Physicists have long speculated whether or not gravitational wave imprints could be detected in the cosmic microwave background, or CMB, which is the leftover light from the Big Bang. The CMB is the faint glow in the sky.

Gravitational wave imprints are curling in the polarization of the CMB. This curling can only be caused by gravitational waves produced by inflation, which supports the theory that the universe is expanding.

Stanford University physicist Chao-Lin Kuo designed the device, BICEP2, that would detect these gravitational waves.

Although this information gives more hard evidence to the theory of inflation, it is still in its infancy, and other tests are still being conducted to confirm it.

Researchers for the BICEP2 found such strong signals of polarization in their data that they held off publication for more than a year to try to figure out if there were any other explanations for such distinct patterns. After retesting with another detector and receiving the same results, they felt confident in finally releasing their findings.

Leaders in the field have praised the new discovery. Some — including Marc Kamionkowski, who predicted in 1997 that gravitational waves could be found — are saying this discovery is worthy of a Nobel Prize.