Scientists have found a celestial fingerprint that not only explains the explosive beginning of time, but also gravity’s microscopic secrets. Nova PBS explains that gravity isn’t just an abstract force. There’s evidence that it’s actually made up of particles.

Video Summary

Scientists have long assumed that gravity is made up of quantum particles, which they called gravitons. A single graviton is too small to defect, so we had no evidence of them until recently. Scientists studying the Big Bang proposed that during the time when all matter was condensed into a cramped ball, there was no gravitational attraction between the universe’s matter. Instead, there was a fierce gravitational repulsion, which eventually forced all matter outward in a momentary event called “inflation.” In the infant years of the universe after the Big Bang, the gravitational waves stretched and contracted parts of space, causing cold and hot spots to form. Where these spots met, the photons produced distinct patterns in the cosmic glow. We can see the final patterns of light today. The swirls in these twisting patterns of lights are called b-modes, and these are the fingerprints that the scientists found.