Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-02-07
In "Science and Ultimate Reality: From Quantum to Cosmos", honoring John Wheeler's 90th birthday. J. D. Barrow, P.C.W. Davies,
Astronomy and Astrophysics
Astrophysics
18 pages, 8 figs. A less technical adaptation is scheduled for the May 2003 issue of Scientific American. Version with full-re
Scientific paper
I survey physics theories involving parallel universes, which form a natural four-level hierarchy of multiverses allowing progressively greater diversity. Level I: A generic prediction of inflation is an infinite ergodic universe, which contains Hubble volumes realizing all initial conditions - including an identical copy of you about 10^{10^29} meters away. Level II: In chaotic inflation, other thermalized regions may have different effective physical constants, dimensionality and particle content. Level III: In unitary quantum mechanics, other branches of the wavefunction add nothing qualitatively new, which is ironic given that this level has historically been the most controversial. Level IV: Other mathematical structures give different fundamental equations of physics. The key question is not whether parallel universes exist (Level I is the uncontroversial cosmological concordance model), but how many levels there are. I discuss how multiverse models can be falsified and argue that there is a severe "measure problem" that must be solved to make testable predictions at levels II-IV.
No associations
LandOfFree
Parallel Universes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Parallel Universes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Parallel Universes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-294452