Essay Abstract

Since the 17th century, our conceptual framework has divided the world between what's objectively real in itself and what's only subjective, in someone's mind. This dichotomy excludes something important - the structure of the physical environment that can actually be experienced, from the viewpoint of any local system. What's significant about this internal structure is that it provides the contexts of interaction in which information is physically defined and communicated between local systems. When we describe things objectively, from no particular viewpoint, we necessarily abstract from these particular physical contexts. So theoretical descriptions of objective reality necessarily overlook the environmental structure that makes information observable. Though objective theory works well in classical physics, I doubt that this contextual structure can be ignored at a fundamental level. I suggest that physics needs to describe not only the body of context-independent fact that constitutes objective reality, but also the interaction-structure that communicates these facts as its shared information-content. Further, I suggest this two-sided view of the world is just what both relativity and quantum mechanics actually give us.

Author Bio

I have a long-standing interest in the emergence of fundamental concepts in philosophy and physics, earning a PhD in 1979 in the History of Consciousness at the University of California at Santa Cruz. The thoughts discussed in this essay grew out of reflection on Heidegger's concept of temporality in Being and Time, and its significance for physics.

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  • Post #2

Conrad

It is very complicated.

My picture more simple.

Appendix 1 Cosmological picture of one cycle

Big Bang; Present; Big Crunch

c=10^30; c=10^10; c=10^-10

G=10^22; G=10^-8; G=10^-28

h=10^-28; h=10^-28; h=10^-28

alfa =10^-3; 1/ 137; 1

e=0,1 ; e=e ; e=12

    Hi Conrad,

    I really enjoyed your essay. I agree that it's crucial to come to grips with what it means to observe the universe from the inside, and that problems arise when we try to describe the universe from an impossible God's eye view. (I've actually just written a book that makes many of the same points you made - down to the rainbow analogy!) Your idea that there is some kind of evolution of the universe taking place that reconciles the local frames of different observers is interesting - it reminds me of Wheeler's notion of the universe as a self-excited circuit. However, as I wrote about in my essay, black hole physics - and specifically horizon complementarity - has taught us that we run into trouble when we try to patch together our individual reference frames into a single "objective" world. When we do, we violate the unitarity of quantum mechanics and overcount information. The conclusion I've drawn is that we have to take as real only a single observer's light cone. It seems to me that "the" universe - a single universe containing multiple causal patches - is an impossible object.

    Thanks for a great read,

    Amanda

      Hi Amanda -- thank you! I enjoyed your essay too... it highlights a very basic philosophical issue that shows up also in Carlo Rovelli's Relational QM -- how can we imagine a universe that only exists from the standpoint of one observer at a time?

      This is a key issue not just for physics, since this is just the kind of world we all live in... that is, the only universe I'll ever see is my own. It's remarkable and convenient that we can get so far in understanding this world by assuming that each of us has a particular view of a single objective reality. But when we get to the fundamental level, I don't think it's surprising that this concept breaks down. When we imagine the world as an object, we effectively put ourselves outside of it -- and that clearly isn't how things work here.

      The alternative isn't really solipsism, though. The world I live in isn't an object, but it's not just in my head either -- it has other people in it, with their own universes. And we're connected with each other by the possibility of communication. In fact, each of us only gets to have an articulate consciousness of the world around us because we grew up in this communications environment, learning to talk with each other and to ourselves. I think something similar happens in physics - a single shared reality is constantly being "made up" through real-time communications... and the different viewpoints of local systems somehow grow out of this.

      I'll be very interested to find out more about your book.

      Thanks again - Conrad

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      • Post #5

      Hi Conrad,

      I really enjoyed the correspondence between you and Amanda. I believe Amanda's position of solipsism is at a higher intellectual level, and your position is a notch lower, but it is a much better game playing level. I believe being is the highest and best position, but I do not know anything.

      All good games involve other people, communication and evolution and progress. And as you have pointed out incorporating communication and evolution into physics will cause it to progress.

      I think of Feynman's sum over histories technique as a sort of evolution. What are your thoughts?

      I chose a much less challenging essay than yours. I went after "An Elephant in the Room". Let me know what you think.

      Thanks for bringing up the level of this contest.

      Don L.

      Interesting essay! It fits in with how I think about quantum mechanics, like e.g. that the wavefunction only (effectively) collapses according to what we measure (and to what accuracy). In my essay, I argue that such superpositions (which are entagled states with the environment), actually define the observer in a way that is more satisfactory than having to identify the observer with some "sharp" classical state.

