On 08 Jul 2008, at 01:08, Brent Meeker wrote:
> > Ronald Held wrote: >> I am giving a talk on the Multiverse to Star Trek fans in several >> weeks. I would appreciate any advice and suggestions, since as of >> now, >> I have an outline based on Tegmark's four levels. >> >>> >> > > One thing I would avoid is presenting the multiverse (of any level) > as the > latest "gee-whiz, science has discovered that..." It is interesting > speculative metaphysics. Good fodder for SciFi fans but not yet > science. I disagree. It is the collapse axiom which has been a speculation all along: to avoid macroscopic superpositions. I totally agree with David Deutsch that QM is the science of parallel universes, except that I have abandoned eventually the very notion of "primary physical universe", and I prefer the many histories or many dreams wording which fit better with respect to the mind-body problem in the mechanist frame. I am not saying that the MW solves all conceptual problems of QM 'course. But the belief in the existence and unicity of the Physical Universe is equivalent to saying that QM is false, and up to now, *that* is the speculation. Then with just the digital mechanist thesis, the existence of the many dreams is even more obvious. That physics has to emerge from those many dreams is (apparently) a bit less obvious, but I am not even sure given that I have not yet heard any objection but wishful thinking. If I look to a particle in the state "(UP + DOWN)", the state "I cross (UP + DOWN)" evolves (by SWE) to: "I-seeing-UP cross UP + I-seeing-DOWN cross DOWN", I don't see how to avoid this without abandoning QM. The collapse can be explained *phenomenologically* (first person plural) through MW + decoherence. And if I make a decision based on what state I measure on the particle, the divergence will propagate. And Weinberg has given a convincing argument that once SWE is made slightly non linear, then, not only we keep the Many Worlds/Dreams, but interaction is made possible between them (falsifying then thermodynamics though: that is why I don't take that the delinearisation of the SWE idea very seriously). That's speculation. Bruno http://iridia.ulb.ac.be/~marchal/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to [EMAIL PROTECTED] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list?hl=en -~----------~----~----~----~------~----~------~--~---