I watched this Google Tech Talk recently - Quantum Conspiracy
Now I have done some investigating concerning these ideas and their implications, and also have dug up two relevant science papers written on this subject. You'll have to look them up on Google as I cannot yet post multiple links:
The Ithaca Interpretation of Quantum Mechanics
Quantum Information Theory of Entanglement and Measurement
What I would really like to know is if this theory is at all plausible, and if Ron in the presentation above is correct would this in any way imply that time is static in the Multiverse in that it is timeless?
I guess this has more to do with relativity than with quantum mechanics, but this wave function I take it according to the video and papers is a four-dimensional thing. One of those dimensions emerges as “time” in our classical universe(s), but which dimension that is depends on your frame of reference. A classical universe is a little slice of the wave function that contains macroscopic systems in classical correlation with each other across all four dimensions (as described by QIT). It is these correlations that give the illusion that time is passing.
This is covered briefly(in the talk above) at the end of the talk where he points out that the physical mechanism that produces Einstein’s “spooky action at a distance” also produces the “spooky action across time” that causes the past to appear as a coherent consistent whole, but to recap: If you and I look at something and agree that it is green, it is tempting to think that the reason we agree on this is that the thing we are looking at does in fact exist and is in fact green. And for macroscopic things that’s a pretty good approximation. But for particles it’s not. The reason you and I can look at a photon and agree that it’s vertically polarized is NOT that the photon in fact exists and is in fact vertically polarized, it’s because you and I comprise a macroscopic system of mutually entangled particles (by virtue of having interacted with the same photon) and so, by QIT, when we trace over (i.e. ignore) the photon we get a mathematical description of us as two classically correlated systems.
The same thing happens to “you” at different instances in “time". You are not in fact a physical being, you are a macroscopic system of mutually entangled particles (or, to be strictly correct, mutually entangled components of the wave function) which, as described by QIT, behave as if they were a set of classically correlated systems. The reason you at any instant in time feel like a material being that has existed in the past is because you have memories, which are part of your (classical) state, and those memories correlate with other things in the universe, like the pictures in your photo album. These correlations that persist across time are the reason that you believe the past to be real (as opposed to, for example, your dreams which don’t persist across time in the same way). Again, it is tempting to believe that the past is coherent because the things that you remember existing in the past did in fact exist in the past. But that is not the case. The reason the past is coherent is, again, because “you” at any instant in “time" are in classical correlation with parts of the wave function that “you” call “the past”. That is the definition of the past. That is the reason that time appears to flow in one direction despite the fact that all the laws of physics are time-symmetric. The “past” is simply that part of the wave function that “you” are correlated with at any particular instant (or, to phrase it more accurately, that any particular you is correlated with).
The simulation(Multiverse) cannot “go on forever” because it does not “go on” at all. The wave function is static. Time is an illusion that emerges when you slice up the wave function in a particular way that yields subsets of itself that behave like classically correlated systems across four dimensions. But these systems do not have the same metaphysical status as the wave function itself, so it is a sort of “category error” to try to apply words from one (like “beginning” and “end”) to the other.
My problem with this is that I always interpreted the Multiverse(if one even exists) as predicted by string theory to be eternal in that it doesn't require a cause and that time has no beginning and no end. However time cannot be static in this Multiverse because nothing would ever happen or everything would happen at once. In that sense inflation and time within each Universe would not make sense within the Multiverse and would be non-observable within the Multiverse. This doesn't make any sense to me at all. So time cannot be static in the Multiverse or linear like an arrow. So something doesn't add up with QIT.
Any support or clarification here from a real physicist or someone with more physics knowledge than myself would be greatly appreciated.
Thanks in advance