20170216

Number of oxymoronic “multiverses” calculated



PSI Blog 20170216 Number of oxymoronic “multiverses” calculated
Sorry that I totally missed this one for the 2010 PSI Award for Pseudoscience:
Without tongue in cheek or facepalm, MIT blessed a cosmogonical mess that is now over seven years old:
Physicists Calculate Number of Universes in the Multiverse
This actually was published in Physical Review:
Linde, Andrei, and Vanchurin, Vitaly, 2010, How many universes are in the multiverse?: Physical Review D, v. 81, no. 8, p. 083525 [http://link.aps.org/doi/10.1103/PhysRevD.81.083525].
You can get a review copy from arXiv:
Here is the abstract (if you really care):
“We argue that the total number of distinguishable locally Friedmann “universes” generated by eternal inflation is proportional to the exponent of the entropy of inflationary perturbations and is limited by ee3N, where N is the number of e-folds of slow-roll posteternal inflation. For simplest models of chaotic inflation, N is approximately equal to de Sitter entropy at the end of eternal inflation; it can be exponentially large. However, not all of these universes can be observed by a local observer. In the presence of a cosmological constant Λ the number of distinguishable universes is bounded by e|Λ|−3/4. In the context of the string theory landscape, the overall number of different universes is expected to be exponentially greater than the total number of vacua in the landscape. We discuss the possibility that the strongest constraint on the number of distinguishable universes may be related not to the properties of the multiverse but to the properties of observers.”

Egads! Look what you can get published as long as you are a believer in the Big Bang Theory. 
Oh well, at least they are getting closer to accepting that the universe is infinite!




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