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kodama said:what kind of dark matter is left?
Fuzzy dark matter.
W. Hu, R. Barkana, and A. Gruzinov, “Cold and fuzzy dark matter,” Phys. Rev. Lett. 85, 1158–1161 (2000), https://arxiv.org/abs/astro-ph/0003365
One of the big conundrums is that the assumption of dark matter works extremely well on large scales for explaining the structure of the cosmos, but seems to fail to work on the scale of galaxies. One interesting idea how to fix this (without giving up on the established theory of gravity as MOND does) is to assume that dark matter consists of massive but extremely light particles, whose de Broglie wavelength is of the order of thousands of parsecs. This has the consequence that at around the scale of that wavelength the behaviour of this dark matter changes.
Now Edward Witten et al. have argued in more detail that this works really well, and consistent with existing null results on direct detection:
Lam Hui, Jeremiah P. Ostriker, Scott Tremaine, Edward Witten, "On the hypothesis that cosmological dark matter is composed of ultra-light bosons" https://arxiv.org/abs/1610.08297