Close to a breakthrough? (Image: CERN)
Read more: “Instant Expert: Dark matter“
Dark matter is at a crossroads. Few problems have received more attention from physicists and astronomers in recent years than trying to discover what it is and how it works. So far, there are few concrete facts, just educated guesses.
That could soon change. Any of the types of dark matter searches – direct detection in deep mines, indirect detection with space telescopes, or the Large Hadron Collider – could be near a breakthrough. Are CoGeNT and DAMA/LIBRA seeing dark matter? Is dark matter producing the gamma rays that the Fermi space telescope has observed coming from the centre of our galaxy? There is as yet no consensus on these questions, but time and more data should provide answers.
If dark matter is in fact made up of “weakly interactive massive particles” (WIMPs), such as particles similar to those predicted by supersymmetry, success could be just around the corner. On the other hand, if no such signals appear in the coming decade, physicists are going to have to throw out much of what they think they know about dark matter and dream up new possibilities. Perhaps dark matter is entirely inert, and does not interact at all with normal matter. If so, it will never be detectable by any of the experiments physicists have been designing – a dark matter hunter’s worst nightmare.
If I were to make a bet, I would put my money on the first unambiguous evidence for particle dark matter appearing within the next few years. Once those detections start taking place, …
