Hi Markus,

Congratulations to the well-organized essay. I learned so many quantum foundations topics from this. In your quantum-optimistic hypothesis, how to deal with the data-driven science to be approached to quantum mechanics? On quantum mechanical objects or events, this seems to NOT be reproductive even by the future AI technology if this hypothesis is true.

Best wishes,

Yutaka

    Dear Markus,

    Thank you so much for writing this essay. I enjoyed reading it very much, and learned a lot of stuff. I think the message is somewhat orthogonal to my essay, but not necessarily contradictory. I like your viewpoint regarding how we implicitly assume there to be a metaphysics of things, and how this may be mistaken.

    Thanks again, and all the best,

    Gemma

      Dear Markus,

      I really enjoyed reading your essay, and I sympathize with a lot of your ideas.

      Especially, the fact that letting go of the concept of "things" and acknowledging that some questions have no answer, "dissolve" the paradoxes and avoid the invocation of weird ontological phenomena. Indeed, quantum theory invites to consider the notion of "entities" (as they were defined since Aristotle, individual objects with determinable intrinsic properties) as an "epistomological obstacle" as philosopher Gaston Bachelard might say. A metaphysical distancing from the notion of "things". While I was preparing my essay, I came across this quote from Rothstein, which I think might be in line with your "dissolution of questions" : an `` operational meaning can be assigned to question with respect to a system of interest which does not include the observer. Applied to the universe as a whole, these question lose their operational significance and become physically undecidable, they become metaphysical questions.''

      I really enjoyed your defense of an "optimistic" view. It is true that interpretations acknowledging this analysis are very often mistaken with "incomplete" knowledge (epistemic restrictions) about ontic things ; or they are straightforwardly labelled as anti-realistic, without specifying "anti-realistic towards what". Not towards the existence of an external word, but towards the notion of "things".

      I guess there might an ambiguity in your essay (or a misunderstanding from me), because I don't see QBism as "an epistemic restriction" which can be compared with Spekkens's view. I rather see it as something that might get along with your view, an optimistic position based on acknowledging that some "questions don't have answers" not because of a lack of human ability, but based on a fundamental, logical argument.

      Instead of taking a metaphysical stance as you do, arguing for an ontological realism of structures ; I tend to be sceptical towards sentences such as "the world is" (which are often related to a naïve realism (based on "things")). So I am not sure that I completely rely on your view that "the world is about structure". The word "structure" seems quite vague and ambiguous... and I prefer (for now) to strive for an "epistemological modesty" rather than designating what is ontological or not. However, you solution is way more appealing than naïve realism, since it is proposed after a careful analysis about the (un)decidability of questions. So I rather prefer your conclusion : "We can know what there is to know." Which resonate with Bohr-like sentences : "There is no quantum world. Physics is about what we can say about nature".

      If you ever find the time to read my essay, I would be glad to have your feedbacks on it. You go further than my analysis, proposing an ontological path to follow (structuralism) while I stopped at the dissolution step (for now). However, your notion of "Structural differentiation" seems rather close to my concept of "meta-contextuality", and I am very curious to have your thoughts on this.

      I hope that your essay will do great in the contest.

      Best,

      Hippolyte

        Hi Markus,

        your essay is definitely my top pick for this contest, thank you for contributing! You state in your concluding hypothesis:

        "The quantum world is probabilistic structure. In other words, it is not a "thing" or a collection of things, but it is the multitude of statistical patterns and their structural relations that any observer encounters in their data."

        So is the question here then how our discrete observational experience of a 3D world emerges from the probabilistic structure of our observations? And for you might this ontic structural - quantum - realism also be a form of wave function realism where the quantum side of that realism equates to a pure potentiality for experience rather than a thing-like external quantum world? A sort of QBist realism meets radical empiricism for which there is only the real patterns of our observational experience?

        I've long been a fan of Dennett's take on phenomenal experience (the manifest image) and its 'real patterns', or the persistent regularities of our sensory perception (cf. Husserl). Our species has evolved to perceive complex patterns in the phenomenal flux of visual, auditory, chemical, and somatic sensory experience, and where those patterns are predictive they can be considered 'real', with the natural (phenomenal) numbers being a case in point. I take it Peano's axioms would then be an account of the modern structural relations evident in the real patterns of our natural/phenomenal counting experiences, along with whatever ontological assumptions that might motivate those axioms? Such as, for some, a rather quaint (and in this case a posteriori) belief in Platonic realism for numbers.

