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    Wheeler’s Utterly Simple Idea That Demands The Quantum
    By Sascha Vongehr | September 3rd 2012 07:58 PM | 54 comments | Print | E-mail | Track Comments
    About Sascha

    Dr. Sascha Vongehr [风洒沙] studied phil/math/chem/phys in Germany, obtained a BSc in theoretical physics (electro-mag) & MSc (stringtheory)...

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    The physicist John Archibald Wheeler wrote in 1984:

    ...the most revolutionary discovery in science is yet to come! And come, not by questioning the quantum, but by uncovering that utterly simple idea that demands the quantum.” Wheeler, 1984 [1]

    Here is where a “modal realist version of Einstein”, while contemplating the Einstein-Podolsky-Rosen paradox involving the infamous Alice and Bob characters, could have stumbled onto Wheeler’s “utterly simple idea that demands the quantum”:


    “What matches up the many different Bobs with the possible Alices (all observe only one Bob and one Alice) so that ‘reasonable’ stochastic laws emerge from this chaotic mess? A physicist naturally asks for the ‘mechanism’ that has access to the alternatives to accomplish that ‘interaction’ between them.  That ‘interaction’ is precisely what QM with its superposition and entanglement and interference between possibilities is, and its necessity demands the quantum.” [2]

    The fourth FQXi contestWhich of Our Basic Physical Assumptions Are Wrong? is now closed. My entry [2] argues that physical actualization of future is the worst offender, and that without it, many profound difficulties will become as trivial as the earth orbiting the sun (no big claim here - it always works out this way with paradigm changes, and who wants to claim that quantum mechnics will not lead to a true paradigm change).


    Everett Relativity follows from Special Relativity added to the indeterminism of tautological modal realism. Source: [2]

    First request I ask of you today: Go read it please, but be warned. It is the most difficult piece I have ever written. I struggled hard and had to reject some of my own terminology, improving it considerably during these months. The essay changed much since the drafts you may have seen; there is sweat and blood in every line. Many people helped me with making it as clear as possible (thank you Gerhard, Richard, and many more who may not like to be mentioned by name), but because the content cannot be put very differently without destroying the message, it stays to be a difficult read. It can be understood with some effort, as it is self-contained (except for the appendix), and color coding definitions of terms (green) and numbering paragraphs (blue) with extensive cross-references are there to help. I promise that it is worth your effort.

    It has to be read twice in order to see that most sentences (which should themselves often be read several times), however strange or clumsy some of them seem, can hardly be put any other way without becoming wrong and/or conflicting with the whole. There is no other way to anticipate a paradigm (the language of which) we do not know (certainly not given a 25k character limit). There is no other way to address the fundamentally wrong, as the contest explicitly asks to do (!), i.e. the meaningless, without violating the main lessons that Wittgenstein taught us, namely, that one has to be silent about the meaningless.


    John A. Wheeler

    Because of the unavoidable level of difficulty, here the second request I ask of you: Write me here in the comments (or email me) your criticisms and questions. I will put together a FAQ or even write articles about particular issues (probably things like whether I do or do not “believe” in “many-worlds” and suchlike, but maybe there are some surprise topics). Ideally, I would write an article about every single one of the 24 small paragraphs, but time is money.

    “An interaction faster than the fastest possible in the isolated game is a sure sign of players messing with the game pieces.  As Einstein said: spooky!  Whether it be gods or alternative worlds, there is interference.” [2]

    Third request: The title here is “Wheelers utterly simple idea”, but the title of the essay is “Realism escaping Wittgenstein’s Silence: The Paradigm Shift that renders Quantum Mechanics Natural”. Since the essay is difficult, I can hardly title it via “utterly simple”, but tell me whether you can agree with what the essay implicitly claims, namely having isolated (at least partially or one version of putting) Wheelers ‘simple idea’, and whether I am correct in that it is “utterly simple” if only expressed in the natural language of the future’s modal realistic paradigm.


    No fourth request: I am not asking you to not vote for it, but I do not ask you to vote for it. I dislike this creepy exploitation of crowd dynamics and wooing for popularity that everything, even “science”, developed into. I do not desire your vote; I want you to understand it, because if you do, you will realize that the deepest current issues in physics and philosophy will be as trivial as the earth circling the sun and self-evident to school children in the future. This implies in turn that you can help to make it so! The essay, basic special relativity, the Quantum Randi Challenge, the EPR resolution, all can and should be, and with your help may be soon, made into a picture book that ten year olds will enjoy and into movies that people will want to watch.


    --------------------------------

    [1] J.A. Wheeler: “Bits, Quanta and Meaning” in Theoretical Physics Meeting: Commemorative Volume on the Occasion of Eduardo Caianiello's Sixtieth Birthday, A. Giovanni et al. eds. (Edizioni Scientifici Italiani, Naples) 121-134, 1984


    [2] S. Vongehr: “Realism escaping Wittgenstein’s Silence: The Paradigm Shift that renders Quantum Mechanics Natural”. 4th FQXi Essay Contest http://fqxi.org/community/forum/topic/1483 (2012)

    Comments

    Hi,
    I for once agree with you. However, one thing is to say QM and many worlds arise from modal realism and relativity and a different one is giving a precise mathematical framework deriving it. If your idea is as promising as it looks, you should give that a go. I'd love to read the paper once it was ready. What I fail to see is exactly how interference arises in your picture: it is easy for me to understand how the many world arise, but I don't see how you can rigorously derive interference from your assumptions. I understand it comes at the intersection between different past light-cones, but I would need some more detail on how it is actually done.

    vongehr
    "a different one is giving a precise mathematical framework deriving it. If your idea is as promising as it looks, you should give that a go."
    I agree; having the 'simple idea', say Einstein's elevator thought experiment (in a sense the core of general relativity), is very different from working out the mathematics of the theory, which needs many clever people (like Riemann, Minkowski, Schwarzschild ...). With relativity, the maths came mostly after the simple idea (application of Riemann geometry to physics I mean for example, not the appearance of it inside mathematics). The maths of QM is pretty far developed already. On the other hand, we likely need to unify with gravity to have something satisfactory. So the questions are: What would I need to work out, is there something left to work out about this idea at all, is most of the QM math still to come, perhaps via the 'simple idea'? I have no idea about that! What to do? Perhaps something similar to what David Deutsch is doing? EPR in curved space time? Different persons have different strengths and interests. There are many people who are better than I am with those issues.
    Amir D. Aczel
    Fascinating!
    Amir D. Aczel
    vongehr
    Complete nonsense can be fascinating. The question is: Do you agree, and if not, where is the problem?
    vongehr
    Most comments on FQXi are Joy's fan boys trying to get back at me for revealing him as the crook he is (thankfully, most have been deleted by FQXi moderators). Of course, the public rating is thus already lost - hail the internet, oh gutter of the mob. However, next to off-topic anti-Einstein pseudoscience, there is finally one serious comment, so let me present it here:

    Armin Nikkhah Shirazi wrote:

    Dear Professor Vongehr,

    I read your essay but must admit it was not an easy read.

    The overall picture I get about your description of tautological modal realism is that we would expect the most fundamental theory of nature to describe it in its totality, and that this implies articulating all possible alternatives into which the parts of nature can evolve to in the next instant, and furthermore, that these alternatives are treated equivalently with respect to such a theory, and finally, that because there is nothing else to compare the totality to, it can only be compared to itself, and hence its description becomes tautological.

    Your argument then would be that since QM already contains some of these features it may be close to, or perhaps even already be, our most fundamental description of nature. So for someone who has adopted the tautological modal realism perspective, Quantum mechanics should appear natural, if not even tautological, and the assumption that QM is "strange" is wrong.

    Although I find your argument quite ingenious, I seriously doubt that many people will be convinced by it to regard QM as "natural" (unless, by virtue of becoming so familiar with the theory, it no longer triggers their sense of wonder).

    The reason why I doubt this is simple: Surely someone before QM was developed should have developed intuitions in line with tautological modal realism, and been filled with puzzlement that measurements on objects up until then yielded definite results (within the accuracy and precision then available), and they would have been disturbed about the absence of observable superposition. I would be amazed if such a person existed. Moreover, from what little I understand about tautological modal realism (if I even understood it at all) I don't see why it should not lead us to expect to observe macroscopic superposition phenomena (not necessarily due to quantum mechanics)? Should it not lead us to expect to observe superpositions of gravity fields at energy scales which are accessible to us, for example? If we adopt this worldview, then, it seems to me, it would be inconsistent that we emphasize how well it fits one set of our observations but not emphasize how poorly it fits another.

    I'd like to emphasize that I am not suggesting in any manner that QM is wrong or not a fundamental description of nature. My point is, rather, that adopting this type of worldview post hoc seems to me akin to a form of rationalization.


    I accept that quantum mechanics is correct and fundamental, but that does not stop me from trying to understand what the origin of its puzzling features is. Some of my professors have told me that "why" questions are not the kind with which physicists are really concerned, but I strongly disagree. We have to keep asking "why" if we want to maintain any hope of gaining deeper insights into nature. Adopting a worldview which keeps me from asking "why" seems counterproductive. Indeed, it was because I kept asking why that I believe I made any progress in my own attempts at trying to 'understand' quantum mechanics.

    The previous commenters have painted a picture of someone who does not take criticism well, but, not having had any prior interactions with you, I like to believe that when faced with an attempt at respectful, thoughtful and constructive criticism, you will receive it in the spirit in which it was given, namely that we can benefit and learn from an exchange of each other's perspectives, even if they sometimes disagree.

