Reductionist Doubts by Julian Barbour

Julian

Are you agree with my abstract?

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

Whenever I see Dr Julian Barbour or Dr Laurent Nottale's name, I am pleased and excited. I see any of them as the greatest humans in our science history whereas Einstein is nothing but a funny God. Sorry for those believers, I offended your God. It is OK, you God's believers can ask HIS officers to delete my comment.

Julian Barbour,

Your friend Lee Smolin does not seem to be indoctrinated in the constant-speed-of-light religion:

http://www.amazon.com/Trouble-Physics-String-Theory-Science/dp/0618551050

Lee Smolin, The Trouble With Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next, p. 226: "Einstein's special theory of relativity is based on two postulates: One is the relativity of motion, and the second is the constancy and universality of the speed of light. Could the first postulate be true and the other false? If that was not possible, Einstein would not have had to make two postulates. But I don't think many people realized until recently that you could have a consistent theory in which you changed only the second postulate."

http://www.fqxi.org/community/articles/display/148

"Many physicists argue that time is an illusion. Lee Smolin begs to differ. (...) Smolin wishes to hold on to the reality of time. But to do so, he must overcome a major hurdle: General and special relativity seem to imply the opposite. In the classical Newtonian view, physics operated according to the ticking of an invisible universal clock. But Einstein threw out that master clock when, in his theory of special relativity, he argued that no two events are truly simultaneous unless they are causally related. If simultaneity - the notion of "now" - is relative, the universal clock must be a fiction, and time itself a proxy for the movement and change of objects in the universe. Time is literally written out of the equation. Although he has spent much of his career exploring the facets of a "timeless" universe, Smolin has become convinced that this is "deeply wrong," he says."

I have the impression that high-ranking Einsteinians have secretly abandoned Divine Albert's Divine Theory long time ago. Is that true?

Pentcho Valev pvalev@yahoo.com

Julian

By definition (ie it is the only way physical reality can occur), the sequence of physical existence only occurs in 'one direction' and once. That is, any occurrence which has the appearance of oscillation or reversal, is a repetition of a previously existent state (ie present). Though in actual fact, it is highly unlikely to be even a repetition; it just appears so to us when viewed at a higher level of differentiation than that which actually occurs.

Similarly by definition, what constitutes the physically existent state of any given present, must be a function of the immediately previous one, because physical influence cannot 'jump' physical circumstance (and neither can a non-existent state have influence). Furthermore, of those possibilities, that which was the cause must have been immediately spatially adjacent to what subsequently occurred, because, again, physical influence cannot 'jump' circumstance.

The explanation as to how and why any given different state occurred, must ultimately be explainable as a function of the lowest level of that which caused it (ie the previous state). In any given circumstance, cause must ultimately be traceable to, and be a function of, the fundamental components of the circumstance involved.

Finally, these rules apply to all physical existence. There cannot be a situation whereby some phenomenon is deemed to have some physical effect, but have no physical existence of its own.

So the crux of the problem is: what, generically, constitutes a physically existent state, ie physical reality-that which exists as at any given point in time, and complies with these rules.

Having said all that, there is nothing wrong with applying a different approach as it might spark an idea. But this must then not lead to hypotheses which contravene the way in which physical reality occurs.

Paul

Dear Julian,

I thoroughly enjoyed reading your essay. You write as well as you think. I have a few questions/remarks.

1. To what extent are shape dynamics and best matching dimension-specific? I ask this for three reasons. The first is because I wonder if dimension 4 is "selected for" by having special properties in this regard. The second is because certain theories, such as string theory, involve different numbers of dimensions, and it would be interesting to know how universal these ideas are. The third is because metric recovery from a different type of structure; namely, causal structure, is very different in dimension 4 than in dimension 3, for instance.

2. You mention matter-energy briefly in your endnote number 8, but just to be sure, do you regard matter as "part of" the conformal structure at the most fundamental level, or as something that "lives in" and "interacts with" the conformal structure?

3. In one of your references to The End of Time (which I have not read), you imply that time is an illusion arising from large quantum amplitudes of "time capsules." Do you regard causality also as an illusion, and how (if at all) do you distinguish between the two concepts?

4. I am curious about your general opinion of order theory in fundamental physics. The reason I ask is because the continuum is an order-theoretic concept, and you seem to comfortable with manifolds over the continuum, but seem to abstain from time/causal order as a fundamental concept, at least at the quantum level. Now, personally, I have it the other way around. Coming from a math background, and working mostly with complex manifolds and algebraic schemes, I find it very hard to believe that anything so fantastically uniform is physical at the most fundamental level. On the other hand, the idea of binary relations seems so primitive and basic to all observation that it seems like the most natural place to start. I discuss this, among other things, in my own essay:

On the Foundational Assumptions of Modern Physics

Just to be clear, I agree with you that holism is necessary, but I suspect it arises purely at the quantum level. Also, I think matter-energy and spacetime are ways of talking about aspects of a single structure at the classical level. Finally, the "superspace" in my view has the same type of local structure as its constituent universes, so "quantization" is an iteration of structure in a sense.

