George,

You wrote in reply to Edwin & Ben: "The key issue you are both raising might be that in coarse graining physics one also needs a coarse graining of time to get the effective higher level laws. This certainly needs thinking about and I am not aware of much work on this."

I know Edwin eschews multiple dimensions; however, mathematical expressions of higher level laws, even in higher dimensions, do not forbid nonlocal causality in a finite space. That is, a closed logical judgment (mathematics) is 1 to 1 correspondent with a local physical result in the experimenter's measure space.

This dichotomy -- between the local measure space of infinite range and the nonlocal domain of finite range -- led me to realize that Joy Christian's proposal using dichotomous variables eliminates the local-global distinction. That makes it fully relativistic ("all physics is local") and angle preserving in its application of topological orientability.

Point is, that the general relativity interpretation of a universe finite in time and unbounded in space suffers no loss of generality as a universe finite in space and unbounded in time. This latter interpretation, though, fully embraces Minkowski space-time dynamics without ever having to refer to time as a physical phenomenon. Top-down causation is therefore continuous and locally real; continuous measurement functions are constrained by space-time topology (generalized geometry). I think this is consistent with your evolving block universe of spacetime evolution with no preferred surfaces.

Best,

Tom

Yuri

"We live in a universe that was born from a previous universe"

- so how did that previous universe come about?

Actually this has nothing to do with the topic of this thread. Your quote "we live in a universe which creates itself out of nothing," was not my statement, it was made by Anton. If you disagree please take it up with Anton on his thread.

Dear George,

Just a quick note to thank you for recommending Arthur Eddington's marvelous book 'The Nature of the Physical World.' I'm reading it now and enjoying it immensely. Having also just recently read Poincare's 'The Value of Science,' dating from 1913, it's fascinating to observe the evolution of thinking on many topics still of keen interest and still very much in a state of flux even today. It seems very much in keeping with the theme of this essay competition to observe the flow and, dare I say, "crystallization" (or lack thereof) of thinking on these topics over the past century.

Fwiw, I'm personally convinced that we're currently living through and participating in what Thomas S. Kuhn would describe as a "crisis state" in physics. Would you agree? And if so, do you think that this is generally recognized and/or accepted in the wider physics community? I don't read or hear others talking in these terms, but I believe the evidence for it is abundantly clear; it's virtually a classic case, in my view. Exciting (and occasionally frustrating) times to witness.

Regardless, thank you again for the book recommendation.

jcns

    Hi jcns

    glad you are enjoying it. He was a great pioneer in astrophysics and cosmology, with a wonderful power of explanation. His book on the internal constitution of stars is still great reading, even though it was written before nuclear physics was understood. Physicists of his epoch did not deride philosophy, they realised its role as an underpinning to physical thought and took it seriously.

    Yes I do think there is a crisis in physics - but not all of it! One can get a very wrong impression of physics if you only read some of the over-hyped theoretical physics stuff, much of which seems in danger of losing touch with reality (for some people, models are more real than reality). But a vast amount of physics is absolutely solid, relating theory to marvellous experiments in materials science/solid state physics, nanophysics, quantum optics, biophysics, and so on - Nature Physics is full of the stuff, much of it very exciting. It is on the theoretical side,and in particular in relation to cosmology, where more and more extravagant hypotheses are being proposed with very little concern for usual constraints and/or for testability. "Phantom matter" and dark energy theories with p/rho < -1 are examples of the first; multiverses and theories of creation of the universe out of nothing are examples of the second. But physics has a great capacity for self-correction, and I think the more extravagant ideas will fade away and turn out to be ephemeral, as these ideas are tested and evaluated by the physics community in the long term, who hopefully will start to take philosophical issues seriously again. And I think the idea of top-down causation will gain traction and not fade away, even though it has so little support in the physics community at present. Ernst Mach and Dennis Sciama were early proponents of the idea, even if they did not call it such; present theories of the origin of the arrow of time are also of this kind; and it is starting to gain traction is some areas of astronomy, under the name "environmental effects". The exciting part is that it may help understand foundational quantum physics issues. Watch this space - but with a bit of patience!

    By the way, you quote Kuhn - have you read any Imre Lakatos? He has a more developed view of how changes of scientific research programs take place.