    All the best,

    Armin
    vongehr
    Thank you for your on topic comment. Do not be confused by certain other commenters - I have once outed a pseudo-scientist who cheated his way through academia and his friends are trying to get back at me - welcome to the internet. As I said above, especially on my science column, serious commenters are taken very seriously. To your comments:
    we would expect the most fundamental theory of nature to describe it in its totality
    This is not about us expecting, but it being so by definition ("most fundamental"). Expectation is to do with empirical input, but a tautology is true regardless in which universe you happen to find yourself in (QM is where all possible universes "come from").
    Your argument then would be that since QM already contains some of these features
    No, statistical mechanics already does (all configurations in phase space).
    Although I find your argument quite ingenious, I seriously doubt that many people will be convinced by it to regard QM as "natural"
    This is because you left out most of the argument. One of the main points is that tautological modal realism is NOT yet QM. You need to add special relativity in order to then come to Wheeler's "utterly simple idea that demands the quantum". Before that, many worlds are not QM. (Please see this once more explained in the new article: Indeterminism comes before QM)
    Surely someone before QM was developed should have developed intuitions in line with tautological modal realism
    Precisely! For thousands of years there have been people for who "possibilism" was self-evident.
    would have been disturbed about the absence of observable superposition.
    No - superposition needs QM! The latter comes natural after special relativity is properly understood. Tautological modal realism is just as tautological in a world where there would be classical probabilities (that do not violate the Bell inequality).
    I accept that quantum mechanics is correct and fundamental
    I do not exclude 'further facts' like Bell's fifth position or gravity induced non-linearities (e.g. Diosi-Penrose).
    We have to keep asking "why" if we want to maintain any hope of gaining deeper insights into nature.
    The question now is, for example, why do the correlations between alternative worlds lead to Born probabilities rather than stronger or less severe violations of the Bell inequality. This will likely be answered via David Deutsch's ideas hitting Relational Quantum Mechanics as applied to EPR.

    Thank you again for your comment.

    Sascha
    The question now is, for example, why do the correlations between alternative worlds lead to Born probabilities rather than stronger or less severe violations of the Bell inequality. This will likely be answered via David Deutsch's ideas hitting Relational Quantum Mechanics as applied to EPR.
    This is something (else) I do not understand. The Born probabilities are a natural way of extracting the amplitude of an eigenfunction from a superposition. It can hardly be a coincidence that the formula works. My maths is too rusty for me to develop this theme but I'm sure yours isn't. 

    This is what I have in mind:

    If a state comprises an "ensemble" of possible (in the sense that we lack information) observer-microstates each with a superposition of possible (in the sense of not actualized) observations then, after the observation has been made, one has

    a) An ensemble of actualized collapsed wavefunctions according to traditional Copenhagen stories
    or
    b) An ensemble of |observer-observation> superpositions according to the Schrodinger equation.
     
    The superposition rapidly decoheres and creates the Born probabilities.  This is quite well understood and there is no mysterious "observation" process causing wave function collapse, there is just an ensemble of superpositions of different |observer-observation> worlds.

    What I don't understand is how this known, deterministic, evolution leaves any room for "stronger or less severe violations of the Bell inequality". What am I missing?


    _
    vongehr
    I should not have mentioned the name Born here. You are probably correct in that once I already assume that math, the result is the one we know (though don't tell a mathematician or so, because they almost always find a way out if they want). However, in the context of the essay (and also the
    Quantum Randi Challenge), we want to assume almost nothing but still derive that QM is non-classical, meaning it violates the Bell inequality. That would be the case already if the inequality is violated just a little, like if I start tuning the number of "extra branchings" in my EPR many-world toy models slowly from classical towards the full sin2(delta). What I meant here is that via some sort of, now still heuristical argument (partially given in the new version of the Quantum Randi Challenge paper on the archive and also in the new "sunglasses article"), we arrive at the sin2(delta) and perhaps can even go further and say that only the Born-mathematics can model this (which would be the part that I would try adapting from David Deutsch).

    Well that isn't going to happen is it? There is a trivial counter-example: namely the "totality" of Shakespeare's Hamlet where despite a great deal of "spooky action" and indeed, "interference" between "worlds", there is nothing resembling Bell inequality violation! :)

    I'm not sure whether you have enough fire-power to achieve your objective. A class of theories can be created in which, a priori, worlds split apart and cease to interfere (Everett Many Worlds) or cease to exist altogether. How would this class be ruled out tautologically? - implying that such a totality is not merely factually incorrect but self-contradictory. All you have to work with is a definition of "fundamental" that makes all possibilities equivalent: where is interference actually forced upon us? Why *must* worlds interfere? Well, okay, you haven't got there yet, so I'm being a little unfair. And I need to re-read your essay - with a microscope.

    vongehr
    There is a trivial counter-example: namely the "totality" of Shakespeare's Hamlet where despite a great deal of "spooky action"
    Since when has Shakespeare special relativity inside? Everett relativity comes from Einstein relativity in my essay.
    I disagree with you.
    In some ways I agree; and in other places perhaps I don't understand.

    My disagreement with you begins with "tautological modal realism". "Tautological modal realism belongs to the fundamental theory of totality by definition." I disagree. or just agree in a trivial sense.

    "Modal realism is the view, notably propounded by David Kellogg Lewis, that all possible worlds are as real as the actual world... The term goes back to Leibniz's theory of possible worlds, used to analyse necessity, possibility, and similar modal notions. In short: the actual world is regarded as merely one among an infinite set of logically possible worlds, some "nearer" to the actual world and some more remote." wiki

    "universal limits of language limit the universe." But here I agree.

    Let me quote from Heisenberg book Encounters with Einstein.
    "In relativity the old concept of "simultaneity" had to be sacrificed.. in quantum mechanics the notion of electron "pathway" (had to be sacrificed).. in particle physics the concept of "division" or of "consisting of" has to be given up." pg 54 lecture May 26, 1975
    ""dividing" and "consisting of" have a limited range of applicability. Just as in relativity the concept "simultaneous" or in quantum theory the concept "position" and "velocity" can be applied only with characteristic restrictiveness, and lose their meaning when used uncritically." pg 58-59 lecture Aug 18, 1975
    "Neither the word "orbit" nor the word "moving" are well defined.. hence the question has no meaning." pg65 lecture Aug 18, 1975
    "certain mistaken developments (in physics).. are due to the fact that authors do not wish to trouble about philisophy but.. in reality they unconsciously start out from a bad philosophy." pg 71 lecture Mar 5, 1975
    "only with the help of the correct concept can we really know what has been observed." pg 19 lecture Sept 18-25, 1972

    So In my mind the " utterly simple idea that demands the quantum.” Wheeler, 1984 had been explained by Heisenberg in 1975.
    The classical ideas of "pathway", "momentum" and "velocity" had to be seriously limited in order to "correctly" explain "what had been observed".

    Heisenberg "For an understanding of the phenomenon, the first condition is the introduction of adequate concepts; only with the help of the correct concept can we really know what has been observed. When we enter a new field, very often new concepts are needed, and these new concepts usually come up in a rather unclear and undeveloped form. Later they are modified, sometimes they are almost completely abandoned and replaced by better concepts which then, finally, are clear and well-defined. " pg 19 lecture Sept 18-25, 1972

    what is the source of Wheller's 1984 quote. Without reading the quote in context, I assume based on my reading of Heisenberg; that Wheeler was looking for something "utterly simple idea that demands the quantum" in the sense that general relativity is an "utterly simple idea that demands the gravity."

    So, I think you have misunderstood Wheeler's meaning.
    And string theory may yet be an "utterly simple idea that demands the quantum and general relativity"; but "we have enter a new field, new concepts are needed, and these new concepts have so far come up in rather unclear and undeveloped form. If string theory proves correct; then we will know what concepts need to be modified, which almost completely abandoned and replaced by better concepts; and only then will we finally have clear and well-defined new concepts."

    In my mind, yes, "direct reality" had to be replaced by "indirect or "representational" realism" (which also has its problems. but "modal realism" not yet clearly defined. But I would suggest that our definition of "realism" is just bad philosophy trying to lead to good physics; it can't.

    For sure special relativity, general relativity, quantum mechanics, etc. suffered from mistaken ideas of "realism". But it was not a clearer concept of "realism" that lead to special relativity; it was a clearer idea of "simultenaeity". Similarly, a clearer idea of "equivalence between inertial and gravitational mass" lead to general relativity. And a clearer idea of "momentum" and "velocity" lead to quantum mechanics. Yes our idea of "realism" then changed; but not necessarity in the direction that philosophy a priori would have suggested.

    Now back to you, ""Tautological modal realism belongs to the fundamental theory of totality by definition."
    "The universe belongs to the fundamental theory of totality by definition."
    "Consciousness belongs to the fundamental theory of totality by definition."

    But I suggest that "concept" that needs clearing up in order to take a next step forward in physics is not "tautological modal realism", "the universe" or "consciousness"; the concept that needs to be cleared up is something more mundane like "simultaneity" or "path" or "division".

    So I disagree with you; despite agree that there is something both metaphorically correct and factually correct about the idea of "modal realism." The problem with the idea of "modal realism" is that, the idea and term goes back to Leibniz's (1646-1716) theory of possible worlds. But Leibniz's philosophy did not play a significant role in the developement of 20th century physics (either in foresight or hindsight).

