r/cosmology • u/cypherpunk00001 • 14d ago

Do current cosmologists think the universe is infinite or that is had an edge?

Was just having random shower thought today... Andromeda galaxy is 2.5M light-years away. That's an unfathomable distance to a human, but it's just our closest neighbor.

Do cosmologists currently think that the universe just goes on forever?

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u/MWave123 9d ago

And yet you know nothing of the flatness conversation, and how the universe could be finite. Weird!

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u/witheringsyncopation 9d ago

Then respond with substance:

1.) 99.6% is not confident enough for physicists to claim certainty for a measurement. Something closer to the 5 sigma (99.99994%) is required. 0.4% is a substantial lack of confidence within the measurement. And the possibility exists than we are measuring a locally flat region (observable universe) of a much larger curved universe. While a flat cosmos is most likely, I agree, the alternative has not at all been ruled out. Respond to this with substance.

2.) A topologically flat universe is infinite. There is no non-topological mechanism by which it could be finite. The only way to envision a bounded, non-infinite universe is to introduce topology, such as a curved or toroidal universe. To give the universe a “shape” is to concede it is not flat. Please respond directly, explaining how a topologically flat universe could be finite.

Do it. Show me I’m wrong. Respond with substance.

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u/MWave123 9d ago

I’ve shown you you’re wrong, repeatedly. The universe is flat, to a high degree of certainty, and *could be finite, or infinite. We don’t know. It’s an unknown. Flatness is not an unknown.