The double split slit experiment. You fire particles or photons through two slits, and you put a screen behind those slits to see what happens. And that interference pattern arises even if you fire one particle by one particle. So there's a genuine uncertainty in which slipped the particle in the particle construe. The second level is really once you start probing once you add a layer to the double slit experiment and you probe yeah okay let me add a detector. Let me check to true which slit this particle really came. When you cheat the particle will adapt in a way and the interference pattern will disappear.
Perhaps the biggest question Stephen Hawking tried to answer in his extraordinary life was how the universe could have created conditions so perfectly hospitable to life. In order to solve this mystery, Hawking studied the Big Bang origin of the universe, but his early work ran into a crisis when the math predicted many big bangs producing a multiverse — countless different universes, most of which would be far too bizarre to harbor life. Holed up in the theoretical physics department at Cambridge, Stephen Hawking and his friend and collaborator Thomas Hertog worked on this problem for twenty years, developing a new theory of the cosmos that could account for the emergence of life.
Shermer and Hertog discuss: what it was like working with Stephen Hawking • Darwinian model of cosmology • time • What banged the Big Bang? • cosmic inflation and multiple universes • how to reconcile Einstein’s relativity theory of gravity and quantum theory • Hawking’s no-boundary theory • why the universe appears designed • Feynman’s sum over histories approach to quantum physics • Is there purpose in the cosmos? • Why is there something rather than nothing?
Thomas Hertog is an internationally renowned cosmologist who was for many years a close collaborator of the late Stephen Hawking. He received his doctorate from the University of Cambridge and is currently professor of theoretical physics at the University of Leuven, where he studies the quantum nature of the Big Bang. He lives with his wife and their four children in Bousval, Belgium.