An old friend just sent me this article which discusses new results from gas-rich galaxies in favour of Modified Newtonian Dynamics theory (MOND).BBC News - Dark matter theory challenged by gassy galaxies result
This coincides nicely with this article I was reading about how the LHC has so far failed to find supersymmetric particles ("sparticles") at the electroweak scale. These particles were thought to be the most likely candidates for dark matter.
Could this be the end for dark matter theory? Well, no. Certainly not at this stage. The author of the gassy galaxies study, Stacy McGraugh, admits that MOND still produces poor results on the scale of galactic clusters. And the LHC results are still a long way from ruling out supersymmetry. It could be that the particles have not been seen because their masses are beyond the range the ATLAS experiment has been looking at - although SUSY models do begin to get complicated if the sparticles involved are very heavy.
It will be interesting to see what results emerge from the LHC in 2011. The collider began to reawaken from its winter shutdown on Feb 19th, when the particle beams started circulating again. The number of collisions is to be stepped up this year, with 100 times more data expected to be collected in 2011 than in 2010.