Dan,

I just read your essay, which I found very well written. A couple of things came to mind:

1. I agree that it's optimistic to expect nature to have a bottom to its complexity. Nevertheless I, and many other people, like to speculate about what such a fundamental level might be like if there were one. I think this is OK because physics is inherently optimistic; we assume we can make some sort of sense out of the world. Once you grant yourself that, there is no limit to human ambition. However, each recent generation of scientists has made fools of themselves by assuming they were near the bottom!

2. I would hope that we as humans can modify our thinking and approaches to nature in response to what nature throws at us; in other words, I would like to think that physics is more about our ideas being modified by what we learn than about us trying to put nature into a straitjacket. Quantum theory, for instance, was mostly forced on us by observation. The human insistence that the world be commensurate with rational thought, which you view with skepticism, seems to me like a moving target, because our ideas of "rational thought" in relation to science change whenever nature hits us with something we don't expect. Of course, it's possible that humans may be incapable even of asking the important questions; we'd never expect a rabbit to be able to ask the important questions, and are we really different from a rabbit in the grand scheme of things? I think so, but my view is hardly unbiased.

Anyway, it was a great read. Take care,

Ben Dribus

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    • Post #42

    Dear Dan, i think the underlying reason for Zeilinger et al. to state the world to be quantized is not because of Shannon, but because of the underlying logics with which we neccessarily must operate in this world. You can't say X and NOT-X are true at the same time (for example X exists and at the same time does not exist).

    I gave you a positive scoring, because your essay is well elaborated, interesting to read and inspireing to me.

    All the best,

    Stefan

    5 days later

    Dan,

    You were way too low in the rankings. I just kicked you up much higher and hope that more people will see your essay and reward it.

    Edwin Eugene Klingman

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    • Post #45

    The computer and the universe

    John Archibald Wheeler

    Abstract

    The reasons are briefly recalled why (1) time cannot be a primordial category in the description of nature, but secondary, approximate and derived, and (2) the laws of physics could not have been engraved for all time upon a tablet of granite, but had to come into being by a higgledy-piggledy mechanism. It is difficult to defend the view that existence is built at bottom upon particles, fields of force or space and time. Attention is called to the "elementary quantum phenomenon" as potential building element for all that is. The task of construction of physics from such elements is compared and contrasted with the problem of constructing a computer out of "yes, no" devices.

    Preparation for publication assisted by the University of Texas Center for Theoretical Physics and by National Science Foundation Grant No. PHY78-26592.

    http://www.springerlink.com/content/ck753337h0515573/

    Dear Dan,

    If the world turns out to be Turing-computable (that is, in principle, possible to be carried out by a Turing machine), we would know there is a computer program that actually carries out exactly the same computation if our universe and no exhaustive modelling of the natural world would further be needed, unless you mean by that that the only way to account for a specific natural phenomenon is to actually run the computer simulation in order to see what happens. This would be very challenging to do so in practice as the simulation may require the same amount of resources than the universe took in order to reach that configuration (but it may also be the case that there is faster a more optimal computation).

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      • Post #47

      Somehow I doubt that "there is faster a more optimal computation" than the universe actually employs. Of course I don't really believe that the universe does actually compute anything.

      Dan

      "..the definite way that the world is can be definitely known through finite procedures." Well I think I've identified a set that can tell us a lot more at least. Sorry it took so long to get to you this year. Super essay, well written and argued. One thing took me by surprise;

      "...to determine is an act of intent." It would seem that may leave 'cause and effect' in a bit of limbo!? I just hit 'p' instead of 'o', and a 'p' appeared ('limbp'), but I did not intend to do so at all. Would 'intent' then not have to infer intelligence? But I do think you've identified an additional class or division we have missed, ignored or failed to differentiate between..

      Interestingly I think I've done the same with real and apparent (c+v) observation. I do hope you get to read my essay and like it as much as last years (I need the points!) . You certainly deserves to be higher and I'm pleased to assist. I look forward to your comments on mine; It's a full kit of parts for unification underlying a theatrical metaphor. Not long to go now for scoring. I've just bought some eye drops!

      Best wishes

      Peter

        9 days later

        If you do not understand why your rating dropped down. As I found ratings in the contest are calculated in the next way. Suppose your rating is [math]R_1 [/math] and [math]N_1 [/math] was the quantity of people which gave you ratings. Then you have [math]S_1=R_1 N_1 [/math] of points. After it anyone give you [math]dS [/math] of points so you have [math]S_2=S_1+ dS [/math] of points and [math]N_2=N_1+1 [/math] is the common quantity of the people which gave you ratings. At the same time you will have [math]S_2=R_2 N_2 [/math] of points. From here, if you want to be R2 > R1 there must be: [math]S_2/ N_2>S_1/ N_1 [/math] or [math] (S_1+ dS) / (N_1+1) >S_1/ N_1 [/math] or [math] dS >S_1/ N_1 =R_1[/math] In other words if you want to increase rating of anyone you must give him more points [math]dS [/math] then the participant`s rating [math]R_1 [/math] was at the moment you rated him. From here it is seen that in the contest are special rules for ratings. And from here there are misunderstanding of some participants what is happened with their ratings. Moreover since community ratings are hided some participants do not sure how increase ratings of others and gives them maximum 10 points. But in the case the scale from 1 to 10 of points do not work, and some essays are overestimated and some essays are drop down. In my opinion it is a bad problem with this Contest rating process. I hope the FQXI community will change the rating process.

