Black Holes May Be EvidenceThe trouble began with those bothersome boogeymen of the cosmos, black holes. But in the 1970s, famed astrophysicist Stephen Hawking realized that black holes aren’t entirely black. Black holes have a surprising property: their entropy is proportional to their surface area, not their volume. Now, let’s say you’re trying to solve a very complicated problem within that universe, like how quantum gravity works. Quantum gravity is an understanding of gravity applied to the smallest things in the universe, such as subatomic particles.