A simulation of early galaxy formation under three dark matter scenarios. cold dark matter: early galaxies would 1st form in bright halos (far left). If warm, galaxies would form 1st in long, tail-like filaments (center). Fuzzy one would produce similar filaments, though striated (far right).

http://bit.ly/31UDRYU via /r/spaceporn http://bit.ly/2LM3chO