+Telescope.jpg) |
The 10-meter South Pole Telescope
and the BICEP (Background Imaging of Cosmic Extragalactic Polarisation)
Telescope are shown against the Milky Way. BICEP2 recently detected
gravitational waves in the cosmic microwave background, a discovery that
supports the cosmic inflation theory of how the universe began. (Image credit:
Keith Vanderlinde, National Science Foundation)
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Approximately fourteen billion years ago, our
universe burst into existence in an extraordinary event that initiated the Big
Bang. In an infinitesimally small fraction of a second, the universe expanded
exponentially to a truly gargantuan size, inflating far in excess of the views
of our most powerful telescopes. All this, of course, was just a theory.
Astronomers from the Background Imaging of
Cosmic Extragalactic Polarisation (BICEP2) radio telescope at the South Pole have
announced the first direct evidence for this cosmic inflation. Their data also
represent the first images of gravitational waves, or ripples in space-time, a
major prediction of Einstein’s 1915 Theory of General Relativity, in effect his
theory of gravity. They have been described as the "first tremors of the
Big Bang." Finally, the data confirm a deep connection between the (until
now) irreconcilable pillars of modern physics: quantum mechanics and general
relativity itself.
"Detecting this signal is one of the most
important goals in cosmology today. A lot of work by a lot of people has led up
to this point," said John Kovac (Harvard-Smithsonian Centre for
Astrophysics), leader of the BICEP2 collaboration.
These ground-breaking results came from
observations by the BICEP2 telescope of the cosmic microwave background - a
faint glow left over from the Big Bang. Tiny fluctuations in this afterglow
provide clues to conditions in the early universe. For example, small
differences in temperature across the sky show where parts of the universe were
denser, eventually condensing into became polarized too.