        The ontic/conceptual structure then consists of identifying the dynamic relations between factical/real patterns--with structure defined by ontological and mathematical concepts that can explicate those patterns in terms of formalized predictions--and the history of science becomes the history of technological advances in our real pattern finding (from Kepler's telescope to the Michelson-Morley experiment and on to Aspects' entangled photons) leading to whatever necessary paradigmatic updates might be needed on the structural relations side with their subsequent technological innovations and so on... Which brings us to the contemporary conceptual mess of 21st C quantum foundations!

        In this way the structural 'laws of physics' and the ontology that informs them emerge from the real patterns observed in scientific/empirical experience. So your ontic structural realism is then an observer dependent realism? I assume this is where your 'law without law' research project begins, with a first person perspective using algorithmic probability to assign structure to sense data patterns? What is real are the patterns (the information) ... where an observer might be defined as nothing more or less than the flux of its observations situated, by simple definition, at the centre of its observable universe of real patterns and their probabilistic structural relations.

        And finally, is it this first person ontology of the observer that might provide a structural differentiation from the early modern (delusional) godlike third person perspective that reduces the observer to a simple automaton located in an unobservable classical container world of the Ding an sich?

        Apologies for crowding your thread but I find these questions fascinating and closely aligned with my own philosophical prejudices!

        All the best,

        Malcolm

        Je suis, nous sommes Wigner!

          Dear Markus,

          Your essay is one of the few that I could identify with. While I am not very sure of how close our views are it seems we agree that reality is computable. My model sort of points outs that nature is a mathematical structure that represents probability structure as in "geometric probability", also taken line-line or circle-line picking as examples. you can see that the expectation value characterizes the "process", I would guess similar to you idea. Moreover, when I interpret the line lengths(after some summing procedure and inverting and normalizing) as energy many results that agree whith QM and QFT is obtained. Also my model sort of agrees generally with

          https://www.physicsforums.com/threads/the-thermal-interpretation-of-quantum-physics.967116/

          I hope you are discouraged by my low score, since I am not into political chit chating just for the score. Thanks

            I hope you are discouraged by my low score, since I am not into political chit chating just for the score. Thanks

            of course that shout read

            I hope you are NOT discouraged by my low score, since I am not into political chit chating just for the score. Thanks

            Dear Professor Markus

            I got a very nice introduction to you from Prof. Malcolm Riddoch, this post is about furthering that discussion...

            This will give me a fundamental approach to the quantum mechanics. I will go thro' your essay soon of them and contact back to you ASAP.

            I mainly worked in cosmology , I am yet to enter into the world of Quantum Physics, i will do that in discussion with you and your friends...

            Meanwhile he asked me about my possible fundamental concepts??

            These are the Fundamental concepts of Dynamic Universe Model taken from my essay, Have a look at my essay for further details....

            C.1. Logical and Physical foundational points of Dynamic Universe Model:

            -No Isotropy

            -No Homogeneity

            -No Space-time continuum

            -Non-uniform density of matter, universe is lumpy

            -No singularities

            -No collisions between bodies

            -No blackholes

            -No warm holes

            -No Bigbang

            -No repulsion between distant Galaxies

            -Non-empty Universe

            -No imaginary or negative time axis

            -No imaginary X, Y, Z axes

            -No differential and Integral Equations mathematically

            -No General Relativity and Model does not reduce to GR on any condition

            -No Creation of matter like Bigbang or steady-state models

            -No many mini Bigbangs

            -No Missing Mass / Dark matter

            -No Dark energy

            -No Bigbang generated CMB detected

            -No Multi-verses

            C.2. Main ETHICAL foundational principles of Dynamic Universe Model:

            -Human Accrued knowledge should be free to all

            -Concept should come out from the depth of truth;

            -Authors / Scientists thinking should go towards perfection;

            -Logic should be simple

            -Theory's predictions should be verifiable experimentally, by anyone and anywhere with the same conditions

            -Computations / computer programs should be simple

            -ontological realism of senses produced information

            -New theory lead us forward into ever-widening thought and action experiments

            -Let the new theory lead us into that heaven of freedom.

