This is a post that started as an explanation of how multiple coexisting realities can occur, which was a theory of what was going on early in the final season of Lost. The explanations quickly untangled into further puzzles, like "Are there infinite copies of me out there?", and "How was Desmond able to observe one reality from the other?"
Scientists: I hope this rambling isn't so tl;dr as to prevent the little bits of Einsteinian genius from being found and contemplated further. Perhaps one day it will be figured out, and repeated in a concise, sensible blog post.
Schroedinger's Poor Cat -- Explaining the paradox
... or, New(?) ideas on the propagation of probability waves
... or, I never met a lasagna I didn't like.
Take a box. Add: 1 cat; 1 sealed vial of catpoison; 1 molecule of radioactive material that has say a 50% chance of decaying over the next year; 1 radiation detector connected to an apparatus that will break the vial of poison if the radioactive particle's decay is detected. Now close up the box, wait a year, crack it open again, and see if you don't have yerself a dead cat.
This is the basic idea behind the famous Schroedinger's Cat Paradox, a thought-experiment conceived by the actor Arnold Schroedendinger. It was originally suggested to point out the absurdity of the theory and consequences of the Uncertainty Principle in Quantum Mechanics. The principle says that the state of a subatomic particle is impossible to predict and is only determined when it is observed. The particle's state is only a "probability waveform", that collapses into a specific state of reality when observed.
The "cat" thought experiment takes random events in the subatomic realm and through cause-and-effect has results in the human scale of things.
Without clarifying the details of the experiment, it is easy to set it up so that it's clearly ridiculous. You can't just throw the cat in a cardboard box, or shake the box to see if it's alive without opening it. Any clue that can be examined to determine whether the cat is alive or dead, should be considered an observation. And there must always be a probability that the cat can be alive. You can't throw it in without food and wait until you know it must starve.
Speaking of what constitutes an observation, what then constitutes an observer? Must it be a human conscious? No, and it need not even be alive. Anything that can record the state of the cat can be considered an observer. So, the cat too is an observer. It can tell whether it is alive or dead, it doesn't need a human to look at it before its life is determined. The particle detector is an observer too. Anything can be an observer: If the particle decays and emits radiation that has an effect on something else, then that something else is an observer. If the effect can be determined, then the state of the particle is no longer a probability waveform; it has collapsed into a real state. (This suggests the question, what about effects that aren't lasting? Can an event be observed, then completely forgotten, and does this then somehow reinstate a probability waveform? This question might be answerable later in this essay. (See nugget 1, below))
Of course, if the cat is an observer, then its aliveness is never in question, so there should be no probability waveform that collapses when the box is open, and the experiment is not valid. But this need not be the case. If there is no observation made of anything inside the box, then its state is indeterminate to an outside observer, so it is still possible that its state exists only as a probability waveform. How is this possible? One way is through "simultaneously existing alternate realities" in a multi-dimensional "multiverse" thing. The particle may decay and it may not. It may be that each case is played out, simultaneously, in alternate realities. Every such possible event in the universe may occur simultaneously, branching into 2 or more different results, in a sense continuously "spawning" new universes where every possible outcome exists in its own universe. This would require an infinite (or infinitely growing) number of universes, and questions like "Where would they all fit?" make it hard to conceive. Surely, as time goes on, more and more universes would have to exist?
A different way of thinking about this is to consider that the universe exists in multiple dimensions, not all of which we can "see", and rather than say that 2 distinct universes exist, one in which the cat is dead and one in which it is alive, instead both exist in one universe as the superposition of 2 distinct possibilities. The universe would simultaneously contain all possible outcomes of every event ever, not existing as distinct realities as we understand them, but as probabilities of all possible states. The reality that I know and observe would simply be me seeing only the possibilities that make up one combination of all possible states. But being a part of the universe myself, I would also exist only as part of a probability superposition of all possibilities, and so there could be an infinite number of realities I could see, IE. an infinite number of "me"s. (See nugget 2)
Let's just assume for awhile that all of this is true. I'm sure later we'll be able to devise an experiment to test it. It is useful to make assumptions like this, and think about what consequences will result. This leads to thought experiments, which in the past have brought about leaps in understanding ideas that were hard to verify physically.
