最初の試みはニュートン力学が不完全だと仮定した。
Modified Newtonian Dynamics MOND とよぶが
これはうまくいかなかったとされる。
最新の仮説はErk Verlinde のエントロピー力が暗黒物質にかわるものだ。
一部転載する：
Discussing Gravity with Erik Verlinde
We have just returned from a talk by the Bethe colloquium. Erik Verlinde from the university of Amsterdam spoke about “Dark Matter, Dark Energy and the Emergence of Gravity ”.
Verlinde is a dutch theoretical physicist working on string theory and gravity. He became very famous for his theory of entropic gravity and was awarded theSpinoza Prize for his work.
In his talk, he showed that his approach can not only reproduce the MONDian behavior of the different kinds of galaxies. He even gave an explanation on why the centers of galaxy clusters deviate from the baryonic Tully-Fisher relation by a factor of four. The reason, he says, lies in the distribution of matter. Very roughly, galaxies can be approximated by a point mass if we look at their outskirts only. In galaxy clusters, however, the matter is more evenly distributed. Assuming a spatially constant matter density, he can even motivate the amount of the deviation