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Comment by blake1 | Hacker News Reader

This is about gravitomagnetism. It would be beautiful if someone who studies electromagnetism in a turbulent plasma explain dark matter away. But these efforts always flounder on the bullet cluster results. I’m not going to get excited until I can see how those data are disposed of.

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There is absolutely no need for gravitomagnetism to explain the bullet cluster.

If it accounts for rotation curves, or even just a substantial fraction of rotation curves, that's a box checked: GR and (those) galaxies' rotation turn out consistent after all.

Then it will be DM's problem to explain why DM shows up only where a fudge is needed.

My expectation is that the universe will not cease to mystify for a long time. We can live with the Bullet Cluster losing its (maybe too-) convenient explanation.

Also: gravitomagnetism is taught in pretty much every textbook on GR. It'd be a bit surprising if the people who wrote those textbooks (e.g. Steve Weinberg) didn't notice that elementary topics in their own textbooks could solve major problems in their fields.

I don't think people working with GR did ignore it like the author suggest, the paper seems to cite older attempts to reconcile the phenomena using more simplified models. Also another comment further down seeming to observe the same thing: https://news.ycombinator.com/item?id=26442664

It seems that the phenomenon is already part of cosmological simulations.

https://sciencenode.org/feature/toward-a-realistic-cosmic-ev...

(Note: frame-dragging is another term for gravitomagnetism)

Anthony Peratt already figured this stuff out years ago with Plasma Cosmology.

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