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A Mathematical Answer To the Parallel Universe Question
diewlasing writes to mention that Oxford scientists have proffered a mathematical answer to the parallel universe question that is gaining some support in the scientific community. "According to quantum mechanics, unobserved particles are described by 'wave functions' representing a set of multiple 'probable' states. When an observer makes a measurement, the particle then settles down into one of these multiple options. The Oxford team, led by Dr. David Deutsch, showed mathematically that the bush-like branching structure created by the universe splitting into parallel versions of itself can explain the probabilistic nature of quantum outcomes."
How does this reconcile with reality as we see it?
From my perspective, even if this mathematical "proof" is true, it is only true in the ontological sense, i.e. that these branches can happen and maybe do happen, but not in reality. Then again, I believe the entire basis for the universe is ultimately ontological but that's a different matter.
My point is that these alternate "universes" may only exist in infinitesimally-small times (possibly below the Planck time threshold) and then simply cease to exist again as compared with our reality in the next moment, moment after moment.
Life is like a dream. You never die in your dreams. You never die in your observed life. You just die in alternate universes. This carries on until you reach the next plane of intelligence (wake up) whereupon you realize that there was no mind-body problem to begin with.
Fixed!
Buckle your ROFL belt, we're in for some LOLs.
I would very much like to find the publication of this, or least more details given by the authors if anyone can fine a link.
By the way, Deutsch is a well known physicist, not some crackpot. One of the first problems discovered to be theoretically sped up by a quantum computer is named after him (link).
Occam's razor is useless in situations like this. Basically Occam's razor comes down to a judgment call. 'Which "sounds more plausible"? 'is the question that is asked. To be honest when you get into this branch of physics, even things that have been damn well proven and the knowledge used to build workable devices... the concepts STILL sound impossible.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
(1) Shit happens.
(2) Shit happens. Parallel universes are created. That isn't the choice. It is more like:
(1) (Copenhagen) The act of "observing" a particle at some point between the particle, the measuring apparatus, and your mind, somehow magically causes the particle to collapse from a wave state to a fixed one, without any other action on your part. Nobody has ever explained exactly what an observation is (we are, after all, made of particles too) nor when this happens.
(2) (Multiple worlds) Reality consists of particles in quantum waves of superimposed states. Period. When we observe a particles state, it's state becomes entangled with the state of the particles in our mind, and hence we observe the particle as collapsing to a single state "in each world".
I don't know about everybody else, but the fact that all states can exist, yet I can only perceive them separately, is no stranger to me than that all moments of time exist, yet I can only perceive each one separately.
My theory is that we actually ARE experiencing parallel universes. But the pressures of biological evolution have driven us toward brain structures which hide this fact. Maybe we actually ARE spread out across many different possibilities, but our conscious view of reality is as a single whole. Why? Because it made survival easier, perhaps. Or maybe, individuals with parallel awareness inevitably go insane and die out. Who knows.
Sometimes this parallelism "leaks through," in the form of quantum strangeness. But it's not the universe which is strange, it's actually us. Our brains contradict reality by trying to condense everything and the result is "weird" physics. Is the electron here, or there? Maybe it's both, but our brains decide to interpret it as a concrete one-way-or-the-other, because doing otherwise would require us to be consciously aware of all of reality, something which is probably impossible.
I'm not sure if you were already aware, but there is indeed a concept called "Quantum Darwinism" which helps explain (using the results from quantum decoherence) why we observe things "classically" (single outcomes of experiments, non-entangled macroscopic states, etc.) despite the universe being fundamentally quantum.
Briefly, the theory shows (rigorously) how pseudo-classical states are the only ones that are robust against decoherence. Hence, those are the states that tend to persists for measurable periods of time. And those pseudo-classical states are the ones that give rise to other pseudo-classical states.
Moreover the main developer of these ideas (Wojciech Zurek) describes in his papers how what we typically term "memories" are inherently classical states (it's either "a" or "b"--not a superposition of both). He explains how macroscopic states will tend to be pseudo-classical, so of course any biological (macroscopic) creature will evolve to assume that reality is classical (it's an adaptive advantage and a good approximation of reality).
The point is that these larger-scale superpositions do indeed exist, but that local observers (e.g. instruments, or ants, or humans) can inherently only record/remember classical states, not quantum ones. So, our perception of reality (and memory of reality) is inherently a classical one.
My question would be, are the number of parallel universes countably infinite (same cardinality as the integers) or uncountably infinite (same cardinality as the real numbers)? If countable, this suggests that the number of quantum potential states in the universe are countable, and would seem to lend credence to the idea of an orderly deterministic universe. If uncountable, then the multiverse is infinitely deep - more satisfying, perhaps, in a religious worldview.
Unless, of course, God(s)(ess)(esses) constructed the universe deterministically, to compute something. I suspect it is to create the question to which 42 is the answer.
I have another question, which might sound kind of naive. If we can accept that there are many universes, with new ones sprouting all the time, is there some constraint on how those universes are? That there might be an infinite set within a certain limit? Otherwise, if, in one of these other universes, the laws of physics are different, then those inhabitants or observers might be able to travel between universes -- just like in another universe where the speed of light follows different laws, they might be able to observe the whole universe.
Another poster asked "Why am I experiencing this universe?" To which a poster replied, "Because you are in this one. If you were in a different one you would wonder the same thing. That's the anthropic principle."
So then, if the anthropic principle holds multi-versally, then each observer is trapped in a universe of singular experience. But logically, if anything can change in a forked universe, including the laws of physics, we might imagine a universe where the inhabitants could traverse one or more universes. They might ask, "Why do I experience these universes?" Furthermore, there might be a universe where the laws of physics are such that inhabitants can traverse *any* universe -- a universal universe, so to speak. They wouldn't wonder why they were having a singular experience -- their universe would contain *all* universes. They would be experiencing everything! "Why do I experience everything?"
So what really is different between all the forking universes? They must have some commonality, at least in the laws of physics. If not, then there is the possibility of a universe where you can traverse universes. Am I off base here? Can the laws of physics be different in another universe, even if it is descendant of a universe with laws like ours?
Computers are useless. They can only give you answers.
-- Pablo Picasso
Computers are useless. They can only give you answers.
-- Pablo Picasso
Reality consists of particles in quantum waves of superimposed states. Period. When we observe a particles state, it's state becomes entangled with the state of the particles in our mind, and hence we observe the particle as collapsing to a single state "in each world".
Many people mix those up. Our "mind" doesn't have anything to do with it.
The wave function collapses when a particle interacts with a macrosystem. When two macrosystems are separate from each other, we have to assume the other macrosystem is not coherent with us until contact.
And remember contact *includes* photons reflected off the other macrosystem, so if we see it, otherwise put "observe" it, we're already in contact.
This is why "observation" causes collapse. Not because we're smart.