        5 days later

        Conrad

        Brilliantly perceptive overview, showing physics is far poorer for having abandoned philosophy on alter of mathematics.

        I would think that as I've used the approach you identify to probe the mechanisms and implications of local electron viewpoints, even with some theatre in my essay to help kinematic visualisation.

        I'll just re-paste some of the important points you make close to my own, about;

        "the structure of the physical environment that can actually be experienced, from the viewpoint of any local system."

        "...need to describe the physical environment from the standpoint of a participant."

        "...the interaction-structure that communicates these facts as its shared information-content."

        (SR,QM) "...may be hard to understand because what they're describing is the world we experience, and we haven't yet learned how to think about physics from the point of view we actually have."

        "...each photon can contribute only if it's absorbed by an electron in my retina."

        "...by learning to conceptualize the world from inside, we might see more clearly what those theories are telling us."

        "...the observable world may in fact be evolving around us in real time, as we watch."

        "..we might look for vestiges of these simpler stages in the complicated physics of our present universe."

        Spot on - and what I've tried to do, and think it was successful, using the precise hierarchical 'nested' compound structure of Truth Propositional Logic, and also adapted dynamic (modal) logic to confirm the truth of your suggestion that;

        "...this kind of inter-referential structure is just what's required,"

        I hope you'll read my essay and better be able to glean the implications of the multi faceted ontological construction from the elements I describe, essentially relativistic effects derived directly from the electron detection mechanism, and with co-moving moving electrons.

        I eagerly await your comments.

        Well done. Your essay should be compulsory reading for all young physicists.

        Best wishes.

        Peter

          5 days later

          Dear Conrad,

          I just finished reading your essay. To the extent that you were able to be precise about relatively profound issues in such a short format, I think I agree with most of what you say. Let me itemize a few remarks.

          1. Regarding the information/communication-theoretic point of view, I think it's ironic that the very theories (relativity and quantum theory) whose development and application brought to light the importance and universality of such concepts continue to suffer from failing to completely incorporate their implications. For instance, if modern computer science could have pre-dated relativity and quantum theory, I have no doubt these theories would be viewed in different ways.

          2. At the end of your introduction, you state that you're not proposing any modification of GR and QM. However, as you know from looking at my essay, I believe that it's becoming increasingly clear that modifications will be necessary, and that the clues for which modifications to make come precisely from information and order-theoretic principles.

          3. Regarding the contextual nature of measurement, you know of course about Rovelli's work. The "decoherence" view of measurement is closely related by attributing "collapse" to interaction with the environment, and there are attempts to refine this view further. (See, for instance Pullin and Gambini's essay in this contest. I asked them some questions about this, but haven't heard back.) I don't feel that I understand this subject sufficiently, but I don't disagree with anything you said.

          4. In your section 3, you mention Einstein's original "vague" physical views and how his mathematical friends "reconceived them." I think that Minkowski and company may have let Einstein down to some extent, and that Riemann or possibly even Liebniz would have served him better had they been alive, since they possessed broader views and took fewer things for granted. "Lorentzian manifolds" represent a very specific (and hence limited) way of expressing Einstein's physical ideas that shackles them to a convenient mathematical formalism admitting a lot of nonphysical baggage. Just because this formalism happened to be available at the time, while information theory, category theory, etc. were not, does not mean that we should continue to be limited by it today.

          5. You mention "two geometries" in relativity, given by spacelike foliations and light cones. More generally, if we drop the manifold assumption, there are two partial orders, one a refinement of the other, and as you point out it is the causal order (defined by the light cones) that is physically meaningful.

          6. Regarding your section 4 on quantum theory, this is where things become more complicated in my view. This is because the version of quantum theory one chooses seems to matter if one discards the static background manifold. The questions of what an "observer" is and where it resides become critical. For instance, consider Feynman's sum-over-histories version (the 1948 paper). Feynman discussed summing over particle trajectories in Euclidean spacetime and thereby recovered "standard" quantum theory, with its Hilbert spaces, operator algebras, Schrodinger equation, etc. Feynman was able to take all the trajectories to be in the same spacetime because he was working with a background-dependent model; the ambient Euclidean space is unaffected by the particle moving in it. Now, if GR has taught us anything, it is that "spacetime" and "matter-energy" interact, so different particle trajectories mean different spacetimes. Hence, in a background-independent treatment, Feynman's sum over histories becomes a sum over "universes," with a different classical spacetime corresponding to each particle trajectory. His original version is a limiting case in which the effect of the particle on the spacetime is negligible. You can still make predictions in this context, but everything is tangled up with everything else; the transition amplitudes I discuss in my essay a priori depend on the entire universes involved, and it is hard to think about what an individual observer even is, except as some sort of approximation. There are also self-referential and free will issues involved. You can begin to understand why I said little about the theory of observation in my own essay, especially considering the length limitation!

