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New research suggests that our universe has no dark matter (phys.org)

submitted 8 months ago by [email protected] to c/[email protected]

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[–] [email protected] 49 points 8 months ago (1 children)

"In standard cosmology, the accelerated expansion of the universe is said to be caused by dark energy but is in fact due to the weakening forces of nature as it expands, not due to dark energy."

Fascinating! I'm looking forward to seeing where this goes. The "tired light" theory they mention doesn't seem to have held up to scrutiny, but maybe there's something else about weakening over time or distance that we haven't observed yet.

[–] MaliciousKebab 3 points 8 months ago (1 children)

How would the gravitational forces weakening accelerate the expansion speed? It would at best "not slow it down", you can't explain the speed increase with this logic. That just sounds wrong. Am I missing something?

[–] [email protected] 0 points 8 months ago* (last edited 8 months ago) (1 children)

Would it be that as gravity weakens, the inertial forces of a spinning galaxy allow it to spread without the gravitational drag that would otherwise slow it down as it expanded?

This is purely my filthy casual’s intuitive take. I’m happy to hear what’s off about it.

[–] MaliciousKebab 1 points 8 months ago

I think you mixed up galaxies moving away from each other, and a galaxy's stars etc. moving in space.

As per Einstein's relativity theory, gravitational force has infinite range. So there will always be some pulling force between galaxies, which means they would eventually slow down and and eventually start moving towards each other. But our observations suggest that they are moving even faster day by day. So there must be some force that is stronger than gravity and it must be somehow pushing objects.

So gravity by itself doesn't explain the speed increase of universe's expantion.