David Hogg

New York University, Professor

What was there before the Big Bang?

Nearly everything we know about the Universe comes from the analysis of the light that happens to fall onto the Earth from space. Despite the fact that we can't directly do experiments or sample return, we know an immense amount about the Universe. For example, we know with great confidence that the Universe is expanding, that it contains black holes and dark matter, and that all of the heavy elements (like oxygen and iron) were created in stars. Our success in deriving confident conclusions from indirect evidence makes it possible that we may someday know with comparable confidence what came before (or lies outside) the observable Universe.