...Dr Heymans conceded that we still need to find out the nature of the
dark matter particle, as well as discover more about the even more
mysterious dark energy, which serves to drive the Universe's expansion
even as dark matter works to draw things together.
"I'll be very honest with you, we don't know what the dark
matter particle is, we don't know what this dark energy is coming from,"
she said.
"It's very widely believed that our final understanding of
the 'dark universe' is going to have to invoke some new physics,
something that will forever change our view of the Universe...
Dark energy and dark matter mysteries
* Gravity acting across vast distances does not seem to explain what astronomers see
* Galaxies, for example, should fly apart; some other mass must be there holding them together
* Astrophysicists have thus postulated "dark matter" - invisible to us but clearly acting on galactic scales
* At the greatest distances, the Universe's expansion is accelerating
* Thus we have also "dark energy" which acts to drive the expansion, in opposition to gravity
* The current theory holds that 73% of the Universe is dark energy, 23% is dark matter, and just 4% the kind of matter we know well
Full article: http://www.bbc.co.uk/news/science-environment-16477774