    Of course in all of this, I have not even focus on definitions of "the world", "the universe", "the totality"; clearly such concepts are ill defined, fuzzy at best, full of philosophical speculation; if for no other reason that there are so many unsolved problems of physics http://en.wikipedia.org/wiki/Unsolved_problems_in_physics, methematics, psychology, biology, chemistry, philosophy, etc....

    vongehr
    My disagreement with you begins with "tautological modal realism". "Tautological modal realism belongs to the fundamental theory of totality by definition." I disagree. or just agree in a trivial sense. "Modal realism is the view ...
    Item (6) in the paper: "I define “tautological modal realism” as the acceptance of fundamental equivalence (4, 5) combined with labeling possibilities “real”, be they worlds or not."
    (If an author defines y := 2x, you may argue about that his conclusions about y are wrong, say if x = 1 and the author claims y = 7, but you cannot say that y is something else and then claim that the author is wrong because y = 2 does not fit your own definition. The author defined y to be 2x, period.)
    utterly simple idea that demands the quantum.” Wheeler, 1984 had been explained by Heisenberg in 1975.
    If that were the case, everybody would know by now! Wheeler demanded an utterly simple idea, something like the elevator thought experiment supporting the equivalence principle.
    "utterly simple idea that demands the quantum" in the sense that general relativity is an "utterly simple idea that demands the gravity."
    This is either nonsense (sorry, but general relativity is "utterly simple"??? - if Wheeler actually meant that, it would be nonsense just the same) or you mean precisely what I say in item (10) of the paper.
    "modal realism" not yet clearly defined.
    Item (6) in the paper:"(Empirical) “modal realism” usually labels possibilities “real” especially because QM has shown them to be necessary (8, 13) in the explaining of observed phenomena." It is thus clearly defined in the paper as adding certain empirical facts (e.g. Bell violation, superposition) to tautological modal realism, which was very clearly defined just before. Other authors not clearly defining "modal realism" is a different issue.
    I think you should read the paper once more after giving attention to the introduction. This is about the fundamental description. To take definitions seriously is a very important aspect, the most important one actually.
    Sasch
    Thanks for responding. However your response is less clear to me than your essay. Which I have read and reread the entire essay several times while searching google and wiki to understand meaning of various phrases.

    It still reads as interesting but bad philosophy trying to better explain physics.

    Yes, I can and do explain to my 5 year old that direct realism is incorrect. I don't use the phrase "direct realism"; but I assume that he can understand ANYTHING.

    So if you think your "essay... (can be) made into a picture book that ten year olds will enjoy"; then please give me the BIG PICTURE STORY in less than 100 or 500 words. Maybe then I will get it. Until then, your essay is bad philosophy and no new science; but interesting. I must still disagree as I explained above.

    "Many worlds" much beyond "a bugs world is different than mine; my world is different than yours"; is philosophical mumble jumble unless you get specific. It doesn't lead to relativity or quantum mechanics. Rather relativity and quantum mechanics lead to a clearer idea of what we might mean by "many worlds."

    I await a BIG PICTURE STORY of your essay.

    vongehr
    The terms are all defined as I defined them, even "many worlds"; there is no point to go google anything. If you refuse to accept an author's definitions, of course you cannot understand the text that is based on those definitions. Of course it does not lead to QM if you use some googled "modal realism" instead of "tautological modal realism" as I defined it! As I wrote to you already, you need to understand the importance of terminology and definitions. Without that, there isn't any point in communicating, as one simply talks past one another. If you do not want to respect the definitions of the author, there is simply no further communication possible, just like you can't communicate with a Chinese speaker if you insist on half the words being Russian.
    The picture book stuff is about the many world toy models. I won't explain it in 500 words, because a picture is a thousand words as they say.
    So, without trying to be rude, it is simply a fact about meaningfulness that if you don't care about my definitions, there is no point in communicating. We communicate on the basis of my definitions about that essay or perhaps we can communicate about the suitability of certain definitions. There is a reason that I spend a whole page of my mere 10 page limit on Wittgenstein and his insights about language.
    I Google because I do not understand or cannot find your definitions. It is not a matter of disrespect. It is a matter of trying but not understanding what you are saying.

    Even now, as I go through your essay I cannot find your definition of "many worlds". For sure you use the term but I see no clear definition.

    As for the meaning of "modal realism" versus "tautological modal realism"; I also see no definition of "tautological modal realism." And if I Google "tautological local realism" I find pages and pages of links that lead to one thing only: Your essay. So well done you've defined something that apparently no one else has.

    But my basic point (over and above my other points, since you insist that I have not listened to you) is this: You have not listened to me; your essay is unintelligible to me. I have tried because I do respect you and have read several things that you have written before.

    My comjment about asking for a BIUG PICTURE STORY was because you suggested that your idea should be understood in a story to children. But the fact that you refuse to accept is that you have not communicated you idea clearly enough for me to understand. I have really tried to understand.

    So I can explain in child language to a ten year old:
    -General or special relativity
    - quantum mechanics,
    -string theory
    -quantum field theory

    But I can not explain to myself (or a 10 year old) "tautological modal realism".
    Usually, when I go to arXiv to read a paper on any topic; I can understand what's being talked about in the introduction and in the conclusion/summary, even if I do not understand the body of the paper.

    Since I have apparently misunderstood even in summary your paper; my request is for clearer explanation.

    But if you won't try to explain in simpler words; that is your choice.

    vongehr
    I cannot find your definition of "many worlds".
    Item (6) is about "world", toward the end of Item (6) there is "many world".
    I also see no definition of "tautological modal realism."
    Item (6): "I define “tautological modal realism” as ... "
    Good article.

    As ever I must play devil's advocate for naive relism (I never embraced it but you always accuse me of it so what the hell, I ll play along...) So what I would say is that you underestimate the psychological resistance to quantum MW. The precedent set by SR is nowhere near as challenging. Certainly the temporal ordering of space-like separated events (and therefore actualization of a possibility if there is such a thing) is modal to any particular observer, but that just tells us that the ordering of A, B, C is meaningless where the events are scattered around. No surprises there: the modality is merely a matter of perspective, there could still be a completely fixed block universe in SR. If anything the unintuitive nature of Minkovski spacetime is more troublesome than the "relative" bit.

    However I agree that SR and the idea of a fixed past in the past light-cone has a missing link: something must be provided which allows for one of several different possibilities to be actualized. The problem is, whatever is actualized for one observer evenytually gets actualized in the same way for all observers, there is no modality (in your sense of relative reality) at all, no different worlds, no different histories - all we have to adjust to is using invariant quantities and not insist on our personal rulers and stopwatches.

    What is outstandingly clear, though is what we are actually looking at is the simple(!!!) physical quantum fact of superposition. If we were a little less knowledgable we might seek to explain statistics by some random process and there would be no motivation for talking about tautological modal realism - except perhaps as a quirky bit of philosophy. The mysterious god "Random" would actualize certain possibilities and not others. Sure, the possibilites were equivalent before the event, but afterwards they are not. Why say they they are fundamentally so? This after all is what most people mean by random. Modal realism is only tautological (or only has a tautological variety) if the possibilities remain equivalent for ever.

    Which is described by the Schrodinger equation. Without physical quantum mechanics confirmed in every test, we would simply say that some equal worlds are more equal than others.

    Which brings me to my final comment. If I have followed you correctly and the above is more-or-less correct, then the central amazing fact requiring the whole paradigm shift is summed up in one word: superposition. Different worlds are temporarily observable *together* (with all the obvious caveats of what that actually means). Nevertheless, most people will, I feel sure, want to know whether the worlds separate and mostly die or whether they all live on indefinitely. QM as we know it would say the latter, but are we missing a very big window for "actual actualization" of a "really real" world and just getting carried away with the fact that nature explores all possibilities? Has physics eliminated the possibilty that most of them decay away hyper-exponentially, thus FAPP keeping One World after all?

    And just to reiterate - I am playing devil's advocate here.
    Heck, if nature keeps its options open for ever, why shouldn't I?

    vongehr
    you underestimate the psychological resistance to quantum MW. The precedent set by SR is nowhere near as challenging.
    I have written many times here in my column that the problem with QM is trivial if it were not for the huge fear that social animals have evolved against anything that even potentially suggests that they are not free, responsible agents (e.g. here, but that article does not get into the evolutionary aspects or the fear of cultural relativism etc). Yes, Everett relativity is much more severe than Einstein relativity in this regard, I think I even wrote about this in my recent QRC paper on the archive. It is a point that is not underestimated by me but a point one cannot write about in academia! It gets immediately rejected precisely because of that fear. You are barking up the wrong tree here.
    there could still be a completely fixed block universe in SR.
    There is without tautological modal realism. Explicitly written in item (9) of the paper.
    we might seek to explain statistics by some random process and there would be no motivation for talking about tautological modal realism
    The motivation is that you want to explain the randomness with your model and not have it external and god given to your model, starting a regress. That is another of many ways of saying that tautological modal realism belongs to the fundamental theory by definition. Randomness, like time, either is explained by the model or it is not the fundamental model. There is no "flow of time". Flowing is an activity that would need an outside time. In the same way, there is no "fair randomness" (random randomness). The randomness is fully emergent from the MW model. No god necessary.
    If I have followed you correctly and the above is more-or-less correct, then the central amazing fact requiring the whole paradigm shift is summed up in one word: superposition.
    If you mean "requiring" as in "requiring now in physics", yes, supperposition/entanglement/interference/Bell violation (all more or less the same, namely alternative worlds being correlated stronger than classically possible) is what forces us to open our eyes now if we want to make progress in physics. However, one best thinks about it as not being an amazing fact but simply the necessity of that the different Alices and Bobs need to match up correctly. It is not so amazing then, but, as Wheeler correctly demanded, an utterly simple idea.



    What "progress in physics" would benefit the world (my world, your world, anything's world) by embracing this paradigm shift?

    vongehr
    Not sure what you mean. Progress in physics may not benefit the world perhaps. Perhaps just helps my world as the world of somebody obsessed with comming to terms with how phenomena are possible. May benefit your world if you are similarly pathological. Some may think that understanding QM is good in many ways. Of course, no suffering is subtracted from totality. ;-)
    Thank you for your honest and personal reply, you've grasped my meaning exactly. I was looking for some motivation to bear the onus of trying to understand this idea. My first thought of your reply was this new paradigm really doesn't matter. My understanding it isn't going to change my world or any world. But I am similarly pathological as you when it comes to this obsession. So, since it really didn't matter my disease was at ease, and I merrily jumped right in with several comprehensive readings of the essay and all the following posts. (Hence the delay in my response, and, of course, no suffering is subtracted from totality.) I'm glad I did, and I might have even found a beneficial reason for doing so.