Anyway, I am too early in my physics learning curve to be committed to any particular theory, and the ideas you present here require some serious thought on my part. Take care,

Ben Dribus

Thanks Julian for another thought provoking essay! Your writing always makes me reflect. You're right that shape dynamics brings out the holistic nature of general relativity. The same holism is also manifest in the non-local nature of observables in GR and the holographic principle. Maybe this is not a coincidence?

Dear Dr Barbour,

Thanks for your thinking in different angles. You opened a new door in my own thinking by introducing SD, it widenes the perceptions that I had untill now. In "THE CONSCIOUSNESS CONNECTION" I also questioned reductionism and favoured "emergence" (i also referred to your work).

The first question I have is about page 3 : you say "If the universe is spatially infinite, the answer is equivocal" (closed up), this looks like the center of the infinite circle that is everywhere, where it becomes a paradox, because the center is a point a singulairity. How do you see that ?

The second one : page 5: "three particles pictured as dots on an infinite sheet of grid paper, then two coordinates dtermine the position of each" I wonder what coordinates that may be on an infinite grid, my perception is that the three points may be on any point on this grid and it is not possible to point out coordinates toward the limits of the grid becuase it is infinite, the points can only be coordinated in relation with themselves, but perhaps you meant to say that.

"Terms of Complete Shapes of the Universe" (page 8), is a statement that paralels my perceptions of the alpha-probability in Total Simultaneity (the harbour of the "immense multitude", only with applying SD, it becomes more causal understandable. Imagine the TS as the singulairity with the infinite radius where there is an infinity of angles.(see also question one).

"Even the times themselves are in a real sense created by the universe", here you are I think contradicting your former thinking, you are right when one accepts that the universe is a creation of consciousness and so again non existing as a measurable dimension, the objective illusion of time I declare by decoherence between the cutting Subjective Simultaneity Spheres forming a foam of circles with objective simultaneity.

By the way I liked very much your PLATONIA.

best regards

Wilhelmus

Julian

"For Paul Reed, I think you make rather conservative assumptions about "the way in which physical reality works".

There are two knowns about physical existence: a) it is independent of sensory detection, b) there is alteration. Therefore, it is sequence. And the key feature of sequence is that only one state in any given sequence can occur at a time. Because the predecessor must cease in order that the successor can occur. This also governs what can potentially be a cause, both in terms of the sequence of existence and spatial position. The point about traceability to the smallest denominator is a logical truism.

So there is nothing conservative about this, it is determined by physical reality, of which we are a part, and an avoidance of metaphysical concepts which have no physical correspondence. However, it is easy to say all this. The real question being: what constitutes a physically existent state as at any given point in time, ie physical reality-that which exists (there may be more than one type). Timing being the method whereby occurrence can be differentiated until one discerns what occurred at a point in time, which, practically, is probably impossible for us to achieve. Certainly at present the tendency is to refer to some physical state as having been existent when in fact it comprises more than one (ie there is alteration within the 'state).

Paul

Leading philosophers and physicists (FQXi members among them) go even further: they reject special relativity, preserve Einstein's 1905 precious light postulate and restore absolute simultaneity (Orwell would call this "triplethink"):

http://www.amazon.com/Relativity-Simultaneity-Routledge-Contemporary-Philosophy/dp/0415701740

Einstein, Relativity and Absolute Simultaneity (Routledge Studies in Contemporary Philosophy): "Einstein, Relativity and Absolute Simultaneity is an anthology of original essays by an international team of leading philosophers and physicists who have come together to reassess the contemporary paradigm of the relativistic concept of time. A great deal has changed since 1905 when Einstein proposed his Special Theory of Relativity, and this book offers a fresh reassessment of Special Relativity's relativistic concept of time in terms of epistemology, metaphysics, and physics. (...) Unfortunately for Einstein's Special Theory, however, its epistemological and ontological assumptions are now seen to be questionable, unjustified, false, perhaps even illogical."

Pentcho Valev pvalev@yahoo.com

Dear Julian

Another clear, well written essay. I have always looked at machian principles and SD with great enthusiasm and the essay makes it very accesible. The idea of generating the background (space,time) upon the behaviour of their ''inhabitants'' fascinates me. As I told you before, I plan to study SD deeply and try to find the origin of the best-matching procedure (maybe by using category theory?).

