“is about the gravity of empty space, the gravity of the vacuum. And the vacuum is a concept that we address in and quantum mechanics. Quantum mechanics is physics on microscopic scales, while Einstein's theory of general relativity ... is physics on macroscopic scales. These two theories are both great, but they don't work together. We don't have what's called a quantum theory of gravity, the way the two are united. However, dark energy actually requires you to use both of these branches of physics. So our hope is that by observing how the universe actually does physics at that interface, we will learn how to unify those.”
“We know there is gravity because apples fall from trees. We can observe gravity in daily life. If we could throw an apple to the edge of the universe, we would observe it accelerating.”
Adam Riess
“I think . I never would have guessed it. Even as an undergraduate, once I’d learned a little physics, I would have thought that the universe was eternal, static, and always in equilibrium. So in gradu...”
Adam Riess