Just Another Fish

I posted this as a comment in Gillian K’s LJ, and I thought I might as well put it here, too:

I take the standpoint that reality is both fully determined (from an objective POV), and probabilistic (from an internal observer’s POV).

I think about this sort of thing a lot, too:

Our universe is so arbitrary that it is easier (ie, simpler and more elegant) for a multiverse to exist which contains it than for it to exist by itself.

The laws of QM suggest the existence of these universes as a continuation of the wavefunction beyond what we observe (ie, our universe is just one choice of slices among many in the whole multiverse).

Phenomena producing your current mental-state exist in infinitely many of these possible universes. By the whole identity of indiscernibles thing, since it is impossible to distinguish between these universes it is valid to say that you exist in all of them simultaneously.

This cloud of possible realities is unstable: your mind is a dynamic entity and so each change will cause a shift in the cloud. Each observation prunes away the universes which no longer fit (they contain differentiated versions of you, each of which has its own cloud — even the dead ones, which has the trivial, empty cloud).

(I would not be surprised if there is something about the nature of our consciousness that forces some sort of quantum-type interaction between elements of the cloud, and that this is what causes us to perceive a universe that obeys quantum laws, This is a kind of interesting kink on the weak anthropic principle.)

If you die in some universes, there will always have been alternatives in the cloud where you continue to exist. Since it is impossible to experience being dead, you will always experience continuity of consciousness.

Welcome to immortality. Please enjoy your stay.

I have decided to inflict more crap on you all!

As stated a couple of posts ago, I adhere to the Many Worlds interpretation of Quantum Mechanics.

Let me introduce the concept of the Block Universe from General Relativity:

Since space-time is a combined continuum, you can view the universe, from start to finish (if either end tends to inifinity, it doesn’t really matter) as an unchanging, 4-dimensional ‘block’. It is interesting to consider what new shapes and symmetries can be seen from this perspective, how the universe might make more sense when seen like this. Events are no longer disconnected, semi-causal things but a tapestry of flows and geometries.

Now think about combining the two concepts. What we have now, really, is the wavefunction of the universe taken to the limit of its evolution. Again, one might say that this is really the proper way to look at it, that the time-wise evolution we generally calculate is a parochial, limited aspect. One might also argue that, since one can infer either from the other, they are entirely equivalent: that, in the end, there is no preferred level or way to look at things, just viewpoints that highlight different characters.

Of course, this is not entirely true, and the key here is ambiguity: where a perspective allows for alternative contexts or outcomes, we are clearly only getting a partial view of the whole. This is part of what the MWI is all about.

Something that I’m interested in is how much of quantum mechanics can be derived on the basis of consciousness itself. Part of being a mind is that we are self-contained informational entities: there is a divide between the universe and ourselves. At a basic level, all we have is our qualia, our sense of being. There are many ways this qualia can be brought about, from radically differrent substrates such as brains, computer simulations, or random patterning of a dust cloud, to rather minor diferences such as the position of an atom 2,000 miles away.

I would argue that, on the principle that that which makes no difference is no difference, since all these possibilities are by definition hidden from you by layers of ambiguity, they are all true (at least, all that are, in some sense, possible). You carry with you a cloud, a train of possible contexts.

Consciousness is not just a result of chance - it is structured and brought about by some sort of underpinning logic. It must work on some level, according to some sort of informatic basis. Why do we see the wavefunction of the universe splitting up by some sort of information-preserving rationale? I think this is because our minds operate to the same fundamental level, and that alternative evolutions of the wavefunction destroy the coherence of the mind. They could well exist (in fact, why not?) but we could never know about them except by indirect inference. It could b argued that the physical laws of the universe are nothing more than a reflection of the logic of consciousness and the way it causes its context-train to interfere with itself.

I’m hungry. Time to eat!

At some point I am going to have to do a write-up of Xmas and New Year’s… but not yet. Think I need to do something different. So…

What is it that people have against the idea of other universes? As a proponent of the Many Worlds Theory (my beliefs actually go further than that, into what might be called an All Possible Worlds Hypothesis), I find the most common counter-argument — that it grievously breaks Occam’s Razor — ironically amusing.

Consider geometry. Imagine someone discovering triangles and then being introduced to squares, pentagons, hexagons, … and treating each new shape with the same surprise and amazement*. This seems ridiculous because they are all clearly part of the same over-arching area of maths: polygons, which are themselves nestled within overlapping shells of more general entities still.

Even more silly is that of someone counting and being shocked as the act of adding 1 uncovers yet another number.

Why am I stressing such obvious and inapplicable points? Because as far as I’m concerned, they are applicable.

One thing that needs pointing out is that the MWI does not propose that there are extra universes out there; it proposes that the (Classical) universe we see is but a part of a larger one. The real problem with other interpretations of Quantum Theory is trying to explain how the wavefunction ‘collapses’; why do all the other possibilities disappear, and how is it chosen which one actually occurs. The explanations for this amount to little more than hand-waving. The only reason to assume the other possibilities go away is because we no longer observe them, but that’s not an adequate basis for dismissing them. We have equations for showing the propogation of the wavefunction that work flawlessly and elegantly up till that point, so we should not be so hasty in throwing them out of the window. It takes far less effort and assumptions to simply try to continue with them as they are.

