From the CalTech website:
Caltech Professor of Physics Jamie Bock and his collaborators announced on March 17, 2014 that they have successfully measured a B-mode polarization signal in the cosmic microwave background (CMB) using the BICEP2 telescope at the South Pole. This signal is an important confirmation of key aspects of the theory of cosmic inflation, about how the universe may have behaved in the first fractions of a second of its existence to create the universe we live in today. Inflation was first proposed in 1980 by Alan Guth, a theoretical physicist at the Massachusetts Institute of Technology (MIT), to explain some unusual features of our universe, especially its surprising homogeneity. For all the clumping of stars and galaxies we see in the night sky, the universe seen through the CMB is extremely uniform—so much so that it has been difficult for physicists to believe that the various pieces of the sky were not all in immediate contact with one another at an earlier point in the universe's development.
Since the theory of cosmic inflation was first advanced, most physicists have come to agree that inflation is the best explanation we have for the observable universe. Yet the hope of acquiring direct evidence of inflation was for a long time regarded as a vain one. In 1997, MIT physicist Alan Lightman wrote that since “the extremely rapid cosmic expansion . . . happened so long ago, we will probably never know with certainty whether that event in fact occurred.”
And yet now, thanks to a set of bold experiments undertaken with the BICEP telescopes, we seem to be closing in on direct confirmation of the theory of inflation. Bock recently discussed the design of the BICEP instrumentation and how it detected a signal from the dawn of time.
How did the BICEP program begin?
It all started with tennis. In 2001 I played tennis every week with Brian Keating, a Caltech postdoc who is now at UCSD. After a few sets, Brian and I would talk about science for a while. He kept bugging me about doing a CMB polarization experiment that would study structures on degree angular scales—portions of the sky larger than the full moon.
More here.