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Simpler Anthropic Principle: the Computeric Principle

  1. Oct 16, 2011 #1
    I just read the Spacetime article on wikipedia which argues that the spatial and temporal dimensions (N=3, T=1) are special, since without them no life as we know it could ever exist.
    It is not clear to me however if a computer (or better an (in)finite Universal Turing Machine) could ever exist at dimension different than (3, 1).
    Is it the case?

    Also, I prefer to use a Computeric Principle rather than an anthropic one, given that defining "life" is rather difficult, and yet more defining "intelligent life". Will using a Computeric Principle present problems or would it be just better?

    I am looking forward to read your thoughts.

  2. jcsd
  3. Oct 16, 2011 #2


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    This seems kind of tautological. They list all sorts of reasons why, if our universe had <>3 spatial dimensions, it would be very different from our own.

    Last edited: Oct 16, 2011
  4. Oct 16, 2011 #3


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    I actually have a design for how life can work in only 2 dimensions. :biggrin:
  5. Oct 16, 2011 #4


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    Here's my thought.
    Should it not be degrees of freedom rather than dimensions.
    Spacially we can move up-down, left-right, forward-backward. Temporally, we have only one direction - forward. And, also there is the spinning about an axis, which adds another 3 degrees of freedom.
  6. Oct 16, 2011 #5
    A few points:

    1. The anthropic principle is, of course, essentially tautologous. However it does help to draw attention to the apparent fine-tuning and observed directionality of the life process and to try to find explanations for these very pervasive and persistent patterns.

    2. The two dimensional model is amusing. However, we must remember that there is no empirical evidence for two dimensional entities in the physical (real) world. All our representations being approximations. (No problem within mathematics, though, where any number of dimensions are allowable)

    3. Yes, a computerthropic principle is equally valid, although subject to the same limitations.
    Last edited by a moderator: Aug 29, 2012
  7. Oct 17, 2011 #6
    You read me wrong. What I am saying with the Computerthropic principle is a precise mathematical statement (right now just a conjecture):

    Consider the laws of physics L, parametrized by space and time dimensions and other parameters such as mass,charge,spin of elementary particles, etc...: L(SpaceDims,TimeDims,electron-mass,Gconstant,...).
    In L(3,1,m_e,G,..) we clearly are observing and it is actually possible to prove that implementations of (in)finite Universal Turing Machines are possible.

    Question/Conjecture: for any (S,T,E,G,...) != (3,1,m_e,G,...), then in the universe L(S,T,E,G,...) it is not possible to implement an UTM.
    Expressing the above question in another form:
    Code (Text):

         let P(S,T,E,G,...) be the sentence:
             P(S,T,E,G,...) = "In L(S,T,E,G,...) it is possible to "implement" an UTM."
         then, (3,1,m_e,G,...) is the unique solution to the equation
             P(S,T,E,G,...) = True
    (I should define "implement", but for now, let me just skip this)

    Now, I am not saying that in any "universe" of (N,T) dimensions it is not possible to implement an UTM. For example, 2d Cellular Automatons are Turing-complete, thus, they admit such a thing. What I am interested in is not just "any universe", it is "our universe", as defined by the current laws of physics (Quantum Mechanics, Relativity, Standard Model of elementary particles, etc...).

    The above "Computerthropic principle" isn't affected by tautologic reasoning: axioms are "Laws of Physics L", question is "for what parameters I can actually build a computer inside a universe with laws L?"

    Thanks for the reference, I skimmed through it (just to page 8 right now) and I find myself in line with your main ideas. I also believe that the birth of a singularity could be a very good thing for human beings. My favorite analogy is: we would become like domestic animals in a beautiful giant garden, we would be treated and spoiled to death (and perhaps we'll never be able to notice it).
    Last edited: Oct 17, 2011
  8. Oct 17, 2011 #7
    However, while your basic conjecture/question is interesting and seems sound, it seems to me that as soon as you tie it to "our" universe with its observed dimensions and parameters and for which implementation of an UTM is known to be possible then tautology arises? Perhaps I am still missing something here? I will be interested to hear what others have to say.
    Last edited by a moderator: Aug 29, 2012
  9. Oct 18, 2011 #8
    Unfortunately I am not "others", but here it is my answer: your observation just implies that in L(3,1,...) such a thing is possible, i.e. you can build an UTM in it. That's it. Nothing more. Perhaps in L(51,2,...) it is not possible, perhaps it is.

    Perhaps the following remark is due: when I say "your observation just implies..", I mean "IF our universe really is described by the set of laws in L, and has parameters (3,1,...), THEN your observation just implies.."
    However, apart from the above IF, the mathematical question "is L(N,T,a,b,c,..) able to contain an UTM?" is well founded.
    Last edited: Oct 18, 2011
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