Much like the eponymous television series, it appears the big bang just won’t go away. Scientists with the South Pole Telescope collaboration have detected for the first time a subtle distortion in the oldest light in the universe, which may help reveal secrets about the earliest moments in the creation of the universe.

The scientists observed twisting patterns in the polarization of the cosmic microwave background—light that last interacted with matter very early in the history of the universe, less than 400,000 years after the big bang. Though that sounds like a long time by Earth standards, 400,000 years is the blink of an eye, in cosmic terms.

The twisting patterns, known as “B modes,” are caused by gravitational lensing, a phenomenon that occurs when the trajectory of light is bent by massive objects.

A collaboration of researchers led by John Carlstrom, the S. Chandrasekhar Distinguished Service Professor in Astronomy & Astrophysics at the University of Chicago, observed the B modes. It’s being heralded as one of the most significant discoveries this year.

“The detection of B-mode polarization by South Pole Telescope is a major milestone, a technical achievement that indicates exciting physics to come,” Carlstrom said.

The cosmic microwave background is a sea of photons (light particles) left over from the big bang that pervades all of space, at a bone-chilling temperature of minus 270 degrees Celsius (just 3 degrees above absolute zero). Measurements of this ancient light have already given physicists a wealth of knowledge about the properties of the universe. Tiny variations in temperature of the light have been mapped across the sky by multiple experiments, and scientists are gleaning even more information from polarized light.

B modes can’t be generated by simple scattering of normally polarized light (which results in easier to observe E modes), instead pointing to a more complex process—hence scientists’ interest in measuring them. Gravitational lensing the process by which light is bent by a massive object), it has long been predicted, can twist E modes into B modes as photons pass by galaxies and other massive objects on their way toward earth. This expectation has now been confirmed.

The more elusive B modes would provide dramatic evidence of inflation, the theorized turbulent period in the moments after the big bang when the universe expanded extremely rapidly. Inflation is a well-regarded theory among cosmologists because its predictions agree with observations, but thus far there is not a definitive confirmation of the theory. Measuring B modes generated by inflation is a possible way to alleviate lingering doubt.

“The detection of a primordial B-mode polarization signal in the microwave background would amount to finding the first tremors of the Big Bang,” said the study’s lead author, Duncan Hanson, a postdoctoral scientist at McGill University in Canada.

B modes from inflation are caused by gravitational waves. These ripples in space-time are generated by intense gravitational turmoil, conditions that would have existed during inflation. These waves, stretching and squeezing the fabric of the universe, would give rise to the telltale twisted polarization patterns of B modes. Measuring the resulting polarization would not only confirm the theory of inflation—a huge scientific achievement in itself—but would also give scientists information about physics at very high energies—much higher than can be achieved with particle accelerators.

The measurement of B modes from gravitational lensing is an important first step in the quest to measure inflationary B modes. In inflationary B mode searches, lensing B modes show up as noise. “The new result shows that this noise can be accounted for and subtracted off so that scientists can search for and hopefully measure the inflationary B modes underneath,” Hanson said. “The lensing signal itself can also be used by itself to learn about the distribution of mass in the universe.”