            C.3. Main PHYSICAL and COSMOLOGICAL foundational principles of "N-Body problem solution: Dynamic Universe Model":

            -Natural universe regularly undergoes change in shape due to mutual Dynamical

            Gravitational forces.

            -Accelerating Expanding universe with 33% Blue shifted Galaxies

            -Newton's Gravitation law works everywhere in the same way

            -All bodies dynamically moving

            -All bodies move in dynamic Equilibrium

            -Closed universe model no light or bodies will go away from universe

            -Single Universe no baby universes

            -Time is linear as observed on earth, moving forward only

            -Independent x,y,z coordinate axes and Time axis no interdependencies between axes..

            -UGF (Universal Gravitational Force) calculated on every point-mass

            -Tensors (Linear) used for giving UNIQUE solutions for each time step

            -Uses everyday physics as achievable by engineering

            -21000 linear equations are used in an Excel sheet

            -Computerized calculations uses 16 decimal digit accuracy

            -Data mining and data warehousing techniques are used for data extraction from large amounts of data.

            Best wishes to your essay

            =snp

              Dear Mueller:

              Excellent scholarly article.

              I basically agree with your views:

              "I argue to replace this perspective by a worldview in which a structural notion of 'real patterns', not 'things' are regarded as fundamental. Instead of a limitation of what we can know, undecidability and unpredictability then become mere statements of undifferentiation of structure."

              ..... but only partly, because "undifferentiation of structure" acknowledges our persistence ignorance. In fact, that is point of my essay.

              Please, make time to read my essay and grade it.

              "Complete Information Retrieval: A Fundamental Challenge"

              https://fqxi.org/community/forum/topic/3565

              The universe is fundamentally stochastic because the observable radiations and particles are emergent oscillations/vibrations of the universal cosmic space, which is, at the same time, full of random "background" fluctuations. These fluctuations, however weak they may be, nonetheless are perturbing any and all other interactions going on in the universe. Since, human initiated measurements are also interactions between our chosen interactants in our apparatus, stochastical changes will be inevitable in every measurements, classical or quantum.

              I am an experimentalist. Aprreciating persistent & continued incompleteness in our knowledge does not require complex philosophical arguments. Our measurements will always be imprecise. That we had been, we now are, and we will always be, information limited, emerges naturally when we enumerate the basic steps in any measurement:

              (i) Data are some physical transformation taking place inside the apparatus.

              (ii) The physical transformation in a detectable material always require some energy exchange between the interactants, the "unknown" and the "known", where the "known" is the reference interactant.

              (iii) The energy exchange must be guided by some force of interaction operating between the chosen interactants.

              (iv) Since we have started with an unknown universe, from the standpoint of building physics theories, the "known" entities are known only partially, never completely. This also creates information bottleneck for the "unknown" entity. Note that in spite of innumerable experiments, we still do not know what electrons and photons really are.

              (v) All forces of interactions are distance dependent. Hence, the interactants must be placed within the range of each other's mutual influence (force-field). Force-field creates the necessary physical "entanglement" between interacting entities for the energy transfer to proceed. In other words, interactants must be "locally or regional" within their physical sphere of influence. They must be "entangled" by a perceptible physical force. Our equations are built on such hard causality.

              (vi) The final data in all instruments suffer from the lack of 100% fidelity. This is another permanent problem of imprecision. We can keep on reducing the error margin as our technology enhances; but we do not know how to completely eliminate this error.

              Many of my earlier papers have also articulated this position. They can be downloaded from:

              http://www.natureoflight.org/CP/

              You can also download the paper: "Next Frontier in Physics--Space as a Complex Tension Field"; Journal of Modern Physics, 2012, 3, 1357-1368 , http://dx.doi.org/10.4236/However, mp.2012.310173

              Sincerely,

              Chandra.

              Prof. ChandraSekhar Roychoudhuri

                Hi Markus.

                Poincare's stucturalism is found in his Science ad Hypothesis. There was a whole bunch of other related stucturalisms too, of Russell, Eddington and others, aiming to get an isomorphism between our experience of the world and the world itself. Things beyond the structure had to go, at least from the point of view of science's scope. My essay is slightly similar to yours in that it ultimately ends up pushing towards some kind of structuralism (though I don't quite call it that).