    First, credit where credit is due. Being familiar with the rough draft, I am truly impressed with the work you did honing every word to a sharp precise meaning. It's not only what you wrote, but what you didn't write. A priceless economy of words. Wittgenstein would be proud of you definitions and terminology. I'm still not completely clear about it all yet, but I am learning. I would like to be as Positivist as you but right now my intuition is my guiding light. It feels so right, elegant in a way, just as I would expect from totality. With the help of internet resources, I am seeing better and better. My biggest problem is keeping track of all the open tabs of definitions and info of anything you mention that I'm not familiar with trying to understand every word. I've learned that when I skip over a word or something I don't understand my comprehension from that point on is dulled.

    So to sharpen some things up for me, I have some questions. A picture is worth a thousand words they say, but the Light Cone Structure Diagram is raising a thousand questions. I felt I was following you pretty good until I began pondering the diagram. And now I'm having problems even with trying to ask questions. Could you relate the text of (9) paragraph 4 - "Enter special relativity..." to the diagram and it's labels. I'm having trouble with the label SOME BOB (which Bob, any Bob, some? of which/any Bob? And the label RELATIVE TO BOB UNDETERMINED (BLUE), relative to who (MANY ALICES) or what (BOB"S DETERMINED PAST) and which (BLUE) (light blue, dark blue)? And is there any significance to the dark red area where the two cones overlap (correlation perhaps)? I hope you see what I'm getting confused by.

    The motivation is that you want to explain the randomness with your model and not have it external and god given to your model, starting a regress. That is another of many ways of saying that tautological modal realism belongs to the fundamental theory by definition. Randomness, like time, either is explained by the model or it is not the fundamental model. There is no "flow of time". Flowing is an activity that would need an outside time. In the same way, there is no "fair randomness" (random randomness). The randomness is fully emergent from the MW model. No god necessary.
    Ah I see your difficulty. You presuppose that there is a fundamental model that does this, you don't allow for the possibility that there are a few irreducible or arbitrary facts and that the fundamental description must include them as "givens". Randomness was, after all, invented to do exactly that: to let nature choose one possibility out of several equivalent ones without saying how it does it.  In fact fundamental randomness would have to deny that saying how is even possible.

    So I have to disagree with you when you say: "In the same way, there is no "fair randomness" (random randomness)." That's the point - randomness does not mean "random randomness", it means "fair randomness". Randomness = unpredictability; fairness = equal treatment, it's a different word. 

    I would agree that if there is randomness in the fundamantal description then it must be fair. However the fact that random implies preferential actualization of one world does not violate fairness - all worlds had the same chance :) Of course, as it happens, QM hands us fair randomness with Bell violations on a plate. That would please Occam. But I cannot see why such a "symmetry breaking" randomness should be excluded tautologically (by definition).

    So once again I find myself asking "am I missing something?"
     

     

    blue-green

    Here is a firsthand account of Wheeler being tautological about quantum's lesson, complete with a drawing. While sitting alone with him in his office in Austin, Texas in 1982, he started to draw a camera on my letter to him with one of his felt-tipped pens. He was thinking about how “no elementary phenomenon is a phenomenon until ...” As he drew his cartoon and wrote “TAKE #3”, he asked, “When is a take a take?” I blurted, “when it is taken”, and thus a tautological summary of quantum's lesson was born.

    Quantum Mechanics never says more than it has to say. I anticipated the tenor of Sascha's response above to my query, but not the specifics, so again, interference that is nigh impossible to reckon using naive realism, yet consistent with our separateness.

    Here is how Anton Zeilinger expressed the paradigm shift in 2006. [begin quote]

    We've learnt in the natural sciences that the key to understanding can often be found if we lift certain dividing lines in our minds. Newton showed that the apple falls to the ground according to the same laws that govern the Moon's orbit of the Earth. And with this he made the old differentiation between earthly and heavenly phenomena obsolete. Darwin showed that there is no dividing line between man and animal. And Einstein lifted the line dividing space and time. But in our heads, we still draw a dividing line between "reality" and "knowledge about reality", in other words between reality and information. And you cannot draw this line. There is no recipe, no process for distinguishing between reality and information. All this thinking and talking about reality is about information, which is why one should not make a distinction in the formulation of laws of nature. Quantum theory, correctly interpreted, is information theory. [end quote]
    www.signandsight.com/features/614.html

    vongehr
    BG - thank you for your insightful comment (you must have a cold again).

    Zeilinger's anti-realism is implicit in my emergent indeterminism [Items (7) and (8) of the essay], because the latter refuses the difference between "subjective" and "real/fundamental" indeterminism, because it is a verification transcendent distinction. Wheeler's "taken when it is taken" is implicit in refusing actualization [see whole essay].

    Wheeler's "taken" and Zeilinger's anti-realism, though both correct (!), have not been shown to demand the quantum.  They do not imply QM-probabilities (Bell inequality violation).

    Moreover, they should be utterly simple, but they would not even be expressable in a proper terminology, since concepts like "real" are likely absent ("modal realism" is a compromise in order to stay comprehensible to people). My suggestion is similar to Einstein's elevator thought experiment [see Item (10)], which is a simple, because quite hands-on physical scenario that demands general relativity (gravity equivalent to acceleration). I say that the alternatives (worlds) physically match up (one Alice per Bob) and that this is the 'interaction' between alternatives (worlds) that is the very core of QM. I also have not fully shown how this implies Bell-violation! However, while Wheeler/Zeilinger get fundamental uncertainty (~ emergent indeterminism) out of their 'simple ideas', which is not the core of QM (you could get uncertainty even from residing in an Einstein-ether that has a temperature proportional to the Heisenberg constant), my 'simple idea' gets the very core of QM, the very aspect that makes QM fundamentally non-classical, namely that alternatives physically 'interact' (~ correlate stronger than classical correlations can possibly explain). The Bell-violating probabilities should fall out of thinking this through in the EPR setup [Items (20) and (24) of the essay], likely via David Deutsch's approach and/or Relational Quantum Mechanics.
    blue-green

    No cold here. A dash of nutmeg. You have to be open to all the ways I can write.

    The famous elevator example has to do with how there is no physical distinction for an observer inside as to whether the elevator is a protective capsule far removed and jettisoning away from Earth with an acceleration of one g-force … OR …. at rest on the earth's surface.

    With tabletop lab bench physics, there are many ways an optical setup can be rearranged and produce the same clicks in a counter. From the actual data/takes and no more, there are whole equivalence classes of arrangements of mirrors and beam splitters that can give the exact same results. If you are not specifically told in advance how the entire experiment is arranged, then to explain your data, you have to INCLUDE every possible way it could have occurred. Mathematically, you treat each possible way as a quantum amplitude and you then ADD all of these ways to get a resultant. It is essential that each plus sign in the addition (or integration) is read as meaning OR as in “this way” OR “that way.”

    In fact, you need the more rigorous XOR, and this is because of the fundamental indivisibility of Planck's quantum of action. An electron is never observed in partial form. Same with so many other features of particle physics. I don't think there is a basis for deriving this indivisibleness in Sascha's essay. Bohr called it the quantum postulate.

    Bohr did understand how each data point is an expression of an entire experimental or experiential setup (or equivalence class of setups). This is how he saw fundamental physics as being holistic and non-local.

    Anywhere along a pathway for photons, one can add or subtract Mach-Zehnder like devices to pull beams apart and recombine them. These devices can be on a macro scale or they can symbolize virtual processes, which can be as large or small or quick as you wish. The end data can still be the same. The devices can also be moving at fantastic speeds relative to the lab bench and change the temporal ordering of the mirror placements from before to after a photon is already in the system. Or one can equivalently, with no observable difference, insert a recombining mirror after a photon is already making its way through the whole system. This latter example is what Wheeler called a delayed-choice setup.

    With all of these equivalent yet mutually exclusive ways to generate the same data, one's theory of information has to be careful to not read more into the final data than what it actually implies. “It is better to keep your mouth shut and appear stupid than to open it and remove all doubt.” (from a T-shirt in Mark Twain's hometown).

    There is one more vast way to rearrange an experimental setup without causing any observable difference. Each atom of iron in the clamps, for example, can be interchanged with any other atom of iron, because Fe atoms are all one and the same and devoid of any individuality. Therefore, in order that one's information theory not spew meaningless nonsense (as if each atom of iron were uniquely different and distinguishable with a personal history), one's theory has to acknowledge that it cannot tell whether fundamental particles have traded places with each other. 

    The identity problem asked about below is solved in the way QM handles all of the equivalent ways to generate the same data.

    When two or more particles are being mapped, all of the complications of the single particle case have to be MULTIPLIED against all of the new complications, over and over again for each added ingredient. It is not a matter of adding one particle and then another, like adding marbles to a box. It is more like adding a whole new box or space with each additional particle. This is why a 3-dimensional quantum problem with one particle suddenly becomes 6-dimensional with two particles. You have to MULTIPLY the available dimensions, instead of just highlighting more points within a given dimension. It is no small task to be open to all of the indistinguishable ways in which the same final data can be derived, and yet, in spirit, it is akin Einstein's equivalence principle. This is why Bohr wrote that quantum theory is a natural extension of relativity.

    Quantum theory is derived, in part, from the necessity of indistinguishable ways of getting an answer to match up and agree. Mathematically, the key is let the colloquial AND actually be XOR, and to let the colloquial OR to be the tensor product of entire spaces.

    vongehr
    this is because of the fundamental indivisibility of Planck's quantum of action. An electron is never observed in partial form. Same with so many other features of particle physics. I don't think there is a basis for deriving this indivisibleness in Sascha's essay. Bohr called it the quantum postulate.
    Quantum in QM is not like atomism. The quantum is not due to ontologically indivisible things called quantum particles. It emerges from the fact that we interact, that the information change through the interaction is at least a yes/no answer. Bohr called it "quantum postulate", so it is certainly not the "utterly simple idea that demands the quantum" if we simply postulate it.
    Quantum theory is derived, in part, from the necessity of indistinguishable ways of getting an answer to match up and agree. Mathematically, the key is let the colloquial AND actually be XOR, and to let the colloquial OR to be the tensor product of entire spaces.
    You refer here to the information theoretical approach, which is fine, since the AND/XOR seems to be precisely what many worlds is all about: You don't just include the one actualized world, but you have that AND/XOR that makes many different possibilities interact in the formalism. It is many worlds without explicitly saying so.
    blue-green

    The minimum threshold for an interaction to occur is one Planck unit of interaction. Your follow up essay does not explain why the value of Planck's constant is not zero. A fuller theory would derive its actual value. Bohr could not explain it, yet he took it as being a fundamental starting point. That's why he called it a postulate. Maybe to you it's like Euclid's parallel postulate and can be left out to get to a more extensive description. I don't know how to take it out or whether doing so would be advantageous.

