This is my second entry to the contest, so I am getting a better sense of how things work. It seems that we often talk past each other in comments on others essays, so for those gracious enough to read and comment on my essay, I'd like to gently direct the blog:

The theme of my essay is simple: I suggest a way to understand quantum theory which can lead to physical theory, which avoids many paradoxes, and which does not suggest "It from Bit". The logical argument for the way to understand quantum theory can be summarized in a few points:

1) Probability is not real. Probability is a measure of our degree of knowledge which we assign to the outcome of an experiment. We do not assign probabilities to things or properties of things. Things do not have probabilities, outcomes do.

2) A wavefunction is a fancy type of probability and is therefore not real. More precisely, a wavefunction is an ordered list of all of the possible outcomes of an experiment and the probabilities that we have assigned to those outcomes. We express this ordered list as a vector. A wavefunction is thus a description of an experiment, not a thing. Things do not have wavefunctions, experiments do.

3) Coins, cats, silver ions, electrons, and systems are things, therefore do not have wavefunctions.

4) Coin tossing, certain types of controlled cat killing, and the deflecting of silver ions by oddly shaped magnets are experiments, therefore do have wavefunctions. In fact, these three experiments are isomorphic, so the same operator and wavefunctions could be used for each.

There are many consequences of this view, with two of the obvious ones being:

1) Wavefunction collapse is obvious. If the outcome of an experiment is known, of course we should make a new ordered list which assigns 1 to the known result and 0 to the others. It would be silly not to.

2) Schrodinger's Cat Experiment is not the least bit paradoxical: it is coin tossing. In the context of probability theory, |cat dead> does not refer to a state of the cat, it is an outcome of the experiment, and it would be better to write it in full as |"the event that the cat is found dead at end of the experiment">. It is an outcome state, an event, not an attribute of a cat.

(Too much has been written about this paradox, so to poke a bit of fun: The real paradoxical experiment is one where we put a bunch of physicists in a box and allow them to debate Schrodinger's Cat Paradox, and we measure the health of trees at the end of the experiment. The paradox is that the experiment returns an outcome of |tree found dead> far more often than reasonable observers would predict.)

So, I would be happy to receive any type of comments on the essay, but especially happy to receive comments directly related to the core argument.

Thanks for reading, Mark

Hello, Mark,

I liked your essay and your critique of Wheeler. I was also interested in the point about Mach: is he "responsible" for some of the problems in understanding reality by having introduced an unjustified categorial separation? If you look at my essay, you may see some thoughts about how matter/energy can be primitive on which I would welcome yours.

Best regards,

Joseph

    Mr. Feeley,

    This is a beautifully written essay, and in my opinion, it was the easiest one for me to understand of all the essays that have appeared so far.

    As an old decrepit realist, may I please make a self-serving comment about your fine essay? I believe that only unique exists. Your theoretical coin tossing machine could toss theoretical coins so that each tossed coin would land face up 100 percent of the time. I say no real unique machine could ever do so. May I point a tremulous finger toward the atomic clocks? Although they have been built to the highest of engineering standards, each clock still only records a unique time. Perfect synchronization can never physically be achieved.

      Joe, thanks for reading and for your very nice comments. You wrote a very similar nice comment about my essay last time.

      Since you were so gracious last time, and since you seem to read and comment on all essays as soon as they are posted, I actually read yours first as I was waiting for mine to be posted. I found it very enjoyable, and I agree with your realist perspective. I am probably at least as decrepit a realist as you. I only try to put forward some way to make some sense of physics given that realism.

      Thanks again, Mark

      Joe, thanks for reading.

      As to Mach: No, I think Mach was quite correct, and the category separation is justified. I think that the problems in understanding reality occurred later, with quantum theory: simply put, quantum theory incorrectly categorizes. Probability is an epistemological measure, and since wavefunctions are generalized probabilities, they are epistemological as well. Thus, things do not have probabilities, outcomes do. Things do not have wavefunctions, experiments do. I think this simple change allows us to understand both quantum theory and (to a lesser extent) reality better.

