Black Holes and Young Universes

For the first time, a lecture titled Black Holes and Young Universes was given at the University of California, Berkeley. Augmented by thoughts from Stephen Hawking on this and related topics, it has become part of this collection, composed of 13 essays and an extensive interview. On 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 may give rise to young universes, and the attempts of scientists, initiated by Albert Einstein, to find a unified field theory that could make the macrocosm predictable.