"We have evidence of what we call 'the gravitational wave background,' which is a hum of ... New Mexico. (Education Images/Universal Images Group via Getty Images)NANOGrav scientists detected ...

Gravitational waves from inflation ... light from the cosmic microwave background -- relic radiation left over from the Big Bang that created our universe. Image released March 17, 2014.

This research has provided further evidence of a background "hum" of gravitational waves that permeates the universe. As such, it could grant new insights into the universe's earliest black holes ...