News today on the dark matter front:

“Astronomers have discovered a chaotic scene unlike any witnessed before in a cosmic “train wreck” between giant galaxy clusters. NASA`s Chandra X-ray Observatory and optical telescopes revealed a dark matter core that was mostly devoid of galaxies, which may pose problems for current theories of dark matter behavior.”

The article goes on to state that specific issue seems to be that gravitational force of the dark matter should have been strong enough to keep the missing mass from going missing. Either a fortuitous slingshot effect cleared out the missing mass, or there’s something very interesting about dark-matter/gravity interactions that we haven’t imagined yet.

But if the latter is true, then it means the whole theory of dark matter may have to be recast in some pretty fundamental ways…

Read the rest here: Dark matter mystery deepens in cosmic ‘train wreck’

(Via Physics Org.)