''Instead of thinking of particles in space and time, we should perhaps be thinking in terms of complete shapes of the universe''

We arrive at the importance of shapes by questioning:'' what is time, what is space?'' and giving a meaning to them by observation. More questioning on what is time and what is space could lead to something even bigger that could maybe have SD as a part. This is what I argue in my essay (that I showed you as a draft via email. here´s the final version Absolute or Relative Motion...or Something Else?), and it´s something I´ve been thinking.

Good luck in the competition!

Best Regards,

Daniel Wagner

Hello Mr Barbour,

I found your essays very intresting. We search the answers. The universal spirituality like a torch of extrapolations. The reductionism for me is more complex. The trinity that said is relevant considering the fractal form the mai central sphere. But the complexity after this 1 and 3 is so important. The system is finite and precise, so it implies a specific serie , similar for the quantum scale and the cosmological scale. This number is very relevant. The main codes are inside these main central spheres, with their correlated volumes. This ultim fractal permits also the cretaion of all others forms. Your dynamics of sphapes are relevant when the finite groups are inserted. The newtonian mecanic and the Borhian interpretation are very relevant when the rotations are proprotional with mass. The unification of the SR and GR is explained in this line of reasoning.The duration is implied by the rotations of spheres.The time is so a pure correlated duration. Irreversible in its pure generality. The machian principle is relevant, your extrapolations also. My equations help for the universal rotation around the central sphere. That said the Universal sphere and this central sphere in my line of reasoning does not turn. So the rotation of the Universe of Godel is not logic in its generality.Only the intrinsic spheres turn.So the quantum spheres and the cosmological spheres. See that more a sphere turns, less is its mass.its volume also is correlated. That's why the finite groups are essential for the uniqueness serie. Like for the quantization of the mass. In this logic, the SR and the GR are unified.the light turns in opposite sense than mass.

They turn so they are Mr Barbour ! the inertie dances with my equations if and only if the serie is finite considering the ultim fractal.

See that this fractal is universal, so the universal sphere is a foto of our quantum uniqueness. It is important consideringt he Machian principle and the entropical principle in a closed evolutive space time. See that the isotropical and homogene space time(the sphere) is essential.

The coherences appear easily when the groups are finite for the quantization.

I ish you good luck, it is abeautiful essay.

ps the fractal permits to create also all the forms and shapes.because the lattices disappear in the perfect contact....

Regards

JB:

Somehow, your essay seems related to my model, (in End Notes of To Seek Unknown Shores

聽聽 http://fqxi.org/community/forum/topic/1409

I am trying to imagine the distal vertex of a tetrahedron that communicates with the central point of sphere contained within the solid angle of the tetrahedron such that the sphere is always tangent to the tetrahedral face. It is a naive attempt to combine motion AND growth from microscopic to macroscopic dimensions.

Perhaps you can destroy the idea so that I might really retire.. Thank You.

Your writing is lucid.

Hi Julian,

Thanks for yet another well-written essay. You may be interested to read some of Eddington's Fundamental Theory. There are some similarities to your approach.

Nevertheless, I have to say I was a bit surprised by some of your assertions regarding reductionism. I think there is a subtle but important distinction that appears to have been muddled in several of the essays that have been critical of reductionism and that is the difference between reductionism as a method for investigating science and reductionism (or "constructionism" as P.W. Andersen called it) as an actual causal "structure" to the universe.

Certainly holistic approaches are indeed useful and even reductionism itself does not deny that new features will appear at higher levels of complexity. But the holistic approaches still require knowledge of the fact that there *are* parts to begin with and thus must mean that some individual understanding of those parts is a prerequisite to understanding the whole. By dint of the fact that something possesses non-uniformity, which it must if it is to be understood as *having* parts to begin with, requires some recognition of those parts as individual features. Thus it would seem reductionism is *required* to some extent for an understanding of anything other than an utterly featureless structure.

So, for instance, in your example of the triangle from shape dynamics, the concept of "shape" still requires knowledge of the concept of angles. To a large extent, this is still reductionism. Thus, while the universe itself may not be reductionist in its structure, I fail to see how we can make sense of it outside of a reductionist framework which is much broader than you make it out to be. Honestly, I really don't see how any of the shape dynamics arguments point to any serious flaws in reductionism itself unless one takes a seriously narrow definition of it that is completely inconsistent with the way it has been used over the years.

Incidentally, many of the "failures" of reductionism that people like to point to (e.g. you mentioned some issues with general relativity) may simply be that these discoveries (like general relativity) are not universally applicable (incidentally, with regard to shape dynamics, I fail to see how it is all that different from a block universe, not to mention the fact that it seems as if the changes still need to be relative to *something* though heaven knows what that is).

