2014/06/25 by Hsi-Yu Schive, Tzihong Chiueh, Tom Broadhurst · 6 citations
Physics and Astronomy · #astro-ph.GA #astro-ph.CO
paper · pdf · doi:10.1038/nphys2996
14 pages, 8 figures. Pre-submission version. Final version has appeared in Nature Physics (http://dx.doi.org/10.1038/nphys2996)
arxiv created 2014/06/25 · arxiv updated 2014/06/26
The conventional cold, particle interpretation of dark matter (CDM) still lacks laboratory support and struggles with the basic properties of common dwarf galaxies, which have surprisingly uniform central masses and shallow density profiles. In contrast, galaxies predicted by CDM extend to much lower masses, with steeper, singular profiles. This tension motivates cold, wavelike dark matter (ψDM) composed of a non-relativistic Bose-Einstein condensate, so the uncertainty principle counters gravity below a Jeans scale. Here we achieve the first cosmological simulations of this quantum state at unprecedentedly high resolution capable of resolving dwarf galaxies, with only one free parameter, \bfmB, the boson mass. We demonstrate the large scale structure of this ψDM simulation is indistinguishable from CDM, as desired, but differs radically inside galaxies. Connected filaments and collapsed haloes form a large interference network, with gravitationally self-bound solitonic cores inside every galaxy surrounded by extended haloes of fluctuating density granules. These results allow us to determine \bfmB=(8.1+1.6-1.7)× 10-23~eV using stellar phase-space distributions in dwarf spheroidal galaxies. Denser, more massive solitons are predicted for Milky Way sized galaxies, providing a substantial seed to help explain early spheroid formation. Suppression of small structures means the onset of galaxy formation for ψDM is substantially delayed relative to CDM, appearing at \bfz\lesssim 13 in our simulations.