Probability and the Many-Worlds Interpretation of Quantum Theory

Two works related to the concept of probability in the framework of the many-worlds interpretation are presented. The first deals with recent controversy in classical probability theory. Elga and D. Lewis argues that Sleeping Beauty should have different credences for the result of a fair coin toss in a particular situation. It is argued that when the coin is replaced by a quantum coin, the credence is unambiguous and since one should not expect a difference between classical and quantum coins, this provides a particular resolution of the controversy. Second work is an analysis of a recent criticism by Byrne and Hall of Everett-type approach presented by Chalmers. It is shown that the criticism has no universal validity and that the Byrne and Hall rejection of any Everett-type interpretation of quantum mechanics is unfounded.