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Smolin is working on a new book

  1. Oct 20, 2009 #1
    Lee smolin is working on a new book named "The Reality of Time".


    "The event is also covered in the blogosphere by Martin Durrani from PhysicsWorld who is presently Inside the Perimeter and intrigued by BlackBerries and Blackboards. Sean Carroll talked about time and Neil Turok lets us know that Lee Smolin is working on a new book called "The Reality of Time." Yes, it's about time."


    http://backreaction.blogspot.com/
     
  2. jcsd
  3. Oct 20, 2009 #2
    Has he finished the prevoius one "The Reality of Space" yet?
     
  4. Oct 20, 2009 #3

    Demystifier

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    When he finishes both books, then he can easily write two new books:
    "The reality of space and time"
    "The reality of spacetime"
    After that, he will be ready for a more ambitious project:
    "The reality of space, time and matter"
    Obviously, after that his next project will be:
    "What is reality?"
    which he will finally answer in his final masterpiece:
    "The reality"
     
  5. Oct 20, 2009 #4

    Fra

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    I don't know if it's the same book he is suppsed to write with R Unger, or if it's another one. I suspect it's the same.

    I'm not sure how popularized it will be but in either case I look forward to it. Not to read the popularized thing again, because I've read enough of smolins ponderings to get the picture. But I'm curious to see if he has developed it to the next level where it may give rise to a new more concrete research program.

    The title reality of time might sound silly but it's most probably not as silly as it sounds.

    The idea behind reality of time, and evolving law is to constrast with the structural realist position of eternal timeless law, which is at least equally silly once you note that the best of human science has in fact evolved, and continues to do so.

    So "reality of time", shouldn't be confused with absolute time, or violation of relativity in the usualy sense, it rather IMHO just another way of putting the idea of evolving law.

    The complete removal of time, like alot of people envision, also removes the physical observational basis that is needed for science, and progress of science. This is why I read smolins "reality of time" as an argument for evolving law, rather than some existence of a observer independent universal global time IN WHICH the laws evolve.

    So reality of time, could simply refer to "the reality of evolving physical law" - in contrast to the eternal law and removal of time like say rovelli and others.

    However this distinction was quite fuzzy in Smolins previous arguments I've seen, either he was not good at conveying the points, or he was truly uncertain on what it is. I hope that he has improved and refined them. So I look forward to this book.

    /Fredrik
     
  6. Oct 20, 2009 #5
    Your suspicion is correct.
     
  7. Oct 20, 2009 #6

    marcus

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    Smolin gave a talk just about one year ago---on 2 October 2008---titled
    On the reality of time and the evolution of laws.
    Here are links to video and to a PDF file of slides:
    http://pirsa.org/08100049/

    At that time I heard an estimate that his book with Unger was at least a year away. That they hopefully could have a finished manuscript by October 2009. Both are busy, who knows how long before the book actually gets to publisher? and then comes months of work at the publisher.

    At that time IIRC the provisional title of the book was "Do the Laws of Nature Evolve?"

    I think Neil Turok may have only mentioned the short title. The full title might be something longer, like for instance
    "The Reality of Time: Do the Laws of Nature Evolve?"
    or something else like that.

    But let's suppose that the title is just what Turok said. I think it's an OK title.

    Here's the abstract of the October 2008 talk:
    ==quote Smolin==
    Abstract: There are a number of arguments in the philosophical, physical and cosmological literatures for the thesis that time is not fundamental to the description of nature. According to this view, time should be only an approximate notion which emerges from a more fundamental, timeless description only in certain limiting approximations. My first task is to review these arguments and explain why they fail. I will then examine the opposite view, which is that time and change are fundamental and, indeed, are perhaps the only aspects of reality that are not emergent from a more fundamental, microscopic description. The argument involves several aspects of contemporary physics and cosmology including 1) the problem of the landscape of string theory, 2) cosmological inflation and the problem of initial conditions, 3) the interpretation of the “wavefunction of the universe,” and the problem of what is an observable in classical and quantum general relativity. It also involves issues in the foundations of mathematics and the issue of the proper understanding of the role of mathematics in physics. The view that time is real and not emergent is, I will argue, supported by considerations arising from all these issues It leads finally to a need for a notion of law in cosmology which replaces the freedom to choose initial conditions with a notion of laws evolving in time. The arguments presented here have been developed in collaboration with Roberto Mangabeira Unger .
    ==endquote==

    I sometimes have encountered the related, but simpler, idea that spacetime is "made of causality". That its essential skeleton is the structure of lightcones that represent the causal ordering of events. That scale is of secondary importance, and only this causal ordering matters. Everything else arises from the bare fact of causality. The term "conformal" crops up in this context.

    They are saying something apparently different---not that causality is fundamental, but that "time and change" could be the only aspects of reality that are not emergent from some more elemental description.

    The reality of time thesis reminds me of a talk called Quantum Knowledge that I heard given by Robin Blume-Kohout in which he described realtime data compression by a quantum agent. He also discussed agents who use qnowledge to make bets about the future.
    http://pirsa.org/09100089/

    To me this seems to capture the essence of what we mean by "Laws of Nature". They are a constantly evolving form of data compression which lets us make bets about the future.
    There is no evidence that an eternal immutable set of laws exists. At least that I can see.
    Maybe the laws themselves evolve, and likewise our knowledge of them evolves.

    And for me this Robin B-K concept of "Laws of Nature" cannot be meaningful unless time is real. It the Laws evolve, then they must evolve in some kind of universal Time. Maybe it is not the same time perceived by thisorthat observer, by me or you, but there must be some fundamental progression.