    I'm not satisfied with my description above of XOR. Before an interaction has occurred, we entertain in our minds the notion that a particle can go one way, or another way, or many ways at once. It's a weak mental construct. Individual particles are never observed to physically split up and be detected across many detectors in fractional amounts. The X in XOR comes into play when a detector clicks with a whole particle; it's a little reminder that the quantum postulate is in effect and h is non-zero and a fixed constant and barrier for something tangible to happen.

    blue-green

    As any non-believer can tell you, just because you say it is so does not make it so. If something is convincingly “emergent” from a deeper foundation that can derive Planck's constant or quantum uncertainty, one has to have a full numerical calculation (of the half-life of Carbon-14, for example) in which it is perfectly clear which parts are being derived and which parts are filled-in using empirical data.

    vongehr
    I clearly wrote that as far as I understand, the special relativistic part is empirical input (though others have motivated Riemannian geometry as a-priori from operationalism). I suggest the way to derive the fact that different alternatives must correlate in stronger than classicaly possible ways (the core of QM), which should arrive at the quantitative amount of Bell violation.
    The minimum threshold for an interaction to occur is one Plank unit of interaction.
    Er, no. Just read the Wikipedia article on the magnitude of Plank units.
     
    There is nothing in QM to suggest the universe is granular, quantization emerges as eigenvalues in particular situations: jumping from level to level requires the difference in energy by definition, but there is nothing to say the difference itself is a threshold or in any other sense fundamental.
    ... explain why the value of Planck's constant ...
    If you mean Planck's constant and Heisenberg's Uncertainty Principle, this is a very badly taught subject. Suffice it to say that if you constrain the lateral position of, say, a photon by shoving it through a slit, its lateral momentum will become uncertain according to HUP. However, you can bet your boots that when it hits a screen it will suddenly turn out to have had a very precise momentum all along - how else would it have ended up in one place? Indeed if you actually measure conjugate quantities directly, the accuracy is limited by experimental error, not by HUP. In "old" quantum terms they are not predicatable to a better accuracy than HUP, but they are certainly measurable to any accuracy your instruments can manage.

    So even according to HUP, there is no threshold for, neither is there any inherent smudging of  physical quantities at some "deep quantum level". We certainly have to ditch the idea that a particle takes a particular route. Imagination says "But what if we could take a peek and see where it goes?". QM says "You can't do that without making it a different piece of apparatus. Why ask 'what if' if your scenario cannot happen?" However, accepting that QM speaks of unfolding superpositions where everything happens is not the same as saying it talks of thresholds below which nothing happens.

    It's a weak mental construct. Individual particles are never observed to physically split up and be detected across many detectors in fractional amounts.
    Debatable. Photons are usually a) absorbed by the detectors b) not detectable en route. These make detection at multiple detectors difficult to impossible. Charged particles are much easier. Electrons do NOT manifest themselves as point charges except when sadistic particle physicists smash them together and they quite naturally curl up into little balls like hedgehogs trying to avoid being eaten. An electron which is happy and unthreatened likes to spread itself out - you would insist it must be in a particular place, but that was the problem with the classical model of the atom: the orbiting electron would radiate. In fact electrons in ordinary matter are nicely de-located which is precisely what you say does not happen. This produces quite different material-to-material (Van der Waals) forces from what jiggling point-electrons would create.
    blue-green

    Mr. Potter, if you could point to a specific experimental situation in which a detector is triggered with less than a quantum of action, you'd have a point. And let's not quibble over h or h-bar or half-spins. The fact that spin itself does not come in say 1/3 units or in fifths should tell you something about this quantum jumping. Or maybe we shouldn't let facts get in the way here.

    Yes, the spacing between energy levels depends on boundary conditions, the whole experimental setup. Maybe you can clear this all up at the Bohrfest next year!

    Or maybe we shouldn't let facts get in the way here.
    The only relevant fact is that you said "Planck units" not "quantum of action".
    blue-green
    Quibble quibble. I said "The minimum threshold for an interaction to occur is one Planck unit of interaction."

    This interaction has the same physical units as those for spin and angular momentum and pairs of conjugate variables in general. It is the same type of action as employed in the Principle of Least Action. Yes, I was too lazy to look up its approximate value and type it out with its proper units. I also forgot that someone like you might skip over "interaction" and conflate it with Planck units of length or Planck units of time or worse.

    The essential point is that we are dealing with a non-classical lower bound, a finiteness that Bohr called the quantum postulate, because he could not derive it and assumed it as a radical starting point 99 years ago.
    Yes, someone like me is very likely to misread your posts as meaning something to do with the words you actually use rather the ones you should have used but did not and which remain an occult mystery inside your head...

    Have fun with your "damned quantum jumping". I see no reason to tell the story of the universe (pace Sascha - make that totality if you wish) as a series of eigenstates and "the rest" where it's in superposition. YMMV.
    blue-green

    I was hoping for some new graphics from your studio. Looking back, I see that before you made your complaint felt, I had already referred to “the fundamental indivisibility of Planck's quantum of action” just below the tricky coyote.

    I don't know what to make of Sascha's claim that “Quantum in QM is not like atomism.” Its most accessible lesson is in the discrete composition of the world with all its repeatable and interchangeable parts, a rather wild claim in the olden days to anyone but a chemist, yet common place today with digital art and records … and copy-cat stores.

    Another lesson would be to not take images too seriously. Learn to laugh at yourself. Radical Muslims have not picked up on that. Their children's children will scratch there heads and wonder what the fuss was about.

    As Okthen writes at the bottom: "I think our basic physical assumption is tacitly and implicitly some kind of representational realism. I for one never mistake our toy model (e.g. physics theories GR or QM or String theories or big bang) for reality.”

    Methinks the majority of people are well over and beyond “representational realism.” Those who aren't look really dumb. It would be hard to enjoy a joke with them.

    Graphics and anything likely to be remotely entertaining are, for the time being, withdrawn until the farce of my not being able to blog without grovelling for special permission is lifted. I was going to explore the restriction of phase-space given reverse causality as part two of my Time Travel Paradoxes so that the toy model with its pretty pictures could be fleshed out with decent science.
    I don't know what to make of Sascha's claim that “Quantum in QM is not like atomism.” Its most accessible lesson is in the discrete composition of the world with all its repeatable and interchangeable parts, a rather wild claim in the olden days to anyone but a chemist, yet common place today with digital art and records … and copy-cat stores.
    Okay, lets stop the bickering over our respective use of words. I think you have a different view of what QM teaches. You demanded I produce an experiment in which less action than h-bar is involved. Spin, admittedly, is quantized this way but how would you deal with a position-momentum pair in those terms? Where is this relatively coarse quantization in a Young's slit experiment? Uncertainty is not the same as quantization, in fact uncertainty is particularly obvious when the eigenvalues are continuous - photons being diffracted over a continuous range, for example. How does this show "the discrete composition of the world"?

    blue-green

    “The discrete composition of the world” … is easy to show in double slit photon experiments by simply turning down the intensity (which is to say the number) of photons entering the apparatus during an interval of time. With just one photon entering the system at a time, the detectors "click" with a random and uncertain discreteness that is reminiscent of a scintillating screen for detecting radioactivity.

    I double checked my spelling of discrete, and yes, I mean consisting of separate and distinct parts that are detached, independent and disconnected from one another. It is paradigm shifts removed from the popular beliefs that we are all one, connected, joined and united under one god .... ommm.

    For a graphic illustration of a single photon gun, see the movie here:

    http://research.physics.illinois.edu/QI/Photonics/kwiatmovie.html

    Of course, you knew all of this … It's hard to say farewell to monotheism.

    Obviously photon interactions are discrete! Your claim was, or appeared to be, that all interactions involve at least one "Planck's constant" of action. My query/confusion is how this works when the photon interacts with the slit, not when it interacts with the detector. My understanding is that with a narrow slit, the lateral momentum is not quantized but is continuous. So what is it that is quantized in this interaction? Or do you not agree that the light interacts with the slit? Perhaps you only admit something is an interaction if it is quantized?
    blue-green
    This is what Wheeler was pondering with "when is a take a take". A positivist only takes the actual detections and recordings literally. The rest is as Wheeler would say, "papier mache filled between iron posts of observation." He had a drawing for that. I need to get some stone work done; freezing temps here at night already. Hopefully, Sascha or one of Wheeler's real students will fill in. Wheeler was a Bohrian through and through, making a certain line of attack on even numbered days and then counter-attacks (or complementary ones) on odd numbered days. He loved it and was light on his feet.

    Discrete, independent events. Fortuitous clicks. And yet, correlated. This is the tricky part for which I have to defer to the professionals.
    Well, since environmental decoherence took over :) the need to say when an observation is complete has become less urgent. I would surmise that with Sascha's  approach (TMW), there is no need to say at all. An observation is simply an interaction of interest which throws the system into a superposition, then decoherence, which creates the Born probabilities in the records. But it's still a superposition of observer-worlds. There is then no "completion of the observation". Your split-path diagram shows this. It's logically impossible for a particle to go both paths in a single world but it's eminently possible in a superposition, which is precisely what QM describes.

