Is the universe an enormous cellular automaton?

[bascule]

So earlier I posted a thread where I asked if any of the theories of quantum gravity presently being devised modeled the universe as a cellular automaton, and Martin's answer was no. (Actually, I think my question was about LQG. I don't think Martin was trying to say that no one had devised a theory which models the universe as a cellular automaton)

 

So, I did a little more digging and found this paper:

 

http://arxiv.org/abs/physics/9907013

 

Cellular Automata Theory and Physics: A new Paradigm for the Unification of Physics

 

Authors: Tom Ostoma, Mike Trushyk

Comments: 108 pages, 12 figures, the original Document is in MS Word format, Comments welcome, E-Mail: emqg@rogerswave.ca

Subj-class: General Physics

 

A new paradigm for the unification of physics is described. It is called Cellular Automata (CA) theory, which is the most massively parallel computer model currently known to science. We maintain that at the tiniest distance and time scales the universe is completely deterministic, and utterly simple. Our universe is a Cellular Automaton consisting of a huge array of cells capable of storing numeric information. These cells form a vast, 3D 'geometric' CA, where each cell has 26 surrounding neighboring cells that influence the state of a given cell. CA theory directly implies that all the laws of physics must result from interactions that are strictly local, therefore forbidding any form of action at a distance. CA theory suggests that space, time, matter, energy, and motion are all the same thing: the end result of information changing state in the CA. The CA model automatically contains an inherent maximum speed limit for which information can be moved from place to place.We propose that light (photon) motion is the fixed, simple shifting of a photon information pattern from cell to adjacent cell at every 'clock cycle'. Thus photons 'travel' only at one fixed speed, which is unaffected by any possible source motion. By adopting absolute CA space and time coordinates for the description of a pair of observers in inertial reference frames with a relative velocity 'v', then the Lorentz transformation follows mathematically. We explore the ramifications of this CA model for all of physics.

 

Any thoughts? I really, really like this idea... (at least what I can distill from the abstract)

[DV8 2XL]

Ya, I kind of like it too. It would be very handy if this model holds as it would make the job of large-scale simulation a lot easier.

[abskebabs]

In light of their assertions that the Universe is truly deterministic; does this also mean that the probablisitic indeterminism that we observe with principless we observe in quantum physics like the Heisenberg uncertainty principle need not apply, or at least the interpretation of these phenomenon needs to be changed?

Bascially does this mean that the indeterminism we observe is really due to a lack of knowledge or complete information of the computations that exist on this "cellular realm"? I naturally feel a little skeptical of this.

[DV8 2XL]

It stands. The relevant passage is here:

 

It can be shown that if the universe were truly random at the numeric cellular level, then a computing device would take an infinite number of operations to reproduce perfect random behavior. From CA theory, it is readily apparent that quantum wave function is not complete as a total description of the physical reality of the particle. Instead, the probabilities we measure must represent our ignorance of the exact numerical state of the CA. Furthermore, we only have information patterns available to us to probe other numeric information patterns. What we learn from this process is only how the particles interact, and from this sort of behavior we have to infer the particle’s fundamental nature.

 

The difficulty in determining the exact nature of a particle arises because we are incapable of ‘measuring’ the exact (numeric) state of a particle. To do this requires the ability to read out the numeric contents of the cells of the CA that contain the particle pattern.

Therefore in CA theory, the wave function must be incomplete as the full description of the exact state of an elementary particle. When we bear in mind that particles exist on the Cellular Automata, we can understand why Heisenberg was really correct to say (in the quote at the beginning of this section) that ‘By getting to smaller and smaller units, we do not come to fundamental units, or indivisible units, but we do come to a point where division has no meaning’.

[ecoli]

It's a nice idea in terms of theoretical physics, but I doubt there can be any real world application. There are simply too many variables in the universe to approximate a cellular automaton theory.

[pcorbett]

It's a nice idea in terms of theoretical physics, but I doubt there can be any real world application. There are simply too many variables in the universe to approximate a cellular automaton theory.

 

It's not. It's a bunch of jibberish interlaced in no meaningful way with some pop science and very rudimentary physics. And seriously, who's ever heard of a two page long abstract? Sort of defeats the purpose.

[Martin]

...and Martin's answer was no. (Actually, I think my question was about LQG...

 

if my answer was a blanket no, then I was not thinking (and definitely wrong)

 

It is not LQG (or allied non-string QG like spinfoam, triangulations path integral etc) but it is certainly out there!

 

Here is a book by Seth Lloyd that I can't recommend (or dis-recommend)---simply havent seen it

http://www.amazon.com/gp/product/1400040922/002-9614530-2726412?v=glance&n=283155

[Martin]

...and Martin's answer was no. (Actually, I think my question was about LQG...

 

if my answer was a blanket no, then I was not thinking (and definitely wrong)

 

A front-runner in this field is Seth Lloyd at MIT

 

there is a video of a seth lloyd lecture that one can download from the Perimeterinstitute.com streaming media site, so one can see his manner and get a sense of how he feels about his work at the subverbal level.

 

the field of "quantum computation" has attracted a lot of bright people in the past 5 years or so and is growing rapidly------this is not the same, but there is some cross-over

 

 

I think actually a lot of people (not only Lloyd) are interested in trying to model spacetime by a web of computer-mabob thingees

 

IF A MODEL CAN PREDICT SOMETHING THAT YOU CAN MEASURE then it is science and you can test it. It doesnt matter how fruitcake it seems. If it predicts then it is worth considering and trying out. Maybe that is an oversimplification.

 

anyway, instead of trying to react coherently, I will go get links to Seth Lloyd papers to add to your collection

 

JEEZ HE HAS REVISED THIS PAPER 7 TIMES! this is the 8th version, dated April 2006 so quite recent

 

http://arxiv.org/abs/quant-ph/0501135

A theory of quantum gravity based on quantum computation

Seth Lloyd

43 pages; 5 figures (pdf); this version with more extensive discussion of quantum cosmology

 

"This paper proposes a method of unifying quantum mechanics and gravity based on quantum computation. In this theory, fundamental processes are described in terms of pairwise interactions between quantum degrees of freedom. The geometry of space-time is a construct, derived from the underlying quantum information processing. The computation gives rise to a superposition of four-dimensional spacetimes, each of which obeys the Einstein-Regge equations. The theory makes explicit predictions for the back-reaction of the metric to computational `matter,' black-hole evaporation, holography, and quantum cosmology."

[bascule]

if my answer was a blanket no, then I was not thinking (and definitely wrong)

 

Yeah, sorry, didn't mean to mischaracterize you. I think your answer was that LQG does not model the universe as a cellular automaton.

 

And yes, you've pointed me at Seth Lloyd before, although I wasn't aware he was interested in cellular automata-based models.

 

I'll try to check out that paper...