Black Holes and Young Universes

The lecture titled Black Holes and Young Universes was first delivered at the University of California, Berkeley. Supplemented by the reflections of Stephen Hawking on this and related topics, it has become part of this collection, composed of 13 essays and an expanded interview. In these pages, the most famous astrophysicist of our time interprets the most likely models of the structure of the Universe. This is a continuation of the dialogue with the reader that began in the book A Brief History of Time. The author reflects on imaginary time, how black holes can give life to young universes, and the attempts of scientists, initiated by Albert Einstein, to find a unified field theory that could make the macrocosm predictable.