    I need to mug up on this stuff, I don't have snow to worry about but there is much to distract from getting to grips with it all. Roll on retirement!
    Sascha, well done. I've read this essay in final form through once carefully, and already it hangs together for me very well -- and this is certainly because I have previously read your many other essays on this blog which already presented most of these ideas in pieces. (The more careful wordsmithing is quite apparent in comparison, but that isn't practical to do all the time on a blog.)
    My considered feedback for you is that as you make the more directly stated connections here to the philosophy of Wittgenstein (beyond the physics) it becomes more difficult not to acknowledge the *other* elephant in this same philosophical room: the problem of *identity*.
    Granting all the points in this essay, and the appendix too (points 1-24 inclusive), can it remain unasked (and unexplained, or unexplainable, or even whether it is meaningless to ask?) why tomorrow *I* will wake up as the Bob who is wearing socks and not the sockless Bob with an equal amplitude sum-of-paths? For you see *I* will wake up in *exactly one* of those futures, and another Bob, a fundamentally *not me* Bob will wake up in the other.
    ...Why?
    Squarely facing this question, above and beyond a linkage to the probabilities and amplitudes of Born's law, is an inescapable requirement to approach agreement on a meaningful explanation of the relation between the situation from a particular observer's point of view, and the tautology of all-possibilities-which-are-possible.
    Once you grab this particularly well-squeezed philosophical toothpaste tube, it's not really credible to think it can all be fit back into the tube simply! Yet nor can it be easily waved away.

    vongehr
    Yes, Identity is important. Your questions, both, on identity and on actualization of one single future, are in detail covered in the new article Indeterminism comes before QM. Basically, we need to distinguish the fundamental observer (observing one present) from the fundamental describer of totality.
    colinkeenan
    It's been a while since I've spent time trying to understand Sascha's essays. The only reason I could follow most of his FQXi entry is that I had read many similar ideas in his comments and essays from close to a year ago. Now, I've read many other articles through links to this one and his next, and realize he's spelled out a lot more since I last read in depth here.
    In order to understand his "utterly simple idea", the reader needs motivation first. For me, motivation came from watching one of those modern science-is-weird documentaries, probably with Alan Greene, but I don't remember. I wanted to find what documentary it was before making this comment, but maybe someone else will know what it was. I would like to have a link to a particular cartoon in the documentary or at least a couple of pictures from it.

    After already explaining the indeterminacy of quantum mechanics (I don't remember how), the show next tackled the relativity of simultaneous events in Special Relativity. I don't have a clear memory of the cartoon they showed, but it went something like this: an alien rides a bicycle on a planet millions of miles from us. While riding in one direction, a simultaneous block of space including the alien also includes our 19th century past. But, by turning around and riding the other direction, all at normal bicycle speeds, a simultaneous block of space including the alien also includes our future.

    Watching this while also thinking about the usual Alice and Bob stuff, and also while thinking about comments I remembered Sascha making, it all clicked for me. I even thought the show was about to explain how this leads naturally to a many-worlds idea. Because, it seemed obvious to me if the Alien could be simultaneous to our past while riding in one direction, and simultaneous to our future in another, then our present was not yet determined for the alien, meaning that things that we consider ourselves to have already done could be different by the time the alien would learn about them. This makes the Alice and Bob problem easier to understand as well. In one special-relativity frame of reference, Alice measures first; in another Bob measures first. When Alice makes her measurement, it's fair to say Bob's measurement hasn't been determined for Alice yet. The fastest Bob's measurement can become determined for Alice is the amount of time it takes for both measurements to be included in Alice's past light cone. In other words, the amount of time for light to travel from Bob to Alice. Until that time, when Alice and Bob's measurements meet, the correlations between them don't exist yet because from each person's point of view, the other's measurements aren't determined yet. The whole mystery behind Alice and Bob is that if they record their measurements simultaneously, then how can those measurements be correlated with each other beyond what is classically possible? It's as if either a signal traveled instantly between them or that the measurements changed at the moment they were compared to look for correlations. Realizing that it's not until a signal can join the measurements that they can be included in the same light-cone goes a long way to solving the problem if you accept that all outcomes are still possible before they are included in the same light-cone.

    Of course, I was disappointed when the show drew a completely different conclusion from the alien being simultaneous to our past in one direction and simultaneous to our future in the other direction. They concluded that everything past and future is all part of one block that already exists. This is a natural conclusion when just looking at the relativity of simultaneous events in Special Relativity, but the show had just pointed out the fundamental randomness of quantum measurements. These ideas definitely seem contradictory, so why didn't the show say anything about it? Having the quantum randomness while also having everything set in stone in advance as a block universe only makes sense if the randomness was pre-planned as if to deceive us for some reason. As Sascha points out in his FQXi entry, believing that would seem to be on the same level as believing fossils were planted by God making life on earth only seem to have been around for millions of years when in fact the world is only hundreds of years old.

    I had never accepted anything to do with multiple universes before, including this model realism Sascha is pushing. But, seeing all in context while watching that documentary made me realize the only other alternative that I understand is even more ridiculous. I haven't been able to understand the mainstream interpretations as explained by Lubos Motl.
    colinkeenan
    Gerhard suggested to me that the documentary I was remembering may have been The Fabric of the Cosmos. He was right. The animated section that I remember lasts for about 3 minutes starting about 23 minutes into the 2nd episode, which is all about "time". The Fabric of the Cosmos is actually a 4 episode series of science documentaries narrated by Brian Greene and based on his book. The only part of all 4 episodes that I remember was what I refer to above. The first episode is about space and I think they mention quantum mechanics in talking about the void, but I may have watched these episodes out of order because it's the 3rd episode that's about quantum mechanics and I don't think he mentions quantum randomness in the episode about time. My incorrect memory made for a more dramatic and effective comment though. The 4th and last episode is about the multiverse, but I'm sure he doesn't make the connection between many worlds and special relativity or else I would've remembered it.
    vongehr
    Of course, I was disappointed when the show drew a completely different conclusion from the alien being simultaneous to our past in one direction and simultaneous to our future in the other direction. They concluded that everything past and future is all part of one block that already exists.
    Precisely - that is the big mistake [Item (9) of the essay], and this is why I am so confident about my approach. You have to do it my way or you will end up with complete histories of worlds just being painted by god, all stochastic being devine pre-arangement. That is why modest atheists must accept many worlds and even the multiverse.
    Sascha, Sascha, Sascha! Not everyone thinks the idea of God is sufficiently ludicrous that you can discredit any argument simply by waving the word "god" at it.
    vongehr
    I do not reject medium level creaters, nor finite regress ethers, but fundamentally they are not valid answers.
    So here is the deal.

    Your paper has motivated me to explore a lot: Wittgenstein, non-locality vs. local realism, Everett relativity, your papers on arXiv, Robert Stalnaker's book Mere Possibilities, realism, scientific realism, modal realism, etc, etc... Some of these ideas I was previously interested. As well some of your other pares (e.g. on two-times) I will read carefully.

    So let me add a few remarks (working opinions): I'm not trying to challenge you just better understand your meaning.
    I've made the bold assumption that you are not a sophisticated highly educated nut-case.

    So let me proceed with my public education (far from complete).
    "our basic physical assumptions is a tacitly held direct realism"
    I don't think so; I think our basic physical assumption is tacitly and implicitly some kind of representational realism. I for one never mistake our toy model (e.g. physics theories GR or QM or String theories or big bang) for reality. Our best theories GR and QM are very very very good in their respective domains of relevance BUT they disagree. I do not expect them to be overturned (in the sense that Newtonian gravity and mechanics was not overturned) by incremental changes. I expect them to be replaced by something revolutionary.

    "There is no verifiable distinction... The absolute/relative distinction fails."
    OK but so what.? Why does it matter? I mean the number 7 is a concept not a physical entity in our world. Where we might argue that pi is more than a concept; it is a physically measureable entity inour world; maybe this is your meaning. So maybe an alternative world has 7 instead of pi in certain measureable equations. But if another world is spatiotemporally isolated from our world and causally aren't we in the realm of the metaphysical or mathematical not the realm of the physical. So I assume the distinction absolute/relative doesn't matter physically. Why does it matter logically, metaphysically, philosophically.... unless such choices give different insight or different logical tools to physicists. So why?

    ‘Quantum mechanics promotes the mere "observer of reality" to the "participator in the defining of
    reality." It demolishes the view that the universe exists out there.’ Wheeler
    OK, yes, yes.

    "What if these ( “universe” and “exist”) cannot be consistently defined"
    I assume by godel that they cannot be defined consistently.

    "When doubting the universe’s “reality”, my description defines what “my world” is. "
    Wait a minute, who "doubts the universe's reality" or the "self's reality" or even any "action" or "objects" "reality.
    Just because my description is limited by language and is incomplete (Godel again); does not mean that there is no "reality" or "universe". It just might mean that our logic cannot consitently define anything. "If I could understand the flower in the crannied wall", so to speak; but I can't.

    " I need an extreme ‘positivist’ style concerning significant language in order to communicate glimpses of a future paradigm"
    Maybe but an extreme positivist' style is every bit as flawed (via Godel) as any other style. Unless you want to argue that Einstein used an extreme positivist' style when he figured out how to interpret the Lorentz equations or when dirac figured out the Dirac equations. Teach me.

    "Totality encompasses the total of all possibilities... Some unobservable is possible (e.g. virtual particles, tachyonic off shell paths, potential histories, QM fluctuation ascribed to stable ground states)."
    OK but you need to be clearer. Are these unobservables part of your totality?
    -- Physical unobservable only? i.e.it's possible that the moon could have been 10% smaller. Yes?
    -- mathematical unobservable? i.e. it's possible that Poincare conjecture is incorrect but unprovable No/yes?
    -- grammatical unobservables? i.e. the next poem by Tagore (that was never written). No?

    "QM obeys Murray Gell-Mann’s Totalitarian Principle: Everything not forbidden is compulsory."
    OK, but only within the domain in which quantum mechanics is a correct physical theory.
    Thus if something is not forbidden but not observed; then QM is outside it's domain of relevance. AND we make a new law that such and such is not observable despite it not being forbidden by quantum mechanics.

