Then, in the 1980s, an old observation of Einstein’s was resurrected in a sparkling new form, giving rise to what has become known as inflationary cosmology. And with this discovery, credit for the bang could finally be bestowed on the deserving force: gravity. It’s surprising, but physicists realized that in just the right environment gravity can be repulsive, and, according to the theory, the necessary conditions prevailed during the earliest moments of cosmic history.