So, picture the wavefunction. This is pretty much impossible, but imagine reality as a shifting, multi-dimensional wave of connections and potentiality, diverging and converging, interfering with itself and always expanding the sphere of the possible. The ‘collapse’ is just what we would expect to see if the wavefunction, at some information-containing threshold, partitions itself into incommunicado slices. It’s elegant and cuts down on all the things we need to believe in.

From my point of view, it makes little sense to raise up the single reality we see and enshrine it as some sort of monolith of existence. It is complex and arbitrary, just crying out for some context to render it plausible. And, no I don’t see a creator god as a solution. It has edges like a jigsaw puzzle, that to me only make sense if we allow the universes next door (next door but not seperate, still part of the same block) as much reality as this one. And, besides, what is existence? What really is there to differentiate something that is ‘real’ between something that ‘could’ exist? Are real things run on some special, privileged sort of substrate (and what decides between them?)? Are they made out existinos? People seem misled by the illusion of solidity, by the billiard-ball view of reality, that real things have some sort of elemental, hard, substance to them. If considered in depth that is absurd, as it just pushes the question back a stage further.

OK, next-up: what has been happening lately.

* Some people are easily impressed.

While you all whet your appetites for my next instalment, why not have a look at this short and very readable guide to quantum mechanics?

It covers the various interpretations of QM and it will probably tell you a great deal about how I view the universe if I tell you that I think they’re all true insofar as they’re actually possible). In fact, one of the interpretations is called ‘Consistent Histories’; mine might be called ‘Consistent Interpretations’. My favourite, however, remains the MWI - if they can all be formulated in terms of each other, then this one is at least still the most elegant and least encumbered.

Oh, and if you want to look at something funny instead, I quite recommend the Perry Bible Fellowship.

I did promise a while back that I’d start talking about my ideas and stuff.

The trouble is that I’m not sure where to begin - I talked a lot of this stuff to death years ago, and while I think it all holds up as a very elegant and compelling edifice, it’s very hard to deconstruct and discuss. This is possibly because it involves a bundle of intuitive yet elusive concepts that I don’t really think about in a verbal sense; they’re somewhere between maths, logic and dynamic models. In other words, I feel it in my gut.

I imagine religious people would describe their faith in much the same way.

So… again, where to begin?

It’s probably best if rather that attempt an analysis straight away, I talk about what I believe and see what comes out. At this point, I do not know if I am writing for myself, my friends, or the hordes of surfers who visit this blog every day. In a way it’s kind of like the diary you secretly hope people will head and… ????? well, step 3 (profit!) is that somehow everything becomes OK in your life.

Sorry, this space is for metaphysics only. I’ll quit with the me-talk.

First off: do I believe in god? Well, no, clearly not… though I do have some sympathies with Spinoza’s Pantheism, wherein reality and god are one and the same thing. It’s the only thing that would make sense, though it obviously requires structural justification (why would reality be god-shaped?).

The questions that really interest me are: what is reality? What are minds? How do they relate to each other?

The third question is not as asinine as it seems. Clearly, minds are part of reality so youcould say that it’s a category error to even ask that. Not so. The reason being is basically the Weak Anthropic Principle - “conditions that are observed in the universe must allow the observer to exist.” What we witness of reality is limited to those parts of it in which we can exist. If you were stubborn, you could argue that this is a facile truism but it alters things. Most people hold that time is a simple linear beast, mainly because they have never had a reason to consider otherwise. It’s common sense - there’s the past, the present, and the future and they form a continuous line.

Both relativity and quantum mechanics would argue otherwise. (There now begins a lengthy discussion of this)

We all know that space-time can be warped, that the speed of time depends on your viewpoint. Put simply, the faster you move in space, the slower you move in time. Photons, travelling at c, do not experience time at all. They are emitted, they are absorbed. Everything that happens inbetween is instantaneous. Different observers witnessing the same events can disagree on even such basic things as causality - does A happen before B? It depends where you stand.

Quantum theory describes a bizarre world of pure probability. Mostly, this does not work its way up to everyday reality - which is why it can go against all common sense. These probabilities interact with each other; combining, nullifying and diverging. At each time, any system exists in a constantly evolving superposition of states. Each one represents a possible outcome of an observation (in fact, the nature of these components - eigenstates - are determined by the type of question the observer is asking reality to answer). According to QM, this superposition is the reality, and these alternatives should just keep on interacting with each other. But, upon observation, all but one arbitrary survivor disappear. Why? Where do they go and what causes this privileged state of affairs? Traditionally (the Copenhagen Interpretation), this question has been answered with a brush-off - the waveform collapses and you can’t say any more about it.

Einstein did not like this - hence his famous, “God does not play dice with the universe.” The essence of his complaint is that the fundamental description of reality should not leave things unanswered. If things happen randomly then we are faced with absolutely no explanation for them; even reality itself would not know what’s going on. This is ridiculous, but I’ll leave for now just why that is.

Next up:
The Many Worlds interpretation.
Why reality has to be not just deterministic but timeless and unchanging.
How consciousness relates to reality.

I can feel your excitement….