What follows when quantum theory is applied to the whole universe? This is one of the greatest puzzles of modern science. Philosophers and physicists here debate the Everett interpretation of quantum mechanics, according to which this universe is one of countlessly many others, constantly branching in time, all of which are real.

What would it mean to apply quantum theory without restriction to the whole universe? What then does realism about the quantum state imply? This book brings together an illustrious team of philosophers and physicists
to debate this question. All the contributors agree on realism and on the need, or the aspiration, for a theory that unites micro- and macroworlds. But they disagree on what this implies. Some argue that if the SchrAdinger equation has unrestricted application and if the quantum state is taken to be something physically real then this universe emerges from the quantum state
are compromised; the concept of probability itself is in question. There are realist alternatives to many worlds theory, among them theories that leave the SchrAdinger equation unchanged.
Twenty original essays, accompanied by commentaries and discussions, examine these claims and counterclaims in depth. They are organized according to questions of ontology
alternatives to many worlds

written with great clarity by some of the best minds in contemporary foundations of physics... a fine read, summarizing nicely the state of the art in one of the most radical no-collapse interpretations of quantum theory.