    "Relativistic QM is the most precise theory, perhaps even exact. No refuting anomaly has been found... QM is
    about the totality of alternatives, both observable and unobservable. "
    No. Of course you are correct about special relativity quantum mechanic. But there is no general relativity quantum theory. Hence quantum mechanics is untested in the case of gravity (so far)? And certainly many many physicists search experimentally and theoretically for the next revolutionary theory. "So it is possible that QM is NOT about the totality of alternatives, both observable and unobservable." That's way to much hubris to put on the shoulders of any mere human toy/model physical theory.

    "Much of what is claimed to be entirely due to QM was evident to some probably thousands of years ago"
    OK I'm listening.

    "Many despise such world-talk and it is not perfect"
    No despise here; it seems like a useful mental tool concept; continue.

    "I define “tautological modal realism” as the acceptance of fundamental equivalence (4, 5) combined with labeling possibilities “real”, be they worlds or not. "
    OK but so what?

    "fundamental physics is (not merely!) a description."
    Really. Fundamental physics is for sure about fundamental symmetries. But are we sure that we have all of the fundamental symmetries. And know when there is broken symmetry. I for one expect many surprises in our fundamental understanding. A phase change is breaking of some kind of symmetry. There are so far 17 (all unpredicted) phases of water molecule. If QM cannot predict the phases of a water molecule; then how do we pretend that QM can predict the phases of our universe (i.e. alternative universe). I know you are not talking about predicting; but I am not sure that a chemist would agree that QM could even in principle determine is a certain phase of water is allowable or not.

    My point is that only the universe tells us what is allowable; all else is hypothesis and speculation. And every one of our best theories has a domain of relevance beyond which it has not been tested. And the evidence will be less correctly interpreted by a less applicable theory. Hence use GR here and QM there.

    "totality is totally determined. Totality does not have a future; it includes all futures. "
    As Bill Clinton said, "It depends on what your definition of 'is' is" and it depends upon what your definition of

    "Much of what is claimed to be entirely due to QM was evident to some probably thousands of years ago"
    I'm still waiting for an example. but let's move to your next assertion.

    "Tautological modal realism and emergent indeterminism do not need QM."
    OK, I'm listening.

    "After a coin toss, heads and tails are both actualized relative to the observers that witness heads and tails, respectively. This alone does not demand QM, but with this in mind, Einstein could conceivably have anticipated the core of QM long before Everett. "
    Well that's definitely not in the realm of either an physical observable , an unfalsifiable idea, or necessary physical unobservable. It may be metaphysical necessity, and logically follow from your defintions; but how exactly was Einstein to turn this into the dirac equation or the uncertainty relation of quantum mechanics. A chalk board demonstration please.

    "Special relativity already shatters the classical past into a collection of possible past light cones"
    Yes
    ", which each are an observer’s determined past."
    Not what I would think today, but maybe Einstein would. But yes, that's what the classical special relativity model would say.

    "if Bob’s future is not determined, neither is all of his past."
    OK, yes Einstien and yes 2000 years ago; this insight was available; but outside of the theories of physics. Outside of any theories of physics even today. We are into metaphysics; which may lead to a new testable physical theory. i.e It is possible that one of the theories that predict extra dimensions will be supported by experimental evidence.

    But so what? What is the great physics insight that is not being taught to children or adults?

    "Why could a physicist have anticipated QM in this way?"
    Hey you know QM; show me how you now can post develop QM, e.g Shroedinger's equation, this way.

    "the ‘mechanism’ that has access to the alternatives to accomplish that ‘interaction’ between them. "
    Wait a minute, the mechanism that allows interaction between Bob and Alice is time or spacetime or NOT (i.e no interaction between them).

    "That ‘interaction’ (13) is precisely what QM with its superposition and entanglement and interference
    between possibilities is, and its necessity demands the quantum. "
    Well for sure these are some of the concepts of QM under discussion and not fully understood yet. Hence hypothesis and tests; and more hypothesis and tests. I don't see anyone take a deep breath and a clear mind jumping directly to QM or to the correct String theory or...

    "Nevertheless, I think this is the simple idea."
    I disagree, this is not the simple idea.

    "QM correlations ‘entangle’ mutually exclusive worlds "
    Maybe, not sure. One unsolved problem's http://en.wikipedia.org/wiki/Unsolved_problems_in_physics is:
    "Locality
    Are there non-local phenomena in quantum physics? If they exist, are non-local phenomena limited to the entanglement revealed in the violations of the Bell Inequalities, or can information and conserved quantities also move in a non-local way? Under what circumstances are non-local phenomena observed? What does the existence or absence of non-local phenomena imply about the fundamental structure of spacetime? How does this relate to quantum entanglement? How does this elucidate the proper interpretation of the fundamental nature of quantum physics?"_______ So we don't really know a lot about this yet.

    "Spooky Non-Locality more Unreal than Modal Realism. EPR is usually presented as leaving two options available, namely either non-locality or modifying realism. "
    Yep those are the apparent choices, the only one's anyone sees yet.

    "Without modal realism, non-locality violates Einstein-locality.. many physicists still opine that non-locality is merely a ‘really complicated’ correlation."
    Yep, we'll have to watch how theory and evidence gather and help define the next important physics idea that like the principle of equivalence lead to GR.

    "Non-locality destroys direct realism anyway; modal realism is therefore more conservative. "
    Well, I'm not looking for the next incremental "conservative" physics idea; I'm waiting for the next "revolutionary" physics idea.

    "If space is a box with objects ‘really’ at certain locations inside, localism is implicit."
    Not if spacetime is nonorientable. Here's a small example http://arxiv.org/pdf/gr-qc/0202031v4.pdf

    ") Modifying realism undermines that ‘space is really out there’."
    Ahh, well if spacetime is nonorientable then there is no out there versus in there is there.
    Physicsists and mathemeticians build oreintable model universes because the mathematics is easier than a Klein bottle universe of 10 or 11 dimensions that are actually reciprocally curled (i.e tiny to you is large to me and vice versa). Just a possibility for a description of our visible world or many just a possibility for an alternative world; but if such an alternative is not forbidden them well, you know how that goes.

    OK that's my two sense. Very nice paper.
    You forced me to learn a lot.
    Excellent paper. I'll read more of you.
    And I may find myself agreeing more or less; but certainly learning.
    Thank you.

    vongehr
    Thank you for your detailed comment. I hope the following helps:
    "our basic physical assumptions is a tacitly held direct realism"
    You quote out of context. The quote is: “The most severely misleading of our basic physical assumptions is a tacitly held *direct realism* and its way of *physical actualization* of future.”
    I don't think so; I think our basic physical assumption is tacitly and implicitly some kind of representational realism.
    That may well be also correct but is not the topic of my essay.
    "There is no verifiable distinction... The absolute/relative distinction fails."
    OK but so what.? Why does it matter?
    It matters because if a distinction fails, it cannot be made. If people make it, it leads to inconsistencies.
    who "doubts the universe's reality" or the "self's reality" or even any "action" or "objects" "reality.
    Many who work on the foundation of QM for example, many philosophers, and certainly anybody who wants to be aware of the constraints of a fundamental description that may be forced to define “reality”.
    "Totality encompasses the total of all possibilities... Some unobservable is possible (e.g. virtual particles, tachyonic off shell paths, potential histories, QM fluctuation ascribed to stable ground states)."
    OK but you need to be clearer. Are these unobservables part of your totality?
    The answer is right there: "Totality encompasses the total of all possibilities”
    “OK, but only within the domain in which quantum mechanics is a correct physical theory.”
    Yes, but I later do not talk about QM but about the fundamental theory from which QM derives. That may imply corrections to QM as we know it.
    "Relativistic QM is the most precise theory, perhaps even exact. No refuting anomaly has been found..." No. Of course you are correct about special relativity quantum mechanic. But there is no general relativity quantum theory. Hence quantum mechanics is untested
    This does not change anything about it being the most precise theory and no anomaly being observed. I am not excluding further insight into whether the fundamental theory is or is not a further modified QM. I am saying that the fundamental theory is tautologically that way, and from it follows QM.
    My point is that only the universe tells us what is allowable;
    The universe just tells you what smelly corner of totality you are finding yourself in.
    "totality is totally determined. Totality does not have a future; it includes all futures. "
    As Bill Clinton said, "It depends on what your definition of 'is' is" and it depends upon what your definition of
    That is why I defined it before!
    "Much of what is claimed to be entirely due to QM was evident to some probably thousands of years ago"
    I'm still waiting for an example.
    The example is the socks. It is deliberately silly in order to discourage those who claim taking no-socks initial conditions as "fundamental" is a possible choice for defining "fundamental". Such may be consistent, but silly. It will be highly inconvenient to describe totality.
    "if Bob’s future is not determined, neither is all of his past."
    OK, yes Einstien and yes 2000 years ago; this insight was available; but outside of the theories of physics.
    Riemann geometry follows from operationalism.
    "the ‘mechanism’ that has access to the alternatives to accomplish that ‘interaction’ between them." Wait a minute, the mechanism that allows interaction between Bob and Alice is time or spacetime or NOT (i.e no interaction between them).
    Time dependence is discussed later and that is why I clearly use “ ‘mechanism’ ” and not “mechanism”, i.e. what I mean is correlation (but not just "common cause" classical correlation).
    I disagree, this is not the simple idea.
    Of course you must disagree since the idea is only simple if you do not outright reject my definitions! The simplicity and self-evident nature depends on new terminology being adopted during a paradigm change.
    Are there non-local phenomena in quantum physics?
    This has been discussed in great detail in the essay's last sections.
    "Without modal realism, non-locality violates Einstein-locality.. many physicists still opine that non-locality is merely a ‘really complicated’ correlation."
    Yep, we'll have to watch how theory and evidence gather
    We gathered enough to know this is a wrong attitude toward non-locality.
     if spacetime is nonorientable then there is no out there versus in there is there.
    You seem to misinterpret “out there” as outside of a subspace (say 10D bulk around a 3D string brane). I clearly use “out there” as opposed to “in my head”!