    Contrast this with the essay by Rovelli which won first community prize in the 2008 FQXi essay contest. It was called "Forget Time". In Rovelli's treatment time appears to emerge from something more fundamental. At a basic level it does not exist. This seems diametrically opposed to what Smolin is saying. There is definitely a tension between the two points of view.
     
    Last edited: Oct 20, 2009
  8. Oct 20, 2009 #7

    Fra

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    This is right on the money in my view. It's exactly how I see it as well, more or less litteraly speaking - but the technical challange is to describe this without relying on old style "information theory", the data compression needs to be described completely relationally from an inside view. I haven't seen anyone yet capturing this vision into a viable evolving mathematical framework.

    But it seems more and more people are coming closer to this vision.

    However, I think there is still some degree of uncertainty as to what "fundamental" actually means. Does fundamental refer to "observer indepdendent", or can there be observer dependent fundamental things in the sense of beeing subjectively irreducible? or does it refer to realist parts that must be taken for granted?

    I also see strong paralells to the gaming view and evolving law, but to me there need not be a observer independent - and therefore realist type - constructs for this to make sense.

    But this is the area where I found Smolins position to be unclear so far. For example, wether evolving law means there has to be a meta law describing it? In the talk he receives that question and answers he doesn't know. I do not think there is or has to be a meta law. However that makes some things simply undecidable, but I think that's a property of natures workings and not a flaw in the abstraction.

    /Fredrik
     
  9. Oct 20, 2009 #8

    RUTA

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    In his book "The Trouble with Physics," he writes, "The problem of quantum mechanics is unlikely to be solved in isolation; instead, the solution will probably emerge as we make progress on the greater effort to unify physics." How will his "evolving laws" idea resolve the foundational questions of QM?
     
  10. Oct 20, 2009 #9

    marcus

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    BTW, the idea that physical laws result from an evolutionary process goes back to Charles Peirce (born 1839) the founder of the (American) Pragmatist school of philosophy. Peirce was primarily known as a scientist--his field was chemistry. But he left writings in the philosophy of science, and in logic whose importance was only recognized later.

    RUTA,
    I don't see how this expected book, of which we can get a foretaste in Smolin's October 2008 video lecture, can resolve "foundational questions of QM".
    I recognize that foundations of QM is an exciting challenging field, and perhaps Smolin and Unger's book will contribute to it in some way, but I think the main thrust is elsewhere.

    I think we have a serious bunch of questions surrounding the idea of physical law itself.
    I think S&U intend their book to clarify the idea of physical law.
    It is a legitimate (and potentially interesting) thing to try to do on its own merits, quite apart from resolving QM foundation issues.

    On the other hand, just because I can't see how the book will bear on QM foundations doesn't mean it won't. Maybe I should watch that October 2008 lecture again and then try to reply to your question.
     
  11. Oct 20, 2009 #10

    RUTA

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    Thanks marcus, I'll ck that video. I saw him speak on his neo-Heraclitean view last Sep and don't remember him saying anything about foundational issues. I expected he would have something to say about "the most serious problem of modern science" (Trouble with Physics) in his next book.
     
  12. Oct 21, 2009 #11

    Fra

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    I like alot of smolins general reasoning and direction, but the edge of what he is doing is still fuzzy, so I can't speak for smolins next steps, but I can speak for myself and how my view of this evolving law roughly will adress QM:

    In short, quantum logic is different from classical logic, similarly one can classify inference systems as implementing quantum logic or not. In certain cases an inference system that implements quantum logic is simply more predictive and thus more fit, thus this is why there are quantum phenomena in nature - it's a result of evolution.

    For me at least (here I think I certainly deviate at least from smolins current reasoning) there is no distinction between classical and quantum or magic "quantization procedures" there is just one general abstraction which I think of as a general "inference system" that comes with a natural action. So one you know the inference system, you know the action. But this inference system is also responding to feedback from the environment, meaning that it evolves.

    In this view, classical inference and quantum inference kind of only special cases. I pretty much view quantum inference as an inference that contains a kind of data compression, that classical logic doesn't. This is similar to the reasning of the "quantum knowledge" thread martin posted https://www.physicsforums.com/showthread.php?t=347164 (though I still haven't had time to view to the talk).

    The basics is simple to understand I think, consider how to process a stream of data, and at the same time use this datastream to predict the next data under the constraint of finite information capacity - you can not keep the entire time history. IF you can do this well, you can EXPLOIT your predictive power to even capture degrees of freedom from the environment, and thus grow your own capacity (this is a remote connection to origin of mass).

    Now obviously one can imagine different strategies here. Either you just keep the most recent "time window", and based you inference on this, or you keep say an evolving probability distribution of events, and base your inference on this, or you can split your capacity and use part of it to store a distribution, and part of if to perhaps store FFT data.

    It's not hard to see thta in the case of periodic phenomena it would be very favourable to store frequency components only.

    This can be developed, and furthermore the action of this inference system will depend on the kind of datacompression it uses. One might even say that difference interactions might be explained by applying different transformations or compressions to the inference systems.

    This is how I envision it, and it fits both into the evolving law idea as well as solving in a good way alot of the foundational QM things. HOwever it will not restore realism, it rather removes MORE of the realism that QM does, since it even removes the realism of physical law.

    Therefore one could even MAYBE characterize say an electron, with a particular "inference system", and this inference system explains the action of an electron. As to WHY the electron has a particular action and not something else, I think is evolutionary, and hopefully we can understand why the electrons action is at a fitness peak, so that disturbing it would simply destabilise it.

    Hopefully this evolving inference/compression system framework will predict a discrete spectrum of stable inference systems - these things should correspond to (in the low complexity limit) to "elementary particles", relative to the inference system from which this inference itself is done - which would probably be the earth based human science level.

    /Fredrik
     
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