Pattern of Ancient Light Discovered

After years of searching, researchers detected twisted patterns of ancient light known as B-modes, which form as the pull of matter distorts light as it travels billions of years to reach Earth.

Previously, scientists predicted two types of B-modes, including the ones recently discovered, which were created a few billion years into the universe's 13.8 billion years of existence. The other kind of B-modes, called primordial, are believed to have been created fractions of a second after the Big Bang.

"This latest discovery is a good checkpoint on our way to the measurement of primordial B-modes," Duncan Hanson, a professor at McGill University and lead author of the new report published in Physical Review Letters, said in a statement.

In the study, the researchers were searching for the kind of polarized light created by matter in gravitational lensing, in which the pull of matter distorts light's path.

Because the signals are faint, Hanson and his colleagues used the Herschel Space Observatory's infrared map of matter to guide their search and the South Pole Telescope to spot the signals, resulting in the first detection of B-modes ever.

The discovery of B-modes is important in understanding how both normal and dark matter are distributed throughout the universe. Furthermore, the researchers hypothesize that B-modes may be imprinted with insights into how the universe was born.

Going forward, scientists hope to detect primordial B-modes next.

"These beautiful measurements from the South Pole Telescope and Herschel strengthen our confidence in our current model of the universe," said Olivier Doré, a member of the US Planck science team at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "However, this model does not tell us how big the primordial signal itself should be. We are thus really exploring with excitement a new territory here, and a potentially very, very old one."