          In any case, your essay rates high in my opinion. I would be grateful for any further thoughts you might have on these issues. Take care,

          Ben

            Ben,

            Thank you very much for your thoughtful response. As to your historical comments 1 and 4, I certainly agree.

            Regarding your point 2 above -- I have no doubt you're right that our current theories need to be modified. But that's beyond my level of competence; the best I can do is to recognize when some brave explorer like yourself has sound instincts about fundamental principles. But, since I do in fact propose looking at SR and QM from a fairly unusual viewpoint, I wanted to emphasize that I'm arguing only from elementary and well-established aspects of current theory, not presuming to offer a new theory of my own.

            Regarding 3 -- I don't think any of us are close to understanding "contextuality" sufficiently. Decoherence is surely relevant. As to the Gambini/Pullin essay, I agree with them that we shouldn't be assuming perfectly exact spacetime measurement, and I'm interested in their work on this. However I don't think there's anything to be gained by claiming decoherence solves the measurement problem, as their essay suggests. Most physicists already happily ignore the measurement issue without requiring any such solution in principle. I much prefer Rovelli's approach, which didn't pretend to "solve" the measurement problem but instead tried to make it the basis for a new way of thinking.

            The main point I wanted to make about measurement-contexts is (I think) new, although obvious -- namely that measuring any parameter necessarily involves measuring other parameters. To me this means we shouldn't be looking to understand measurement as a single process (e.g. decoherence, or through a theory of objective "collapse"). I think that a universe that can support any kind of observing or communicating of information must have significant structural diversity in its foundations... though we might be able to come up with an evolutionary scenario to show how this sort of functional diversity could emerge from random interaction (see below).

            5 -- I apologize for my ignorance on the subject of order theory, but could you please explain to me which partial order is a "refinement" of the other? Is it correct that refinement means adding another set of connections to an existing partial order?

            6 -- Your comment makes sense to me, and I too think of Feynman's approach as the one that takes us deepest. As to understanding what an "observer" is, at a fundamental level -- this is indeed difficult. We tend to think of observing and communicating as if they were simple data-transmission processes, ignoring the complicated contexts needed to make data meaningful and empirically definable. If it's true that many different kinds of interaction-contexts are needed to make measurement possible, then we need to ask if there could be simpler "precursors" to what we know as measurement / observation.

            For example, suppose we start with completely random interaction, imagined as an infinite randomly connected graph. As a first step toward an observable universe, we could prune off all the vertices that only connect to a single edge, since an isolated interaction can't convey definable information or contribute to a context for defining other information. Whether or not such interactions "exist" in some absolute sense, they remain "virtual" in relation to the remaining graph -- i.e. the vertices that connect other vertices, in a superposition of paths. So far there's nothing like an "individual observer" in the picture.

            The next stage might be to distinguish cylic ("self-observing"?) paths from acylic paths. (We might identify the former with all the Feynman-histories that cancel each other out, and so again remain "virtual" relative to the graph of acyclic paths.) Then the question is how to assign directions to the acyclic paths, according to internally-definable rules, that would presumably give us the causal-set structure.

            I don't have any clear notion about this, but I have vaguely in mind the way the law of charge-conservation gives us continuous connected paths, and the way charged particles "observe" each other in electromagnetic interaction. There's an intriguing inter-referential structure here relating the spatial direction of the charges' accelerations to the orthogonal E and M components of the field and to the direction of time.

            At any rate, the point is that "observing" -- what Rovelli calls "systems having information about other systems" -- may be a combination of many distinct functionalities, some very primitive, defining interaction-structures that provide a basis for the emergence of other more complicated ones. If this conjecture makes any sense, I would imagine the spacetime metric as emerging at quite a high level -- since as I pointed out in my essay, the possibility of measuring intervals in space and time appears to depend on atomic structure, hence on a lot of very finely-tuned physics.

            So maybe your "binary relation that generates the causal order" belongs to a quite primitive level of interaction, while your "overall scale factor" that provides "the measure-theoretic information" for the metric may only become definable much later on?

            In any case, I very much appreciate your reading the essay and responding so kindly.

            Conrad

            Peter -- thanks very much! I'll take a look at your essay soon. As to your initial comment, though I agree that physics badly needs a non-mathematical grounding, I'm afraid the failure lies much more with the philosophers than the physicists, over the past century.