      As to your viewpoint that matter/energy are primitive: I certainly agree that something physical is more primitive than information. I think that it should be relatively obvious that information is information about something. However, I am inclined think that geometry is more primitive than matter/energy. Further to some of the ideas that you discuss, I also generally support the view that the continuum is ontologically more primitive than the discrete. Continuous systems can easily exhibit quantized behavior (eg. frequency) with the application of boundary conditions, but it seems a little more difficult for discrete ones to exhibit continuous behavior. In the context of continuous systems, energy is either defined as something proportional to amplitude squared (classical wave mechanics) or frequency (quantum mechanics). Since amplitude and frequency can both be seen as geometric quantities, I support an ontological structure that is continuum -> discrete, geometry -> energy/matter, and actually agree with part of Wheeler's contention in that I think the reality/information interface is necessarily discrete (ie. we only get discrete information about reality).

      Thanks, Mark

      Dear Mark Feeley,

      In a comment to Karl Coryat on your previous essay you remarked: "It would probably take at least another complete essay to argue against an entirely "it from bit" picture, so I can't really do the discussion justice, but I'll try nevertheless."

      Boy, have you delivered.

      Not only should all physics students be forced to write "Probability is not real" 500 times, but they should be forced to read your essay three or four times. This would, I believe, go quite a way toward clearing up current conceptual problems in physics.

      I completely agree with you that a belief in "magic" is the underlying basis of these problems, whether recognized by the believers or not.

      You mentioned that Edwin Jaynes redeveloped much of stochastic mechanics in terms of Shannon's information theory "and gave us a new understanding of entropy as an informational or epistemic concept rather than a thermodynamic one." And yet, as I quote in my technical endnotes, Jaynes said:

      "...a persistent failure to distinguish between the information entropy, which is a property of any probability distribution, and the experimental entropy of thermodynamics, which is instead a property of a thermodynamic state... [Many] authors failure to distinguish between these entirely different things [leads to] proving nonsense theorems."

      Your entire essay is important, but one of the most important lines is: "they will instantly recognize that an observable is a name for a type of experiment, not a property of some physical thing."

      This is what I was getting at in my essay when I said, "It is unclear what bits refer to: does spin have only two states, or is it that the direction of the apparatus' magnetic field forces spin into one of two states?"

      Your three line treatment of "collapse" is priceless!

      I would like to invite you to read my current essay, Gravity and the Nature of Information, and hope you will comment on it. Because you note that "the evidence offered by the equations positively suggests a physical world with wavelike features" I would also suggest you might enjoy my previous essay, The Nature of the Wave Function.

      Mark I think your essay is the best one in this contest so far for addressing the topics of this contest and the problems with physics. Thank you sincerely for writing this. It really should be required reading for all!

      Edwin Eugene Klingman

      Edwin, wow, thanks, that is very high praise.

      I think you have understood my point extremely well, and I am very glad, you pointed out the line regarding the nature of an observable. I actually think that one line highlights the central problem with the interpretation of quantum theory.

      I have not yet read your essay, but I'll read it next. Since you are in agreement with the ideas I have presented, I have no doubt that yours will reflect, and probably help confirm, a similar viewpoint. You are "spot on" with your consideration of spin. Just as a coin does not have a heads or tails state until the tossing experiment is done, so an electron need not have an up or down state until the Stern-Gerlach deflecting experiment is done. This is simply because heads and tails, and up and down are outcomes not properties.

      I appreciate your comments very much.

      Thanks, Mark

      Mark,

      It is a pleasantly readable and understandable essay, most of which I agree with. I do think probability is real though.

      One of the points I make frequently in these discussions is that physics simply models the normal view of time as a sequence of events by treating it as a measure of duration, when the underlaying fact is that it is action creating this change. To wit, it is not the earth traveling a fourth dimension from yesterday to tomorrow, but tomorrow becoming yesterday because the earth rotates. Consider this in terms of the infamous cat; in the future it is either dead or alive, but it is the actual occurrence of events which determines its fate.

      Now your argument against probability is that all circumstances leading any particular event exist and they will interact according to laws that will result in a determined outcome. The problem here is that there is no position prior to this event that all such input could be known. In order to know all input prior to the event, information of the input would have to travel faster than the actual input. Since much does travel as light, this would have to be even faster and if it were, then potential input could be traveling superluminously and the problem still exists. So while the laws governing any process are by definition, deterministic, the input cannot be known. There is no "God's eye view."

      While my own entry is decidedly perfunctory, one point I do try to make is that knowledge is inherently subjective and that since it is conveyed by energy, combining information will obscure and blur detail, losing information. So probability, ie. limited information, is fundamental to the very nature of information.