Regarding the history of reductionism, I also don't see how Newton's notion of absolute space "introduced" reductionism. That seems like a bit of "backward causation" from the shape dynamics argument about triangles. The truth of the matter is that reductionism as a method for carrying out the scientific method was developed by a number of people over a span over nearly 200 years.

Sorry to sound overly harsh. I think there are certainly some interesting ideas to be explored here (including one that I will e-mail you about concerning the relationship between distance and angle), but I think my biggest objection is that it seems that reductionism has been mis-characterized. As one anonymous poster said elsewhere on this site, "In a serious sense anti-reductionism is a straw man. Practically, realistically, there's no other way to do experimental science except analytically."

Again, sorry to sound so harsh. But where would we be without friendly disagreements, eh? Perhaps we'll get to do one of those mock debates at the next conference with you (and George Ellis and others...) on the pro-reductionist side and me (lonely old me...) on the anti-reductionist side.

Cheers,

Ian

Julian

Indeed it is difference. Physical reality occurs differently, ie when one is compared with another then difference is identifiable, and hence we know there is alteration. In the circumstance of physical existence, any given sequence can only be linear because the predecessor must cease to exist. There can only be one physically existent state within the sequence at a time. Any form of recombining, oscillation or whatever is really a re-occurrence of a previous existent state (though I think the complexity is such that this could never occur, it is just that from a higher level of differentiation it appears that way).

The analogy is a film. It has the appearance of constant movement, but ultimately there is a state of non-movement. This is the importance of timing (your favourite subject!). Because difference involves: 1) substance (ie what it was), 2) order (ie order of occurrence), 3) frequency (ie the rate at which differences occur). Timing is concerned with the latter. In other words. if we had a timing system with a unit of time which was equivalent to the fastest change in existence, then what occured could be differentiated to the level where there is no form of change. Which is what is physically existent, as it cannot involve change as that constitutes more than one existent state. Timing is concerned with the rate at which change occurs, it is not a feature of any given state of physical reality.

Take an elementary particle spinning. What constitutes physical reality? The particle-no because it is in a variety of physical states. One has to identify one of them. So is it half a spin, a whole spin, etc? No, because that involves more than one physically existent state. The answer involves isolating the smallest degree of spatial alteration possible. Take the life-cycle of a leaf. Ontologically, it is incorrect to refer to the entity as leaf, thereby implying it is the same, but altering. It only appears to be the same at the level of differentiation we are capable of. In fact, it is a different physical reality as every given point in time in the sequence, it just maintains certain superficial physical attributes which we ascribe to leaf, and only one of those occurs at a time.

Paul

Julian,

I am suspecting that the angle you "measure" in ADM correlates somehow to a Lorentz Rotation angle? Recall that a Lorentz boost can be represented as a bonified rotation in the information space of Dirac. Does ADM build the "information space" of Einstein that provides the ultimate in a physical spatial scaling w/ "a measured Lorentz angle value" for each physical object possesing mass and having a rest frame to make measures within? If so, this sounds like the information we receive when we multiply by a complex #. Isn't this the information attained by conformal QED? ADS/CFT stuff with Alpha being the 5D symmetry having the 4D QFT "shapes" occupying a bounding surface?

Your analogy of the Alpha as the most uniform angle space yearned for by all different angle spaces (well you may not have exactly stated this ... ad lib by me here) may imply that the angle space of the ADS version of a QFT "desires" to become part of the 5 Dimentional informational space but has asymmetrically been broken off and given a series of angle measures that "precisely measure the asymmetric break-up" (maybe encoded in DNA for a "life" shape?)... like a conciousness in birth being the asymmetrical parting from a structure having a complete symmetry (like point symmetry of the electron. Hmmm, this may imply that the quantum field is created by nothing more then a correlation between the asymmetric "yearning - a projection on to Alpha" that drives all other shapes to entropically become more in line with the symmetric Alpha (an S matrix with a mission!) ... thus ... all shapes contain paths (maybe similar to the Feynman decision paths) that lead them them back to occupy the Alpha symmetry once again... ?

Afterall ... in ADM a living thing would have a shape space ... and like all shapes ...

My most enjoyable read, Thank you,

Tony

Dear Julian Barbour,

thank you very much for this essay. It does very clearly set out your ideas and the ideas of other that have been the foundation for them. Like your previous essays, it is accessible to non specialists, very well crafted and relevant to the essay question. I am sure there is still more I can learn from it. It is another fine essay.

You wrote "Using grand philosophical terms, the gap between epistemology - what can be observed - and ontology - what is assumed to exist - should be as small as possible. Ideally, there should be no gap at all....." That is where our views necessarily diverge. As I regard the observed output of data processing to be distinct from what existed unobserved as the source of the data.

Thank you once again for giving some time to discuss you work on your blog thread and your replies here. Good luck in the competition.