    Well, thank you for the thanks and the comments. In fact, many of your comments above reflect problems with the clarity of the essay that I have already detected. Some of my answers I can write fast because I have already rewritten those parts in a new version that simply talks about tautological derivation of QM and does not focus on the topic of the essay contest (i.e. what is wrong). So, indeed your comments are relevant.
    Sascha
    Yes this helps.
    But as you see from my comments; though I have struggled to understand, I have not fully understood.
    And if my confusion has help you focus on how to be more clear, glad to help.

    Just a few more comments.
    I'm beginning to understand your method and it seems good, a very good approach.
    I'm not qualified to judge the merit of your work; it's all new to me.
    But I am qualified to say whether I understand or not. I still don't fully understand.

    One point of misunderstanding between us which you might not have caught.
    I thought that you were arguing for QM locality.
    I think that you thought that I was arguing for QM locality.
    I personally think that QM nonlocality is pretty well demonstrated. I think now that that is your position as well.
    So I think we both misunderstood each others perspective on QM nonlocality.

    At this point, I'll try to digest what you've said and try to better understand your meaning.
    But since I am not completely daft; it my be premature to call Tautological modal realism a utterly simple idea.
    Unless we call it an utterly simple idea that is very difficult to understand.

    Nevertheless well done. I look forward to rereading your rewritten essay. thanks for assuming that we can (I can) at least begin to understand this important idea.

    vongehr
    Thank you.
    Yes - the locality-versus-nonlocality issue is extremely confused. That is the result of desperately trying to hold on to realism. By now, they have so much re-defined "realism" and "locality", nobody knows what "non-locality" actually refers to [not even the "experts"! - it is hard to get two of them to agree - I just had a fight with somebody who wanted to tell me that I must confuse with "separability" versus "local degrees of freedom" instead, as if without separability (~freedom), there are local degrees of freedom ("beables")]. There is no other way sometimes but cut your losses and do your own terminology or otherwise you will never get out of pure academic sophistication exercises.
    The simplicity of the simple idea: Einstein's accelerated elevator is simple, but of course, it is not simple before certain concepts were already accepted. Without even knowing gravitational fields for example, that idea would not make sense at all.
    I've given a lot of thought to your entry.
    Now let me try to paraphrase what you have said about Tautological Modal Realism for an intelligent 12 year old. Of course, I'm assuming that I pretty much understand your meaning.

    To a child:
    A picture of a flower is not a flower. It is some colors on a piece of paper. Furthermore, if three people paint the same flower they will use different colors, or look at the flower from the front versus back.

    Similarly, the world that I see is not the same as the world that a bee sees or an eagle sees. Our sense of sight is different in focus and in color. Furthermore, what you see today is not what you saw when you were a baby. A baby's eyes can see the color sensations; but a baby's mind cannot create the picture. Our mind has to learn to interpret the sights, sounds, smells, tastes and touches of our senses. Just as we can learn that something tastes good we must learn that a person isn't a cat or a hat.

    You laugh, but there is a famous true story called The Man Who Mistook His Wife For A Hat (by Oliver Sachs). You see this man was born blind. His eyes worked perfectly, his brain worked perfectly but there was a broken nerve between his eyes and brain. So one day, doctors fixed that broken nerve. But all he could see was fuzzy colors. He couldn't tell whether he was looking at a house or a tree or his wife and a cat. It was very frustrating, he had thought that he would be able to see immediately after his operation to fix that broken nerve.

    But the brain has to learn how to interpret the images that it sees or else it doesn't have any idea what it is looking at. Fortunately, most of us learn to see, hear, smell, taste and touch the things of the world directly. We learn so effortlessly as a baby that we think that the world that we see directly, the whole universe is actually the real universe.

    But the universe comes in many colors, and we do not see all of those colors. Night animals see differently than day animals. The world comes in many sounds, and we do not hear all of those sounds. In fact some animals like bats and dolphins hear sounds in such a powerful and specialized way that we could say that they see sounds. And so it is with all of our senses. As well their senses in the animal kingdom that humans don't even have.

    So our direct view of the world is put together by our brain and it is put together only with the sense data that we humans have. In other words, humans direct sense of reality is constructed by our brain and is missing a great deal of information that is contained in the real world. In fact it is missing most of the information contained in the real world. To be more specific, our idea or the world, of the universe is a very flawed idea that is very different than what the world is.

    So what is the real world, the universe. How can we define and understand it?
    As humans we have several methods of understanding and building a world view.
    Observation (or science), thinking (logic, reasoning, mathematics, philosophy), words (semantics, story telling), and other ways involving musics arts and speculations.
    And all of these world views or world descriptions are part of the total world.
    So we could start by saying that the universe is the sum total of all of the world as viewed by different modes of expression and different modes of being.
    A mode of expression could be a verbal mode versus a mathematical mode versus a musical mode.
    A mode of being could be a blind man versus a bat versus a physicists versus a fly.

    But as scientists and philosophers have thought and reasoned. Scientist and philosophers have realized that the total universe the totality of all world views as collected and summed by one man versus another man would be very different. Even if the too men were identicle, had the identicle ideas, the identicle scientific instruments, everything identicle except for one thing. If these two men were in a different location in space and time.

    Now the difference in spacetime location doesn't have to be big; but it is easier to see the principle if the difference in spacetime location is big enough. If difference in location is big enough, there are things that Bob can see that Alice cannot see and vice versa. But I'm not talking about the trivial things.

    What I am talking about is that according to the special theory of relativity, there are whole areas of the universe (including whole galaxies that can never be observed by Alice (but Bob can see) or by Bob (but Alice can see). Why is this so? How is it possible? It is possible because the speed of light is finite.

    And with a finite speed of light, their is information from in Alice's view of the universe that is not seen from Bob's view of the universe. So in a very real sense, Bob's universe and Alice's universe are not the same.

    Furthermore, if Bob is inside the event horizon of a black hole, then all the messages that he sends Alice will never reach Alice. And if Alice is inside the event horizon of a different black hole, then all the messages that she sends to Bob will never reach Bob. Now both Bob and Alice can see many of the same stars and galaxies that are outside of their black holes.

    But the point is that their universes are different even though both universes are defined as everything that they each can sense. So the direct realism, meaning everything that can be sensed by any instrument, of the universe is different for different individuals in the universe.

    How different? Well whole galaxies and superclusters may be missing. Even the laws of physics may be different. But these are just minor differences. There is a very fundamental problem.

    If Alice's world (inside A's black hole) can never communicate with Bob's world (inside B's black hole); if these two parts can never in any way under any circumstances communicate; then how can we even say that they are part of the same whole world, the same whole universe. Because being a whole implies that in some way the parts are connected, that information must flow from one part to another.

    If not, then we have just to totally separated parts, which happen to be two world views intersect and share a common part C (common). But that doesn't remove the problem. I still have part A that has no connection with B, and for sure C has no connection with D, and so on and so on. So what does it mean to have a totality that is the sum of parts that are wholly disconnected (i.e. no information, no sense or instrument is able detect the other part).

    Might we say that these are different worlds? That theses are different modes of reality, modes of worlds?
    Yes that makes sense.

    Now a tautology is something that is defined in such a way that by definition it is true.
    For example: X = Y and X = Z, therefore Y = Z.

    Now Tautological Modal Realism is by definition the sum of everything.
    The sum of all modes of sensing.
    The sum of all modes of understanding and modes of ideas.
    etc. etc.
    The sum of all modes of reality and all modes of worlds both possible and percieved

    Now why did wee add all of the possible worlds. Well because obviously, Bob or Alice understands the possibility of the other being real. Oh.

    Now what exactly does this mean? It means that if the universe is somehow the totality of everything, every possibility (i.e. Alice and Bob); that somehow the actuality of Bob or Alice must include the possibility of the other. And what this means is that the world of Bob or Alice can not be completely determined. There has to be some degree of freedom to Bob associated with the possibility of Alice or Zeno or... Or else the universe is not the totality of everything.

    And that may very well be that there are universes are not spacetime connected to our spacetime universe that is a continuun that includes you, me and the possibility of Alice and Bob and Zeno, etc... But let's just stick to our universe which is a spacetime continuum according to Einstein's theory of special relativity and general relativity.

    Now here, we bump into a problem of what is a continuum of spacetime and what does it mean that a universe is the full extend of such a spacetime continuum?

    Special relativity alone (but also with general relativity) along with the idea of Tautological modal realism leads one to the idea that there must be an uncertainty build into the universe. That even in special relativity alone, if Alice and Bob can see one another; the reality of Bob is influenced by things that are forever beyond the view of Bob and those Bob even with perfect information would not be able even in principle to access all of the physical causes that influence an event observed at Alice's location. And vice versa for Alice observing Bob.

    Thus special relativity alone without quantum mechanics demands a fundamental uncertainty in observation; that can never be overcome even in principle because there is a limit to the speed of light.

    So special relativity alone demands an uncertainty, and indeterminancy in the universe. Thus special relativity in addition to pointing toward general relativity also points to the fundamental need for some kind of quantum mechanics. In which uncertanty is necessary.

    End of my explanation of your idea for an intelligent 12 year old.

    So:
    Have I paraphrased you somewhat correctly?
    Do you Sascha see a logical path of development (mathematically speeking) to the Heisenberg uncertainty principles? I almost can see how. But I'd rather hear your more precise thinkings logic and answer; than my more fuzzy speculaation.

    vongehr
    Have I paraphrased you somewhat correctly?
    Sorry - no - this is all going way back into an assumption of naive realism and all that. Also: Getting Heisenberg uncertainty may neither be easy nor necessarily need QM. Before you become too enthusiastic: The Game of Live also has potentially evolving conscious systems and emergent relativity, but it is not QM! I could be a simulation inside GOL. I advertise a fundamental description where QM is natural, not having a derivation going from "I think therefore I am" to the fine structure constant.