Dark matter is:

Le 02/11/2017 =C3=A0 03:40, Phillip Helbig (undress to reply) a =C3=A9crit=
=C2=A0:
Yes, this is MOND, essentially.

Yes, it is MOND. But I do not think that is a modified gravity what is
behind but just a new force, unrelated to gravity.

Anyway I would like to know what do you think about MOND. Why it hasn't
been accepted by the community at large? What are the problems with it?

Thanks for your patience with me...

:-)

jacob

[[Mod. note -- There are two "aesthetic" objections to MOND which
account for a lot of its low acceptance:
* Ockham's razor suggests "not multiplying hypotheses unneccsarily",
and hypothesizing that there's some matter clustered around galaxies
which is hard to detect with today's telescope technology (i.e.,
dark matter) seems a much lesser extrapolation than hypothesizing
either a modification to gravity (MOND) or a whole new force unrelated
to gravity.
* It's hard to construct a MOND theory which respects what we know
about special relativity: the basic idea of MOND is that you modify
gravity in "weak fields"... but how do you define "weak" in an
observer-independent way? There have been some attempts made
in this direction (like TeVS), but they have other problems.
-- jt]]