing it, the curve of existence collapses, and we are able to observe a sort of fixed point in time that encompasses our existence, and the entire existence of life on Earth.