Thursday, January 19, 2012

Thoughts on the universe's origin

One of the larger questions in physics or philosophy is where the universe came from. Lawrence Krauss's 'a universe from nothing' video got me thinking about it.
If we think of the universe as 4d space-time then it is just a geometry, unmoving, unchanging. We might ask why this geometry, but a starting question is, why is the time axis so different to the space axes?
Well, relativity tends to deal with how the two relate to each other, but why is there this strong dependency in the time direction?
An answer may be that the universe geometry in 4d is radial around a point, in 2d it might look like so:
The radial lines represent information, since there is a strong correlation along the length of the line, you might say that the direction of the lines (which for a small neighbourhood are roughly parallel) represents the time direction, and the other 3 directions are space directions.
Since the correlation is in this direction, it remains to decide which direction is forwards in time, this is simply the direction to higher entropy.
So I am suggesting that the time dimension is simply the one that happens to be the direction of the lines in this radial 4d shape. It explains why the universe appears to be expanding, is consistent with everywhere being equidistant from the 'big bang', and deals with why there is nothing before the big bang (because that is the centre of the volume), it is approximately the same reason that there is nothing north of the north pole, just a geometry issue with our way of parametising time.
Accelerations or decelerations of the expansion could be explained as changes in the density or roughness of these lines, effectively changing how much time is perceived to pass per unit distance along the line.

OK, so if we accept such an explanation of why we perceive a 3d universe changing through time, then the next question is: why is the universe geometry shaped like that and not some other shape?
We can't ask why there is matter in the universe, because matter is just energy (movement) which is just a correlation of information in the time and space direction. All that exists in this universe is just correlated information.
We can't ask what created this correlated information as we have removed the idea of time and cause and effect, so all we can really ask is: why is the information correlated as it is?
Which can be rephrased as: why are there these constraints on this information?

I can only consider this question speculatively... I am fairly certain that the only sensible answer is that there are ultimately no constraints on the information. In other words, each apparent constraint is an emergent constraint from the action of multiple, smaller level, less constrained information.
This idea can be seen right through physics, from Feynman's path-integral descriptions of particles, to entropic forces which explain elastic forces and probably gravity.

So at the highest resolution there are no constraints and therefore there is nothing that needs further explanation.
i.e. we are living by the high level laws that derive from infinite information acting without rules. Even logic and consistency needn't apply at the lowest levels, it is just that logic and consistency is more persistent, an invariant state or attractor of the mass of possible illogic.

1 comment:

  1. I love this idea and I think about it a lot, I think I agree with you pretty much square-on.

    What could make it all kick off? is it even meaningful to ask such a question, given the implication of time in the concept of kicking off? I think this definitely is worth thinking about, and I'm sure I'd love to discuss it with you in person one day :)

    For me what feeds into this idea is both the ideas of Wolfram (and his (and others) findings about automata, universal computation etc) and my very shallow readings from papers on a (sadly) "fringe" physics called "Process Physics" (PP).

    PP gets treated badly by the physics community, it's been deleted multiple times from wikipedia, and gets called crackpot a lot, even though it is published in journals!. It is a model of the universe as an infinite matrix of purely relational information. Nothing but neighborhood weights relating other neighborhood weights to each other. The weights participate in a neural-network-like automata in which they are updated by a function incorporating the inverse of the whole (infinite) matrix, and pure (utterly incompressible?) randomness. But lets not get stuck on details :)

    To me, the really amazing thing about PP is that it is an example where someone (Reg Cahill) claims to have been able to make a bridge between a completely abstract system that is purely semantic (ie non-symbolic, where there is no need to explain the symbols outside the system), and something that looks like the foundations of physics. PP claims to be able to see (or at least deduce) that the (nb: fractal) nodes of space, spontaneously self-organize within the system described. How he does this analysis is a bit of a mystery to me, as I lack the deepness of information-theoretical and physics knowledge required, but I do have an intuition of how this might relate to the universe (ie time) falling away from the otherwise utterly timeless constraints of computation. As you are saying, even logic and consistency needn't apply at the lowest levels, but what may still apply is what it is possible to computate (ie be in an ordering because of rules). I agree with Wolfram that this is quite distinct from the mostly-consistent formalisms of mathematics. Maths, I see as humankind's (historically important, but ultimately myopic) view of computation. Maths wilfully ignores systems that are computationally inconsistent (wolfram classes 1 and 2), and fails to really grasp the power and limitation (complexity ceiling) of computational universality (class 4, mainly).

    Indeed I find it hard to see how any previously timeless system could give rise to an ordering (of events) unless computation is at work. I mean absolutely generic computation as Wolfram describes it, lots (indeed most) of that is illogical, and inconsistent (or incomplete) in the extreme.

    I personally reject the idea of time as a dimension. I prefer to think of it as something that approximates dimensionality roughly, like a computation does. Some computations have jumps, or can be perfectly reversed. It is only when viewed from the right perspective (for example from embedded within it) that time seems dimensional. To me this also applies to space, I belive that space itself is an emergent structure within a non-spatial structure of information, and there can be other kinds of connectivity under unusual circumstances (quantum entanglement for example?)

    Please believe me when I say that I take this stuff very seriously, I'm not trying to build some newage spiritual perspective, I just love thinking about this kind of thing. So, thanks very much for your post, for stimulating me to think about it, and to try to crystallize my thoughts into words.