Friday, March 21, 2014

More Gravitational Wave Reverberations

Someone said that the greatest tragedy in science is the slaughter of beautiful theories by ugly facts. Beautiful or not, the BICEP2 results are apparently creating some theoretical carnage. Andrei Linde's chaotic inflation, with its multiversal implications, looks pretty good. Some other stuff - not so much.

...authors wrote that the measurements made by Kovac's team using the BICEP2 telescope at the South Pole all but ruled out a class of models that attempted to explain both inflation and another cosmic mystery — the nature of dark matter — based on a hypothetical elementary particle called the axion. The researchers did not rule out all axion models, however, only that “this particular class of axions make up only a tiny fraction of the dark matter”, says Marsh.

Cosmologist Marc Kamionkowski of Johns Hopkins University in Baltimore, Maryland, agrees that some axion models no longer work, “because they require inflation to operate at a lower energy scale than the one indicated by BICEP2”.

Kamionkowski says that the BICEP2 discovery would also rule out a plethora of other theories in one fell swoop, including several other ideas on the properties of the energy field that drove inflation. “The family of acceptable models has been collapsed tremendously,” he says.