Light born at the moment of the Big Bang has traveled to us for almost 14 billion years. But along the way, it passed through the gravitational fields of galaxies and clumps of dark matter, which bent its rays. To an observer, this looks like an image stretched and smudged by an old window pane.
A new algorithm based on a neural network ‘wipes’ that glass clean. It trains on computer simulations of distorted cosmic microwave background radiation, then reconstructs the original pattern — from before the first stars appeared. The method works tens of times faster than its predecessors and isn’t bothered by small changes in fundamental parameters, such as the distribution of dark matter and the rate of expansion of the universe.
Every second, millions of particles of the cosmic microwave background (echoes of the Big Bang, cooled to a barely noticeable radio hiss) pass through your body.
By removing the gravitational lens, one can imagine looking at the universe before its birth, like in ‘Interstellar,’ where distorted light opens a path to another dimension.