        Sergey Fedosin

        Hi Dan, super essay, very well written and very clear. Lots of ideas I want to discuss! Not much time left here, but I have seen enough to know that you deserve a good rating, which I will certainly contribute to. Will post some comments tomorrow if I can, otherwise contact you later for more discussion. Nice job anyway. BTW, I answered the questions you posted on our thread way back when, don't know if you ever saw it, but thanks for those it was stimulating to think through them!

        Best wishes,

        David

        Hi, Ben

        I like the image you imply of physics being a game of mutual adaptation between humans and nature (the moving target). It's an opportunity for science to become self-reflective, by putting itself in an evolutionary context.

        thanks,

        Dan

        Hi, Hector

        I'm not sure what it could mean for the world to "turn out to be Turing-computable" or not. Is that mathematically decidable?

        thanks,

        Dan

        Hi, Peter

        Yes, 'intent' does imply "intelligence", or at least a projection of human agency. I believe, with Hume and Piaget, that the concept of causality involves a projection of human agency into observed interactions in nature. For myself to say that one thing causes or determines another is to "determine" that a certain relation exists between those things. Ultimately that sort of notion is based on simple human experience of making things happen--pushing objects around, including the object that is one's own body. The idea that an external object exerts the same sort of influence over another one transfers this basic idea, based on human personal agency, to impersonal objects. Just to speak of one thing causing the other leaves my participation out of the equation, which is the missing "class" you mention. My basic point is Hume's, that there is no "necessary" connection involved in the patterns of interactions of external objects that we call 'causal'. The only necessity is logical necessity. We don't seem to be satisfied that some patterns do seem to be very regular (the sun rising each day), so we invent the idea that something makes that happen.

        thanks,

        Dan

        Dan

        Hmmm. I'm not convinced cause and effect need concious 'intent'. I do however agree there's a missing interaction 'with an observers lens, that 'causes' the precise signal configuration passed on to the observers brain. That is rather different.

        The tree falling in the forest comes to mind, I've found to be in the same class as seeing the moon (in Copenhagen). If no lens is there to interact with the light reflected from it, there is no image of the moon as we know it in existence, but we CAN still see it's shadow! This is as also derived here; http://fqxi.org/community/forum/topic/1390

        Did distant galaxies interact 2bn years ago when there was no intelligent life there to see them or make them do so. As an astronomer I can tell you they did as I can see the evidence reaching us now.

        I'm pretty sure it's an unnecessary step to far to suggest they didn't! Do you disagree?

        Best wishes

        Peter

        peter

        Dan,

        Interesting essay. I agree that "the apparent "fine-tuning" of the universe might turn out to be a result of active self-organization, rather than of highly unlikely coincidence, as it is held to be in the present view of matter as passive."

        Best wishes,

        Lorraine

        Hi, Peter

        No. of course I don't disagree. My point is about two senses of 'determine'. Astronomers determine, on their best account, that certain events have taken place long ago, based on light arriving in the present era. This is literally an act of imagination, involving long chains of inference with which I may concur. This is no different from problems facing the historian--a matter of deduction from evidence--that requires the existence of a deducer. In the other sense, those events may be held to have been 'determined' by other events in the past. I simply mean that in this case too a deducer is implied. Whether the tree "really" falls in the forest, when no one is in a position to determine that is has, is epistemically an indeterminate matter. For obvious evolutionary reasons, the notion of an external reality independent of us is ingrained in the human psyche; similarly, notions about causality. We can look at these literally as truths and realities, or we can look at them as notions. I think we need to keep both ways in mind.

        thanks,

        Dan

        Dan

        I have a slightly sharper distinction. But first I agree with Mach; "It is utterly beyond our power to measure the changes of things by time. Quite the contrary, time is an abstraction at which we arrive through the changes of things."

        On reality, sure, the light we observe from billions of years ago has undergone many interactions. We would have to know all those to determine the original emitter state and position. Spectroscopy can do more than we currently realise, but is still limited, so we cannot precisely know. We also influence what we find (i.e. local c) but cannot however influence the original events. So I think we agree.

        On 'determinism' and the Copenhagen interpretation I find a simple relativistic logic. Just because nobody hears a tree fall does not mean we can't determine with good certainty that it fell. It may trip a 2km long wire, or be seen from a plane. The same with observing the moon. Just because nobody is looking at it does not mean we can't determine if it's still there or not with some accuracy. We look the other way, but still cast and see a shadow.

        I hope you'll read my essay again, as it identifies a real boundary between observer effects and effects which will exist whether or not some arrogant organism is present at any place and time in any universe. The observer, like any other condensed mass, creates local csl. read carefully a second time all the magic of 'building a new model' for the first time should emerge.

        You have to be able to visualise the evolving effects of motion, but anything you still feel 'over your head' do just ask.

        Thanks, and very best wishes

        Peter

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