> > > Why are some people so adament about a "plenitude" or > a "multiverse" ... what proof is there that is so > convincing that the defenders of this faith are > unwilling to discuss anything else? > > Scott
As Russell mentioned, the multiverse concept is attractive because of its potential to explain a lot of things (e.g., fine-tuned aspects of the universe) which are very difficult to explain otherwise, in a very compelling way. Also, some theories in science, e.g., Linde's chaotic inflation, and Everett's many-worlds interpretation of quantum mechanics, are compatible with this concept as well (although historically proposed for different reasons). Stephen Hawking has actually co-authored a paper in Physics Letters B invoking the multiverse concept to anthropically determine the cosmological constant and the mass density of the universe. Hawking was actually off by a substantial factor (density too low), and he attributes this to using a single field in his calculations instead of many fields, but I was already alarmed by the fact that he wrote that, for lack of an explanatory TOE, he was going to resort to the multiverse concept to select the right density value from all the possible values in the universe ensemble. Fred