So by having a particle detector observe the state of the particle, the particle's waveform collapses into either a decayed or not-decayed state, and the cat either dies or lives, respectively. The cat has observed the state of the poison, simply by living or dying. For it, the probability waveform for the particle has collapsed.
Outside the box, if the state of the cat has had no effect on the world, and it is possible that the cat is either alive or dead, then both possibilities still exist in a probability waveform that isn't collapsed until the box is opened. In the multiple universe theory, the cat lives in some universes and dies in others, and we don't know which one we're in until we open the box. This doesn't quite make sense because the act of opening the box can be seen as an event, that should split the universe into multiple realities, but if the cat can still be truly alive or dead, then this may suggest "jumping" between realities... a split occurred earlier for the cat, and now occurs again for the opener of the box.
In the universal superposition theory, instead it means that to us the external observer, the cat has simultaneously lived and died in superposition, and we only observe a single reality from that superposition set when we open the box. If the cat is dead, other realities still exist where it is alive, in the superposition of all things.
Now imagine that you're inside the box. Use your home as an example. Just as anything outside that isn't affected by our state in the box can view us only as a probability waveform, so too do we see everything outside the box as such. We can still measure things like light and gravity penetrating the walls of the house, so some things can be observed between inside and out, and so some waveforms collapse to set a certain reality. As well, we have reasonable expectations of what is possible, so we can be sure that the stars have not suddenly rearranged themselves into a connect-the-dots image of the Mona Lisa, while we were stuck in our cat boxes. More generally, all events outside the house have probabilities, so we can be fairly sure of some things and uncertain of others, to varying degrees. But, it may just be that the reality that exists outside of our houses, that is beyond observation from within, is not determined until we actually go outside and observe it.
This could be happening for every individual who ever puts their self in a probability box with respect to another. We may each have our own specific realities. That is, each reality may be a specific observation of all possible configurations of the universe. Each would be based on prior observations and the possibility of all observable events, and all unobserved events with unobserved consequences still exist only as probability waveforms. As well, the probability value of any waveform should be different in different realities, as past events will make future events more or less likely.
* Idea #1 (with conjecture rating of 95%) Imagine the universe as a world in darkness, and you have a flashlight that follows you around and illuminates every observed part of space-time. Each of us has one of these flashlights, and when we cross paths our realities match as much as needed... I exist in my own reality and you exist in yours, but you also exist in mine, and any part of your reality that can have an effect on mine also exists as reality for me. However, any part of your reality that hasn't yet been observed in mine may still exist only as a possibility in mine. This must be true when we are not connected through possible observation; you may be a cat in a box and are certainly either alive or dead, but to me both cases may be possible.
Some rules for this new universe.
1. The universe is finite. Or, perhaps the universe is infinite. This is not known. If there are only a finite number of particles, and each has a finite set of possible quantum states, then there is only a finite (though mind-bogglingly large) number of possible configurations for the universe.
2. Not everything is possible. Almost anything is possible, because matter can wink into existence. It
may be possible, if not statistically impossible (meaning it's unlikely to ever happen within the average age of the universe), for example that a full-grown whale suddenly appears in space. If this has greater than zero probability, it will happen in some alternate reality. There will be alternate realities occurring for each position in space, and each point in time, and for half-whales and for every combination of whale or penguin or piano, of everything and everything in between. As long as it is possible. If there is zero probability of something happening, it won't happen in any reality. You can't say for example imagine a particular universe, and then say "consider that but with one extra particle", and use mathematical induction to deduce an infinite number of universes. If it is not possible, it doesn't exist in any reality nor probability waveform. The superposition of all states includes only those that are possible.
Rather than to think of an impossibly
large number of universes, each with some weird specific set of features, think of the whole thing all at once, where these weird features have probabilities. All these universes with spontaneously spawned whales and pianos have infinitesimal probabilities, and conceptually, they can be fit into a very
small part of the superposition of all universes.
Experimentation:
Experimenting on this theory is difficult, because possible results of the experiment represent collapsed waveforms. If you imagine 2 people experiencing different possible realities, when you bring them together to compare experiences, you are left with one single observed state of the universe. If they did have different experiences, they will have collapsed into multiple distinct realities, in each of which the two observers experienced only the one shared reality.
