Photons' journeys across the universe help unravel cosmological mysteries
Friday, February 14, 2014 - 09:30
in Astronomy & Space
(Phys.org) —The faint background glow that exists throughout the Universe, called the Cosmic Microwave Background (CMB), is made of photons that have been scattering since the universe was just 400,000 years old. Now in a new paper, physicist Liang Dai at Johns Hopkins University in Baltimore, Maryland, has shown that the polarization of these photons is rotated as they travel by things such as gravity waves and cosmic matter flows. By accounting for this rotation effect when observing the CMB photons, scientists may be able to investigate parts of the Universe that might otherwise remain unknown.