I New paper gravitomagnetism explains dark matter effects

kodama
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Models of galactic rotation curves built of a general relativistic framework could use gravitomagnetism to explain the effects of dark matter
I'm not sure if this paper belongs in GR or astrophysics but

This articleG. O. Ludwig (2021), Galactic Rotation Curve and Dark Matter According to Gravitomagnetism, European Physical Journal C 81:186, DOI 10.1140/epjc/s10052-021-08967-3

there's no need for dark matter,as GR's Gravitomagnetism could explain galaxy rotation effects, similar in spirit to MOND, but using just plain GR.

could GR experts weigh in on this
 
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The basic idea of gravitomagnetic effects is valid; GR does predict them. The question is whether the paper's estimate of their magnitude for a rotating disk-shaped galaxy is correct. I think it will take some time for other researchers to check the work.
 
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PeterDonis said:
The basic idea of gravitomagnetic effects is valid; GR does predict them. The question is whether the paper's estimate of their magnitude for a rotating disk-shaped galaxy is correct. I think it will take some time for other researchers to check the work.

is gravitomagnetic effects always attractive like gravity, and therefore add up?
 
kodama said:
is gravitomagnetic effects always attractive like gravity

No. The effects in general are not as simple as just changing the magnitude of a central force. (That is also true of ordinary magnetism.)
 
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