    George

    So it's previous universes all the way down. Are you claiming any of this is testable? Is this supposed to be science, or do you claim science does not need observations? How many universes back do you claim to prove exist, by some kind of observation - and what is the nature of the observation?

    Actually Penrose got there first: see his book Cycles of Time.

    I don't plan to read your correspondence with Weinberg, despite your demand that I do so.

    George,

    How do you explain the bottoms-up fixation? Do you think it is a cultural thing or universal? What about same-level mode as efficient and circular, the way some of your colleagues characterize it.

    I can see that the fixation you describe could explain thinking regarding many issues in physics including the nature of gravity, which I deal with.

    Jim

      Hi George,

      I regret to say that I have not yet had the pleasure of reading Lakatos; thank you for pointing me toward his work. I see that several of his works are available for purchase on the internet. Could you recommend a good, not-too-technical entry point for making his acquaintance?

      I've long admired Kuhn's 'The Structure of Scientific Revolutions,' and see evidence of his "crisis state" in some aspects of physics. Lee Smolin touched on some of this in 'The Trouble With Physics.' Speaking of which, I've heard from a reliable source that Smolin plans to publish at least one new book on the nature of time later this year. I hope so.

      Thank you for helping broaden my horizons.

      jcns

      Hi jcns

      His major relevant book is

      http://books.google.co.uk/books?hl=en&lr=&id=RRniFBI8Gi4C&oi=fnd&pg=PR5&dq=lakatos&ots=2lCCc8OOFr&sig=hwg5evND474xplSiBKykva-b-CQ#v=onepage&q=lakatos&f=false">The methodology of scientific research programmes](https://

      http://books.google.co.uk/books?hl=en&lr=&id=RRniFBI8Gi4C&oi=fnd&pg=PR5&dq=lakatos&ots=2lCCc8OOFr&sig=hwg5evND474xplSiBKykva-b-CQ#v=onepage&q=lakatos&f=false) but the wikipedia article

      http://en.wikipedia.org/wiki/Imre_Lakatos"> here ](https://

      http://en.wikipedia.org/wiki/Imre_Lakatos)

      is a good start.

      The key point is that he recognises a scientific theory as having a hard core, the central hypotheses of the theory, surrounded by a belt of auxiliary hypotheses that mediate between the core and actual data. These have to do with the experimental apparatus, sources of noise, subsidiary variables, etc. When the data don't agree with the theory, you alter the auxiliary hypotheses, not the hard core. For example in cosmology, you change your theory of galaxy evolution rather than your cosmological model. Apart from emotional issues and psychological investment in theories, it is this auxiliary structure that makes it so hard to persuade people their theory is wrong: you can always tweek some auxiliary parameter to fit the data (add another epicycle for example). The theory eventually becomes so baroque that it is no longer a satisfactory explanation. But different people differ as to when that occurs:that's when mature judgement comes in.

      Yes Smolin has a book on time in the works (broadly supporting my view).

      best, George

      Hi James

      I think there are two things at work. Firstly physicists recognise that all matter is controlled at the bottom level by the forces between particles; hence physics underlies all (e.g.Dirac stated this in relation to how physics underlies chemistry). There seems to be no room for any other kind of causation. I respond to that claim in the later part of my essay: essentially the context determines how the fundamental interactions work out; they offer opportunities and constraints but do not by themselves determine the outcome.

      Secondly, this bottom-up view is then taken as an underlying principle of faith by hard core reductionists, who simply ignore the contextual effects that in fact occur: for example claiming that biology is controlled bottom up by genes alone, thereby ignoring all the discoveries of epigenetics, which prove this false. But such reductionism is always a cheat, because it is always only partial. Example: Francis Crick famously wrote "You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules". But nerve cells and molecules are made of electrons plus protons and neutrons, which are themselves made of quarks .. so why not "You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of quarks and electrons"? And these themselves are possibly vibrations of superstrings. Why does he stop where he does? - because that's the causal level he understands best! -- he's not a particle physicist. If he assumes that the level of cells and molecules is real, it's an arbitrary assumption unless *all* levels are real - which is my position. It's the only one that makes sense.

