We believe human begins have existed for only a small fraction of cosmic history, because human race has been improving so rapidly in knowledge and t… - Stephen Hawking

There could be whole antiworlds and antipeople made out of antiparticles. However, if you meet your antiself, don’t shake hands!

I realized that if one reversed the direction of time in Penrose’s theorem so that the collapse became an expansion, the conditions of his theorem would still hold, provided the universe were roughly like a Friedmann model on large scales at the present time.

As we shall see, the concept of time has no meaning before the beginning of the universe. This was first pointed out by St. Augustine. When asked: “What did God do before he created the universe?” Augustine didn’t reply: “He was preparing Hell for people who asked such questions.