                But, given the every thing must go approach, there is a potential problem with structural underdetermination that various dualities seem to pose: these are structurally different, yet would generate what seem to be the same phenomena [e.g. AdS/CFT]. This would pose problems for your view since we then face the same question as for things: which structure is being observed? How might you deal wth this, assuming it's valid?

                (My essay is here: https://fqxi.org/community/forum/topic/3450)

                Best

                Dean

                Dear Marcus Mueller,

                Essays on top of community ranking tend to not even notice those who are ready to fundamentally justify the wave function and the redundant FT as a fundamental of it.

                I nonetheless very much enjoyed reading your anti-agnostic worldview which I share in principle. I thank you very much for reminding of Euclidean geometry which I understand as a special case of the elliptical one. Isn't use of mathematics often too less or inappropriately differentiated? To me the denial of distinction between past and future implies an unjustified arbitrary choice of the reference point which may cause confusion.

                I would like to see you on top of ranking and also on job even in case Kadin will not be quite wrong.

                Eckard Blumschein, an old Berliner

                  Dear Markus Mueller,

                  Your essay is extremely well written with sharply presented arguments. One can agree that the world which is open for opportunities (unpredictable) provides generally optimistic perspective though sometimes reality bites painfully as one can see. Questions which remain are of deeper foundational nature: why it is as it is, e.g. your hypothesis about the quantum world. It has to be originating from an underlying structure unless one accepts that every possible world exists and we just happened in this one.

                    This is a thoroughly brilliant essay. It offers, if not optimism, a palliative to even the most realistic of scientists.

                    In my essay I offer a perspective that is even more optimistic: The world is inherently spontaneous (not random and not determined), which is why we observers are inherently spontaneous, and that is why knowledge can only be tentative and limited. The world is not strange, but rather, like us, it is wonderful.

                      Dear Professor Mueller,

                      It was a pleasure reading your beautiful essay, whose overall philosophy I agree with. I fully support redefining and reinterpreting realism to make it in accord with what physical theories present us.

                      With regard to quantum mechanics, my view is that the unpredictability and indeterminism are not fundamental. Rather they emerge as apparent effects when an underlying deterministic theory is coarse-grained. I explain this in my new arXiv preprint

                      Nature does not play dice on the Planck scale

                      and also in my essay in this contest. Hope these will be of interest to you.

                      My thanks and best wishes for your success in this contest.

                      Tejinder

                        Hi Dean,

                        ah, excellent, thank you for the reference! I'll have a look at it, and will also see what Russell and Eddington had to say.

                        And thank you for your thoughtful comment on structural underdetermination! I would say that this all depends on what we exactly mean by "structure" -- a question that I haven't tried to answer in detail in my essay (I've kept it somewhat vague). In AdS/CFT, for example, depending on the answer to this question, one could either say that the boundary CFT and the bulk gravity theory are different structures, or that they are the same. It depends on what kind of notion of "equivalence" of structures we accept.

                        However, I think here we are in a better position than in the context of "things": while a "thing" is usually imagined as a kind of god-given entity with clear boundaries, we have quite a few different options to clarify what we mean by "a given structure". Hence I'm optimistic that the question of "which structure" (that you posed) could be clarified. But more work would be needed (and has probably been done by the philosophers).

                        Best,

                        Markus

                        Hi Yutaka,

                        good to hear from you, and thank you for your comment!

                        I would say that the fact that a given event cannot be predicted even by future AI (if I understand your suggestion correctly) is a good thing -- at least if you want to rely on quantum cryptography, for example. :-)

                        Of course, this doesn't mean that data-driven science or computation cannot tell us anything new about quantum mechanics. Even learning the quantum-mechanical properties of large systems seems to be something where such science, and perhaps AI, can be immensely useful

                        All the best,

                        Markus

                        Dear Gemma,

                        thanks so much for your kind words! I'm glad you enjoyed the essay.

                        I believe that our views are not really orthogonal, they are just emphasizing different aspects. I fully agree that "undecidability is everywhere". Whether we see this as a limitation (for example, we cannot predict all aspects of some system) or as a positive outlook (differentiation is everywhere) may be a matter of perspective.

                        Hope to discuss this in person once the crisis is over!

