What is Multiverse Theory?

• a theory in which our universe is not the only one, but states that many universes exist parallel to each other.

Who proposed it?

• concept derived originally, by philosophers in prior centuries

• American Psychologist William James coined the term “Multiverse”

• David Deutsch was the first to discover and contribute physical evidence to support the theory on a quantum scale

• Popularized by science-fiction author Michael Moorcock

MAX TEGMARK’S CLASSIFICATIONarranged such that subsequent levels can be understood to encompass and expand upon previous levels

Level I: Beyond our cosmological horizon

• space is so big that the rules of probability imply that surely, somewhere else out there, are other planets exactly like Earth.

Level II: Universes with different physical constants

• regions of space are continuing to undergo an inflation phase

• space between us and the other universes is literally expanding faster than the speed of light — and they are, therefore, completely unreachable

• The findings of eternal inflation mean that when inflation starts, it produces not just one universe, but an infinite number of universes.

Level III: Many-worlds interpretation of quantum mechanics

• a consequence of the many worlds interpretation (MWI) from quantum physics

• every single quantum possibility inherent in the quantum wavefunction becomes a real possibility in some reality.

Level IV: Ultimate Ensemble

• it would follow fundamentally different mathematical laws of nature than our universe

• any universe that physicists can get to work out on paper would exist, based on the mathematical democracy principle: Any universe that is mathematically possible has equal possibility of actually existing.

Drawbacks

• its impossible to test the existence of these parallel universes because its believed that the space between these universes are spreading out faster than the speed of light.

• Accepting multiverse theory would be accepting the naturalistic side of the theory rather than the scientific part.(Its more cosmology than astronomy)

Compared to the Big Bang

• MVT states that new universes form through the collapse of giant stars and the formation of black holes. Inside the singularity in black holes could be a permutation of the Big Bang

• The Big Bang talks about a universe that is continually expanding while the MVT talks about multiple other universes.

Citations

• "The Theory of Parallel Universes." - For Dummies. Web. 16 Apr. 2012. <http://www.dummies.com/how-to/content/the-theory-of-parallel-universes.html>.

• Tegmark, Max (May 2003). "Parallel Universes". Scientific American.

• "Multiverse." Science. Web. 16 Apr. 2012. <http://www.allaboutscience.org/multiverse.htm>.

• "Sean's Multiverse." Web. <http://www.astronomy.pomona.edu/Projects/moderncosmo/Sean%27s%20mutliverse.html>.