      Can't have your cake and eat it too.

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        • Post #11

        John, thanks for reading.

        I am pretty sure that probability is not real, and I think that people like Laplace, Bayes, de Finetti, and Jaynes, have made that case more convincingly than I can.

        I didn't make any comment on the nature of time in my essay at all, although I do intuitively with your position that it is a measure of relative change.

        As to infamous cats, I do not think there are any times when I can make a definite statement about the cat. I do an experiment when I put the unfortunate fellow in the box, namely looking at him to see if his tail moves. I do a second experiment identical to this when I open the box. Based on what I know about the conditions in the box (cyanide capsules, nuclear decay, and whatnot), I can make an estimate, a bet, as to what the result of the second experiment will be. At no time can I legitimately claim I know the state of a cat, initially, in between, or at the end. I can only ever know the result of an experiment, and I only do two of them.

        I definitely do not argue that "all circumstances leading to a particular event exist". I argue exactly the opposite: there is only one set of circumstance leading to an event. I argue for a very strict determinism, but one in which we do not know initial or intermediate conditions precisely so that we cannot know the future outcomes. Note that just because I do not know the causal sequence does not mean there is no causal sequence. This is precisely Jaynes' Mind Projection Fallacy. I agree there is no God's eye view, but this is only because there is not possible to have perfect information, even for this God person. Thus, just because God does not know the causal sequence does not imply that there is no causal sequence.

        I didn't exactly follow your point about superluminous transport of information. I argue that quantum theory is a theory of experiments, not a physical theory, and thus it makes no sense to speak of QM as either local or non-local - it is entirely epistemic. Therefore the locality or non-locality of QM is irrelevant to any question of the speed of information transfer. Nothing at all about the physical world can be concluded from any apparent locality or non-locality of QM.

        Too bad about the cake thing though, I quite like cake and I like to share it too.

        Thanks very much for reading and commenting. Mark

        Mark,

        I guess my argument in a nutshell is that while the laws determining an outcome are, by definition, deterministic, there is no way to know all the input, from any frame, so it is not pre-determined, ie. fated.

        The point about time is that while we experience it as a series of circumstances, from past to future, that which is past has been determined, while that which is future hasn't yet been, so when we treat this vector as fundamental, we go from a determined state to an indeterminate state and end up in multiworlds. If we look at it from the other direction, the indeterminate state becoming a determined state, it makes much more sense.

        Before the race, there are ten winners, but after it, only one.

        John, I think I can lay out a way that your understanding the vector of time as a series of circumstances is consistent with my interpretation of QM in a sensible way.

        I agree with the assumptions of your first sentence, but not the conclusion. I argue that the laws determining an outcome are by definition deterministic, and there is no way to know all the input. So far we agree. Where we differ is in the last clause. I argue that this means the outcome is indeed determined, and is indeed fated, but we do not know, and cannot know, that predetermined outcome or fate in advance.

        I think you are conceiving of your vector of time as a series of circumstance, rather than a dimension, which I can accept. But in these terms then, I think there are two such vectors, one is the "actual" vector, in other words, the predetermined or fated vector, the other is our imperfect guess at this vector.

        In fact in quantum theory, we make formally vectors pointing at each possible outcome, and assign probabilities to them and this vector with probability components is the wavefunction in a Hilbert space.

        Thus, in your race example, we make 10 vectors, one pointing to each of your runners in the race. Formally we make these outcome vectors orthonormal. We assign a probability (expressed as a root) to each runner. To project the outcome of the race, we give a magnitude equal to the root of the probability for each outcome to a vector in the corresponding direction, and add the ten vectors. Since all the probabilities squared add to 1, this gives us a unit vector. This vector is the wavefunction in Hilbert space. The wavefunction thus describes the projected outcome for the whole race, not the state of a runner.

        In this picture, there is an actual sequence, which I am understanding as your vector of time, which results in an actual outcome of the race. Then there is a second vector, which is a probability weighted vector pointing to possible outcomes, which is the wavefunction. Since it is a generalized probability, this second vector is not real, and not fundamental.

        I hope this captures where we agree and disagree. I can certainly agree with your notion of time, but I think I have described how it can be understood in a way consistent with my interpretation of quantum theory.