                        Best,

                        Markus

                        Dear Hippolyte,

                        thanks so much for your kind words, and for your detailed comments!

                        I agree that there is a big difference between Spekkens' view and QBism. Seeing the quantum state as some kind of incomplete knowledge is very different from seeing it as an agent's belief, and there are many more differences between these views. Still, I think that they have something in common: they see the quantum state as something that pertains to some notion of observer which is seen as holding incomplete information in some sense. Hence, both views express the hope that more can be said about the part that is not known to the agent that assigns the quantum state, presumably about some underlying reality: either by finding a kind of plausible "causal" ontological model, or by understanding what the Born rule has to say about the world on which we place bets.

                        I also agree that the word "structure" is ambiguous. I guess there are two reasons for it: first, this is only an essay, and I didn't do the hard work to make this notion mathematically or philosophically sound or fully concrete (the structural realists among the philosophers have more to say about this). Second, however, it must *seem* vague to some extent: after all, what we would intuitively label as our most "concrete" understanding is naturally in terms of *things* -- and this is a view that is explicitly rejected here.

                        I will try to have a closer look at your essay, the abstract sounds very interesting!

                        Best,

                        Markus

                        Dear Malcolm,

                        thanks a lot for the thoughtful and fun comments! I'm glad you liked my essay.

                        You write: "And for you might this ontic structural - quantum - realism also be a form of wave function realism where the quantum side of that realism equates to a pure potentiality for experience rather than a thing-like external quantum world?" Yes in fact! I'm stunned that you managed to formulate what I mean so clearly, even clearer than I did myself in the essay!

                        Regarding Dennett's real patterns, I'm a big fan of this (and referencing it myself), but I think there is a hidden subtlety that is related to other issues like Goodman's New Riddle of Induction. To say what a pattern is, you have to choose a compression algorithm, or a universal machine (which is analogous to a choice of language). For finite data, the notion of compressibility will depend on this choice. Any ultimate definition of a real pattern will have to deal with this issue in some sense...

                        I really like this paragraph of yours:

                        "... and the history of science becomes the history of technological advances in our real pattern finding (from Kepler's telescope to the Michelson-Morley experiment and on to Aspects' entangled photons) leading to whatever necessary paradigmatic updates might be needed on the structural relations side with their subsequent technological innovations and so on... Which brings us to the contemporary conceptual mess of 21st C quantum foundations!"

                        :-)

                        Very well described!

                        Just a final comment on this question of yours:

                        "I assume this is where your 'law without law' research project begins, with a first person perspective using algorithmic probability to assign structure to sense data patterns?"

                        Even though algorithmic probability is used in this approach, the idea is somewhat different. In some sense, it starts with a form of methodological solipsism: there is your state S now (intuitively, containing your sense data and memory), and you will be in another state T next. In that approach, what that next state will be doesn't depend an any "external world" (as we would usually think), but only on algorithmic probability P(T | S). Why such an approach? Well, suppose we are interested in "observer paradoxes" like Parfit's teletransportation paradox (or others, e.g. simulating observers on a computer), and we claim that there is an objective chance of what such an observer will see in those situations. Then the answer, almost by definition, cannot be grounded on properties of the external world (even if there is one).

                        Surprisingly, one can show that, if we assume such law, then things look in the long run, for any observer, pretty much *as if there was* an external world. So the notion of "world" is emergent there, and an abstract notion of "self" is fundamental.

                        In case you're really interested, there's a link to an online talk on my homepage (mpmueller.net). But enough of advertisement.

                        I'll try to have a look at your essay. I'm curious now!

                        Thanks again, and all the best,

                        Markus

                        Dear Chandra,

                        thank you for your comments!

                        Let me ask a clarification question. When you point out that we are "information limited", are you then saying that this will forever prevent us from getting any "final answers" about reality? In the abstract of your essay, you seem to argue the other way: that we can make progress nonetheless.

                        You also write: "Unlike Copenhagen Interpretation, we do not need to give up visualizing ontological reality." So are you claiming that there is an underlying reality in the usual hidden-variable sense, and that we can get our hands on it?

                        Best regards,

                        Markus

                        Dear Eckard Blumschein,

                        thank you for your comment! Honestly, I don't quite know what to make of it... but I thought I'd send you best wishes to Berlin, where I've lived for several years.

                        Best,

                        Markus