      So in the end it's an ideological faith of hardcore reductionists: it's philosophically and/or emotionally driven. That's a further point: scientists like to claim what they do is purely rational. Any impartial study of academia will show this is not the case: emotions and associated rivalries drive a large part of what happens, even as regards physicists. The outcome in terms of mature scientific theories is of course free of these emotions, it is indeed impartial and strictly testable. But they do not arise out of an emotion free environment.

      George

      "If he (Crick) assumes that the level of cells and molecules is real, it's an arbitrary assumption unless *all* levels are real - which is my position. It's the only one that makes sense."

      George, that is a beautifully compact statement of complex system self organization. If consciousness were not non-zero, what could we possibly mean by the term "life?"

      Tom

      Hi George,

      Thank you for the recommendation. Sounds like an interesting approach. I've already ordered a copy (how did we survive before the internet?), and will position it near the top of my "to read" pile.

      Thank you also for the "sneak preview" of Smolin's upcoming book. If it broadly supports your view, I suspect it may also broadly support my view. I like Deutsch's comment: "The way we converge with each other is to converge upon the truth." (The Beginning of Infinity, p. 257.)

      Cheers,

      jcns

      George: ``The present: The ever-changing surface S(τ) separating the future and past - the 'present' - at the time τ is the surface {τ = constant} determined by the integral (20) along a family of fundamental world lines starting at the beginning of space time... But is this well defined, given that there are no preferred world-lines in the flat spacetime of special relativity?... [argument wrt GRT]... therefore there are preferred timelike lines everywhere in any realistic spacetime model... The special relativity argument does not apply.''

      Tom: ``... I think this is consistent with your evolving block universe of spacetime evolution with no preferred surfaces.''

      Dear George:

      I'm just trying to understand your position. In your conception of an evolving block universe, don't you think there are preferred surfaces S(τ) as well as preferred timelike lines? Are you then arguing that these are well-defined in a realistic spacetime model, as opposed to special relativity, because of the existence of matter? Are you perhaps thinking of this in terms of top-down causation, whereby the matter that there is, which exists *in time*, is actually the cause of the ever-changing preferred surface S(τ)? i.e., that the matter that exists is also the cause of *existence*, so described?

      Daryl

      Dear George Ellis,

      You are being asked some very good questions. I hope you're enjoying the process as much as I am. I wish to thank you for pointing out above that one must "get the same arrow of time everywhere", making me realize that my simple summary did not make this point clear. The scale invariance of my solution [prior to symmetry breaking] is [according to Nottale] equivalent to motion invariance and this effectively means that the 'shape' of the solution does not change with scale *or* the passage of time. I improperly characterized this as 'space and no time'. In actuality there can exist global [cosmic] time but it is not discernible when symmetry is unbroken. After symmetry breaks, the gravito-magnetic circulation leads to vortices -- the first cyclic phenomena -- and essentially introduces "local clocks" to space(time). It is conceivable to me that the left-handed nature of these 'clocks' is related to the one-way flow of time.

      Thanks again for pointing out the need for the arrow 'everywhere'.

      Edwin Eugene Klingman

      Dear Tom:

      A three-dimensional space that evolves as time flows is described relativistically by defining a particular foliation of space-time, as describing the ``associated surfaces of constant time [that] are uniquely geometrically and physically determined in any realistic spacetime model''. The foliation is a set of preferred surfaces---but really each one describes the geometry of the evolving three-dimensional space at a particular value of cosmic time.

      Potentially more important than ``changing'' is the fact that the surface is ``existing'', in a real flowing sense. In this physical system, an ``observer'' can move through this evolving space as time progresses; but then, according to relativity theory, ``space'' at any value of ``time'' won't be the same surface for this ``observer'', but a different spacelike hypersurface of the partially complete evolving block space-time that emerges. This is the case even when there are no forces acting on the ``observer''. Relativity then begs the question why the one foliation should be ``preferred'' over any other.

      I think this is the general idea that George has in mind. That was my first question. But then I was curious whether George also thinks this question is answered by associating the bundle of fundamental worldlines with matter, and then saying that these fundamental particles of matter actually *cause* the flow of time, so-defined, and whether this could be thought of as a form of top-down causation.

      Best,

      Daryl