        Mark

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        • Post #14

        Mark,

        The difference seems to be between determined and pre-determined. Necessarily everything that does happen is determined, but prior to that, the factors which will do the actual determining and not just speculate about it, are not yet interacting. Now a spectator can, given sufficient information, make a fairly educated guess as to the outcome of a particular event in controlled circumstances, but that can only account for the expected.

        So I would again argue that while we can predict an outcome and conclude after the event that the result was determined by the course of events, that prior to the event, neither the actual factors involved, nor any speculative position can either theoretically or effectively know the actual course of events and that this amounts to a lack of pre-determination. Not to be confused with the fact that some sequence of events will emerge and be evident after the fact.

        To suppose a "fated vector" is to suppose some form of "fore-knowledge" by the system as a whole and that goes back to the subjective nature of knowledge, as opposed to our top down tendency to see ourselves as objective.

        John, (it says anonymous, but I assume you've been hit by the time out on login).

        This is an interesting discussion which offers some insight into both information/reality and deterministic/non-deterministic. I will concede (and I hope you do as well) that both arguments can be used to fit the empirical evidence. However, the choice between the two is not simply a matter of taste. The choice speaks to the entire nature of physical law.

        You argue (I hope I paraphrase correctly):

        1) That we are able to determine the actual state of physical things in the present. A sequence of events up to the present may be determined by plotting a trajectory of such states through a state space.

        2) Some events or outcomes are fundamentally indeterminate. That is, there are some fundamentally stochastic (= somehow inherently "random" or somehow "uncaused") events. Thus, we are unable to predict future outcomes.

        I argue:

        1) That all events are entirely predetermined (or fated if you will). This is an assumption about the nature of all physical law - a character of the ontological domain.

        2) That we (and "we" emphatically includes God) may never know a physical state. We may only know the result of experiments. Since we cannot know even a single physical state, we cannot know a trajectory in state space, even in the past. Since we can never know a current state or past trajectory, we can never predict with certainty the outcomes of future experiments, even in the context of deterministic evolution. This is a statement about what we can know and what we can predict - a character of the epistemic domain.

        Your argument can not be rejected out of hand. Indeed, it is essentially the one which is at the heart of orthodox QM, and which has now had about a century of primacy. However, I think it leads to many of the paradoxes and interpretational difficulties of QM, which have not been resolved in that century.

        I propose to resolve many of those issues by assigning probability, wavefunctions, and any other predictive tool, to the epistemic domain, the domain of information, where they rightfully belong, and "purifying" the ontological domain, the domain of reality, so that it is entirely governed by deterministic physical law. I do not think that determinism implies fore-knowledge at all. Knowledge is the epistemic domain, not the ontological. Predetermined and predictable do not mean the same thing. An event may be predetermined (a characterization of events in the ontological domain) but yet be unpredictable (a characterization of events in the epistemic domain).

        I could be be wrong, and as I said, both approaches can fit the evidence. I just think that after a 100 years of relative futility in resolving quantum paradoxes, we might try a different approach.

        Nice discussion. Thanks for engaging.

        Regards, Mark

        Mark,

        Actually it would be a no to both paraphrases. My entry might explain why on the first. ie the subjectivity of knowledge. As for the second, I accept cause.

        I'm willing to agree my point is epistemic, but that does raise the issue of what ontological really is. For one thing, the concept of pre-determination would essentially be meaningless, because there is no concept of past and future, only present action. Cause is simply that the energy is conserved.

        Dear Mark Feeley,

        I have down loaded your essay and soon post my comments on it. Meanwhile, please, go through my essay and post your comments.

        Regards and good luck in the contest.

        Sreenath BN.

        http://fqxi.org/community/forum/topic/1827

        Mark,

        "... a great many theoretical physicists believe in magic and not physical law." WOW, what a great way to begin an essay of what I found to be a kindred sprit! I trust you will find my coin-in-cup experiment of value for it supports your position of causality.

        I believe you will find my cause and effect analysis of the four forces of keen interest. The findings as presented in my essay have led me to examine how causality unifies gravity with the strong, weak, and electromagnetic forces as one super-deterministc force, see:

        http://fqxi.org/community/forum/topic/1809

        Best wishes,

        Manuel

        Hi Mark,

        Nicely written essay that flows well. Passionate too, which is nice to see here. s I especially like that you've concluded it "wrong and dangerous to assume that information is fundamental". I think that It and Bit are either likely equally fundamental or reality is more fundamental. Hopefully you will take a look at my essay too, so we may discuss any common ground (or differences for that matter).

