billswift comments on Many Worlds, One Best Guess - Less Wrong

12 Post author: Eliezer_Yudkowsky 11 May 2008 08:32AM

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Comment author: billswift 11 May 2008 03:50:37PM 4 points [-]

"If the same laws are true at all levels - i.e., if many-worlds is correct - then when you measure one of a pair of entangled polarized photons, you end up in a world in which the photon is polarized, say, up-down, and alternate versions of you end up in worlds where the photon is polarized left-right. From your perspective before doing the measurement, the probabilities are 50/50. Light-years away, someone measures the other photon at a 20째 angle to your own basis. From their perspective, too, the probability of getting either immediate result is 50/50 - they maintain an invariant state of generalized entanglement with your faraway location, no matter what you do. But when the two of you meet, years later, your probability of meeting a friend who got the same result is 11.6%, rather than 50%.

"If there is only one global world, then there is only a single outcome of any quantum measurement. Either you measure the photon polarized up-down, or left-right, but not both. Light-years away, someone else's probability of measuring the photon polarized similarly in a 20째 rotated basis, actually changes from 50/50 to 11.6%."

I don't see how you claim many-worlds gets you around the special relativity problem, the measurements can only be compared within one world - how would postulating other non-interacting (after the split) worlds help?

Also I have been having trouble following your posts. Your writing here has the same problem many weirdos (IDers, perpetual-motion-machine makers, etc) has. Any facts and arguments are getting lost in your wordiness. You might want to try to post brief explanations of what **specifically** your claims are in each post (maybe as occsasional summing-up posts).