            Best wishes -- Conrad

            Saibal -- thanks for reading and responding to the essay. I agree that identifying observers with classical states is inadequate... but the question of defining observers is complex, and I'm not sure whether an algorithmic approach is appropriate (as you suggested in your essay) -- see my note below in the thread Ben Dribus started.

            Thanks again -- Conrad

            Conrad:

            Congratulations with your essay that deals with the essantials of our "reality".

            There are a lot of paralels with "THE CONSCIOUSNESS CONNECTION" , especially the differnce between subjective and objective reality. I wonder what you think about it.

            Good luck with the contest.

            Wilhelmus

            Conrad,

            I appreciate the further explanation. Let me itemize a few more remarks.

            1. I am not satisfied with decoherence or the "Montevideo interpretation" either, but I think decoherence is better than the Copenhagen interpretation. Your initial quote from Rovelli is relevant here, though; at least part of the "problem" is surely our effort to fit the facts into a "sensible explanation" rather than taking them at face value.

            2. You're correct about the refinement of a causal relation; a good general picture of this is adding new edges to a directed graph.

            3. I agree that the metric may emerge at a staggeringly high level; I mentioned near the end of my essay that an single "elementary particle interaction" might easily involve Avogadro's number of fundamental relations. This does not bother me too much, since I believe we are very very far from the "bottom" in physics, if there is one.

            Take care,

            Ben

            6 days later

            Great Essay, Conrad. Nice work.

            I've put some comments over on my thread, where I have replied to your posting there.

            George

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            • Post #16

            Dear Conrad

            please impartially rate my essay

            http://fqxi.org/community/forum/topic/1413

            Dear Conrad Dale Johnson,

            I have not spent as much time as I would like with your essay but I have found a lot to like about it. It very clearly written and set out. There is a lot in it that I agree with. Reality and the role of the observer are things that I have also given a lot of thought. I am not sure you have said which physical assumption is wrong but you have set out some really important ideas to consider. I would like to return to it to read it more thoroughly,

            In my explanatory framework, of reality in the context of physics, there is the source of potential sensory data, the potential sensory data in environment itself and the output of processing of that data.The potential data is that pool from which an observer can select giving his unique singular output reality. The de-coherence or wave function collapse can then be viewed as the transition from considering that which exists (or might exist in the case of a single particle) as many possibilities and is still unobserved to considering the output of processing of selected data received from the environment.

            I have not written in detail about that framework in my essay as I was following the guidelines given by the organisers. However there is a diagram of it that was used to answer the essay question, and also a high resolution version in my essay thread. I think it may be something you will find interesting as I can see there is some convergence of our ideas. I would be very grateful indeed for any feedback on it or my essay.

            Good luck in the contest, Georgina : )

              Hi Georgina -- I'll take another look at your essay. I do think there's some overlap between our approaches.

              To clarify: the assumption I think is wrong is that whatever's not objectively real (describable from no point of view in particular) is therefore "subjective", mental rather than physical. But this assumption is rarely stated as such. Rather, it's built into the Cartesian/Kantian framework that still guides most of our thinking.

              In physics, this translates into the assumption that physical theory can describe the world at a fundamental level without taking the viewpoint of "the observer" into account. Of course the observer does appear both in Relativity and QM, in different ways. But because of this tacit assumption, the observer's role remains problematic, a foreign element to be eliminated from our theory, if possible. We haven't yet worked out a framework that explains how the objective view and the observer's view relate to each other, and why a fundamental theory needs to describe the world in both ways.

              My basic point is that the world is structured not only as a body of objective fact, but also as an interactive nexus that communicates those facts. That nexus is physical, not mental, and of course it's what connects objective reality with the subjective perception of an observer.

              Thanks -- Conrad

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              • Post #19

              please rate my philosophical essay

              http://fqxi.org/community/forum/topic/1413

              This is just to send my good wishes Conrad, you were one of the four people, along with Edwin, Ben and Daryl, who made the discussions really worthwhile and enjoyable for me. And I think your essay is very good. I hope we'll be in touch in the future,

              Best wishes, Jonathan

              Dear Conrad Dale Johnson,

              As discrete times that emerges from eigen-rotational quanta in Coherently-cyclic cluster-matter paradigm of universe differs, expression of unreality of time also differs in this paradigm, in that temporal ordering of events with A-series and B-series is not appropriate as block time is the discrete time in holarchy. Thus the hypersurface of the present, expressional with Minkowski space-time is not applicable in this paradigm.

              With best wishes

              Jayakar

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