        Kind regards,

        Antony

        Hi Mark,

        I agree that '' ''It from Bit'' is simply not [Wheelers] finest hour''. However, I do not agree with your statement that '' ''It'' does not derive from ''Bit''. ''Bit'' manifestly derives from ''It''.''

        If there would be only a single charged particle in the entire universe, then it wouldn't be able to express its charge in interactions. Since it in that case it cannot be charged itself, charge, or any property, for that matter, must be something which is shared by particles, something which only exists, is expressed and preserved within their interactions. I think that the idea ''so simple ... that when we grasp it, we will all say to each other, how could it have been otherwise?'' is the quite obvious proposition that in a universe which creates itself out of nothing, fundamental particles (its), their properties, are as much the cause as the effect of their interactions, of the (exchange of) bits, so you obviously cannot have one without the other.

        Regards, Anton

          Anton,

          You raise some interesting and difficult points, which I will attempt to deal with.

          Actually, I think that the first point so is not difficult: I think information is evidently information about something, of Bit is indeed manifestly from It.

          Your other points are more subtle so much better to discuss.

          First of all, I take Mach much more seriously than Wheeler. Per the quote I included in my essay, Mach says that the best science can do is be the most economical abstract expression of facts. Taken seriously, this means that science cannot tell us what "is". It can only arrange the apparent facts nicely. To arrange our facts, we build models, mathematical pictures of particles and fields and forces and energies and whatnot. Per Mach, we cannot claim any of these things exist, although this emphatically does not imply something does not exist or reality is not fundamental. All we can do is build models, usually with some parameters, and a particle with a parameter of charge is such a model. Thus, when we speak of "a particle" or "a wave", we are really speaking of "the idea of a particle" and "the idea of a wave". (I admit that these steers dangerously close to Wheeler, but Wheeler goes too far by claiming that the idea of a particle "is" the particle or is more fundamental than whatever is that is real). If that is acknowledged, then the idea of a particle necessarily includes both its causes and effects. So, if we are talking about the idea of a particle then I agree with you, they are as much cause as effect of their interactions. However, I am inclined to think that Mach was more perceptive than most of us, and therefore we cannot claim that particles (or waves or anything) exist, so if your argument rests on such a claim, then it must fail.

          Overall, I think the idea that cause is fundamental is a much stronger logical position from which to build physics than the idea that particles with charge are fundamental. If particles are as much cause as effect of their interactions, I suggest this points to a weakness of the particle model, rather than an invalidation of the principle of cause.

          To get more clearly at the point about causality, given that I claim not to know what exists: I simply argue that it is the most economical to assume it. There are (at least) two types of models that we make in physics. The first are "physical" or ontological models: models which attempt to describe the world in some way. Most of our models are this type, Newtonian theory, Maxwell's electromagnetism, Einstein's gravity etc. They all assume a certain model structure, the existence of physical "things of some type, along with a strict determinism and causality. On the other hand, I have argued that quantum mechanics, similar to probability theory, is not one of these, and that it is a theory of experiments. Quantum mechanics actually describes the process of doing experiments which unknown outcomes, nothing more. It is an epistemic model, and it is not in any way a physical theory, therefore cannot say anything about physical theory. Physical content only enters by the probabilities which we assign various outcomes. We assign the probabilities and equation of by which we guess they might evolve, they are not inherent parts of the theory.

          A somewhat more nuanced version of my argument is that I thing we are will achieve Mach's goal of the most economical abstract expression of facts if we continue to assume ontological models with a strict determinism, that is, where cause is fundamental. Furthermore, with QM properly understood as an epistemic theory not an ontological one, we have no barriers to continue to assume such ontological determinism.

          Sort of long winded, but you raise difficult points, so I had a go.

          Thanks for reading and thanks for opening a discussion, Mark

          Mark,

          I enjoyed your essay and agree with most points.Your magic metaphor, I attribute to the narcissism of humans.

          "Just as the ancient painters used pigments to create representations

          of the reality they saw,we use mathematics to create representations of the reality we see."

          I like your comparison.