There are areas where probabilities are observable. The double-slit experiment is an example where the effects of probability can have observable effects in our reality. I consider this experiment to be the most important that I can think of, and holds a treasure trove of puzzles regarding the probabilistic and uncertain nature of reality. And possibly some of the answers.
Is it possible to devise similar experiments in the larger world? Is it possible to combine 2 separate observations of reality, and to notice the effects of probability wave interference (where certain areas of reality are measurably more probable than others)? More on this some other day.
This idea shrinks the multiverse (and all possible universes) into a conceivable, understandable, small mental model. Things don't exist in specific places, where multiple copies exist elsewhere, each one a little different, and we're left wondering where it all is. Things exist as a superposition of possible states, not as a multiple of single states. It is only observations that limit things to specific states.
How can you conceive of such a universe? How would you store this, if you were modeling it? In a computer simulation of a Newtonian universe, you might store data for each particle in the model: its position, velocity, and anything else like spin or mass that you would need. Then you can run a simulation on the set of data for all particles.
In a simulation of a multiverse with a fixed number of particles, you would do a similar thing, except that instead of storing specific (collapsed) positions and other values, you would store a probability waveform for a particle's position. I'm not sure what that would look like, or how complex it would be. Roughly how many bits of information would it represent? Would it be smooth? IE. would "adjacent" universes have all particles adjacent? Or would there be abrupt differences, such as "particle has decayed" vs. "particle has not decayed", in "adjacent" universes, with no other possibilities in-between? If positions and probabilities can be quantized, it may be that there is no smooth middle "in-between" 2 given possible universes.
Further Nuggets...
(1) Can probability waveforms re-form from collapsed, observed realities?
I think the answer must be yes. I don't think that all subatomic particles are indeterminate until observed, and then spend the rest of their existence in the universe being actualized observed particles.
I think the definition of "observed" would be something involving the ability to have any kind of effect on the observer. Any event that you witness is clearly observed. Any memory of any event is observed. Anything felt, anything that made a mark, anything that caused another observed event, is observed. But anything which is completely unknown, and for which it makes
absolutely no difference how it may have turned out, is not observed. A cat in a sealed box is not yet observed. And I believe that anything that is forgotten, is no longer observed. In a way, if you died and any evidence of
any kind that you existed was destroyed and forgotten (from photographs to the states of any subatomic particles with which you ever interacted), then it no longer matters if you actually existed or not. Perhaps it is just a probability waveform again?
So if you measure a particle and then let it go and lose track of it, never again being able to correlate that particle with the measurement, then a probability waveform is restored. You won't have someone a thousand years in the future observing a particle and saying "Oh! I see that you've been involved in an experiment before!" Such thinking suggests that we can turn a probabilistic universe into a classical one simply by observing it (which actually might be exactly what we do every day) -- and that the transformation is permanent.
(2) There are an infinite number of "me"s in the multiverse.
When we think of multiple universes, we like to think of copies of ourselves doing different things, being different people in some specific way, living different lives. We also imagine ourselves being able to travel to these alternate realities and meet our alternate selves.
I think there are several problems with this line of thought.
- As with the cat-in-a-box ideas, an alternate universe isn't a fully formed universe as big as anything that ever existed; it is only as big as the box. A particular reality only consists of those waveforms that have collapsed. So stepping into another reality would be no different than exploring new areas of your existing reality, except for where the waveforms have collapsed (things that you would know are different).
- The "distance" between realities must grow very fast, in multiple measurable dimensions. A reality where a subatomic particle has decayed may be very close to a reality where it hasn't, but a reality in which Germany won WWI would be inconceivably distant from our reality. It would likely be that much harder to visit, assuming visiting alternate realities was in any way possible. Likewise, a reality where some formative event in your youth occurred differently, would also be inconceivably distant.
- As such a vast number of things can change very quickly over time, it is likely that an alternate "you" would not be "you" in another reality. This argument would require a lot more work, delving into what it means to be "me", and is this entity unique in my own reality, and am I the same "me" as I always was, and always will be? Too many unknowns. However, I don't believe that there is something real, unique, and persistent enough about this "me" that I would be able to identify with corresponding objects in an alternate reality. I don't consider there to be an infinite number of alternate "me"s, because I don't think those alternates are "me".
