The recent book The Hidden Reality: Parallel Universes and the Deep Laws of Cosmos by Brian Greene is presented as follows:
- The possibility of other universes existing alongside our own like holes in “a gigantic block of Swiss cheese” seems more likely every day.
- Beginning with relativity theory, the Big Bang, and our expanding universe, Greene introduces first the mind-blowing multiplicity of forms those parallel universes might take, from patchwork quilts or stretchy “branes” to landscapes and holograms riddled with black holes.
- With his inspired analogies starring everyone from South Park’s Eric Cartman to Ms. Pac-Man and a can of Pringles, Greene presents a lucid, intriguing, and triumphantly understandable state-of-the-art look at the universe.
- …exciting and rewarding…captures and engages the imagination. (New York Times)
- If extraterrestrials landed tomorrow and demanded to know what the human mind is capable of accomplishing, we could do worse than to hand them a copy of this book. (New York Times Book Review)
- Greene’s success at explaining the patently inexplicable lies in the way he delightfully melds the utterly bizarre and the utterly familiar. (Providence Journal)
- Exotic cosmic terrain through which Greene provides a lucid, intriguing, and triumphantly understandable state-of-the-art look at the universe. (Publisher’s Weekly (Starred Review))
- Greene has something fresh and insightful to say about pretty much everything. (Sciencefiction.com)
- The Hidden Reality is an accessible and surprisingly witty handbook to parallel universes. (Toronto Star)
- … a rare accomplishment in science writing for a popular audience. (Amazon.com, Best Books of the Month, January 2011)
Here is my impression: The book is about parallel worlds, parallel universes or multiple universes, other worlds than the one we happen to live in and worlds which we cannot contact. Greene explains the background to this strange idea as follows:
- A striking fact is that many major developments in fundamental theoretical physics — relativistic physisc, quantum physics, cosmological physics, unified physics, computational physics — have led us to consider one or a variety of parallel universe.
What Greene is referring to is the basic problem of modern physics of the interpretation of quantum mechanics with the Copenhagen Interpretation (CI) as the official answer dictated by Niels Bohr, under heavy but fruitless protests from Einstein and Schrödinger, based on Max Born’s view of the wave function as a probability distribution subject to so called collapse into physical observables.
The Schrödinger Cat of CI is supposed to be in a superposition of double states of both life and death,
and collapses to either life or death in the world of the observer. This leaves room for the (utterly strange) idea that maybe if the cat collapse to death in our world, it is saved to life in another parallel world, as if in a multiverse all possibilities will be real somewhere.
This idea was taken up by Hugh Everett in his Many-World Interpretation (MWI) as variant of CI. We see that MWI reflects the idea that in Einstein’s words “God is playing dice” and in this game there is always a parallel world were all our missed opportunities and feared tragedies will be true.
So, MWI and parallel universes is in a way a logical consequence of the probabilistic interpretation of the wave function, and since parallel universes of missed opportunities must be viewed with great suspicion, we are led to view also CI with great suspicion.
Is there then any alternative to a probabilistic CI interpretation of the wave function, with its utterly strange consequence of MWI? Yes, there is: Many-Minds Quantum Mechanics (MMQM) uses a different solution concept for the Schrödinger wave equation which allows a deterministic interpretation of the wave function. In MMOM there is only one world, and no worlds of all possible catastrophies.
Isn’t this something to take along as consolation when now taking off into the Darkness of Northern Christmas? See also: