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Radical new take on *uni*verse questions by Smolin, could be important

  1. Apr 4, 2013 #1

    marcus

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    Smolin has a new book (Time Reborn) coming out this month. Amazon has a page on it, with advance reviews.

    He gave a talk on the main ideas at Perimeter in February. I was impressed by the depth and cogency. It is a 60 minute talk followed by a lengthy discussion with Rob Myers, Laurent Freidel, Neil Turok and other members of the Perimeter audience. Here's the video:
    http://pirsa.org/13020146/

    The first 35 minutes lays out the main ideas for wide audience and is readily understandable. I think it would well repay anyone's time to listen to it. He presents certain principles (buttressed by quotes from Dirac, Feynman, Wheeler, Peirce) some going back to Leibniz. In the next 25 minutes he presents new work on a spacetime and quantum dynamics based on those principles which he and a collaborator are currently attempting to simulate in toy version on computer. Some advanced background is needed to understand the final 25 minutes of the talk. He constructs one or more actions/Lagrangians based on simplified models under study.

    The enterprise is high risk. As I recall, the most active audience member is Rob Myers, who keeps commenting and asking questions both during the first hour and in the following 20 minute discussion. But Laurent Freidel is pretty active too. The enterprise could clearly fail. However I find it very interesting and having a real potential to change the foundations.

    I'd appreciate comment from anyone who has listened to (at least the first half hour or so of) the talk.
     
    Last edited: Apr 4, 2013
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  3. Apr 4, 2013 #2

    marcus

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    There was a 2011 pirsa video talk by Smolin that could be viewed as a kind of preamble to this talk:
    http://pirsa.org/11100113/

    One nice thing about the pirsa format is you can click on the slides PDF and get stills as a convenient way of reviewing the talk. I will keep the PDF for the February 2013 talk on my desktop for a while, to have as reference.
    http://pirsa.org/13020146/

    ===example, slide 6 of PDF, quote===
    We start with Leibniz:
    Priciple of sufficient reason (PSR): Every question of the form why does the universe have property X rather than Y must have a rational answer.

    Principle of the identity of the indiscernible (PII): Any two events with the same properties are identical.

    Consequences:
    No unreciprocated actions: No non-dynamical background structures. No unalterable, timeless laws somehow acting inside of time.

    Causal completeness: Explain the universe only in terms of itself. No reference to other universes, non-realized ensembles, or other, Platonic, realms.
    ==endquote==
     
    Last edited: Apr 4, 2013
  4. Apr 4, 2013 #3

    marcus

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    I think those 4 principles in post #2 are worth thinking about so I'll put them by themselves.
    No multiverse.
    At least some laws of nature would seem to be emerging and evolving from a temporal process.
    This is a radically distinct viewpoint, although he cites antecedents for it.
    Laws not standing fixed and eternal outside or above nature, but being an evolving part of nature.
    At first sight it seems so radically different that it would HAVE to be wrong!
    But maybe it isn't.

    Then in the next few slides he lays out some QUESTIONS to be addressed:

    ==sample excerpts taken from slides 7 and 8==
    ....
    ....
    Here are two big questions that we lack sufficient reason for:

    Why these laws?

    Why these initial conditions?


    Both appear to have been finely tuned.

    ....
    ....
    Here are two other issues we will address:
    Why does the unverse have a strong arrow of time?

    What causes events?
    ==endquote==
     
  5. Apr 5, 2013 #4

    Chalnoth

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    I would say that the statements about time and timesless laws don't make sense in the context of this work by Albrecht and Iglesias:
    http://arxiv.org/abs/1003.2566

    Basically, you can always re-cast whatever laws you might write down in terms of some laws that are time-invariant.
     
  6. Apr 5, 2013 #5

    marcus

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    How much of Smolin's talk did you watch? I ask because your comment and the paper you cite do not seem to connect at all with what I was saying or with the talk.

    You seem to be using the word "timeless" to describe a law whose statement simply does not involve the time variable.
     
  7. Apr 5, 2013 #6

    Chalnoth

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    I didn't listen to it. I skimmed the PDF. Maybe he's trying to use it in a way completely different from what his slides seem to imply, but it just doesn't make sense to me the way he writes it, though I guess in part that's because I don't at all know what he means by the claim that time is somehow "real".

    In any event, I really do think the most likely description of our universe is one in which there is a single mathematical structure which describes all interactions, and the slides make it seem like that is precisely what he is attempting to argue against.

    I also am incredibly skeptical as to the idea that he lays out that the fundamental laws of physics should be asymmetric in time and coarse-grain to time-symmetric laws with asymmetric initial conditions. That does not strike me as a pursuit that is likely to bear fruit.
     
  8. Apr 5, 2013 #7

    marcus

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    Listening to the first 30 minutes is a really good way, I find, to understand what he's driving at. I'll try to give a secondhand explanation too, but it is no substitute.

    What you say about not "likely to bear fruit" is true about a lot of highly original ideas that people try out. Most do not succeed. I mentioned earlier that this is a "high risk enterprise". Part of why it looks interesting and valuable to pursue. But it has other important merits in its favor as well, I think. This is not just any off-the-wall gambit.:biggrin:

    To paraphrase, to give additional clarification for those who have watched the first 30 minutes or so, I think he's saying that the "block universe" is a fiction. We know that already, just as "continuous trajectory" of a non relativistic particle is a fiction.

    And the idea of unchanging physical laws is a fiction. The idea of block universe being created together with what we think of as the unchanging laws of physics, which are imagined to govern that block universe without themselves suffering alteration by interaction with it, is contrary to the basic (Leibniz) principles he has adopted. He's following out the consequences of a couple of basic assumptions that I quoted earlier.

    So there is some kind of "meta-law" or process (not necessarily representable in equation form) according to which the emergent regularities (which we think of as the laws of physics) evolve. Those regularities are part of the universe and they evolve along with the rest of the universe that they are part of. They only appear to us to be unchanging fixed proportions or formulae.

    This "meta-law" process, vaguely analogous (one could imagine) to the evolution of biological species where the species takes the place of an "event" in the meta-law scheme, defines a kind of TIME. I would picture this as LAYERS of an evolutionary process, you see pictures of that in the slides PDF. This time is not necessarily the coordinate or real-number parameter sort of time you may habitually think of. It could be more like the layers in sedimentary rock, more like geological or bio-evolutionary time. It is the time which is intrinsic to the evolutionary meta-law process itself.

    However later in the talk, after minute 35, he does get into writing Lagrangians and talking about equations of motion (EoM). To do that he has to use a kind of normalization number r, which you could think of as like a cutoff parameter. Each event is required to have r parents and r offspring. A layer of time is complete when each event in it has the expected number of parent and offspring. This seems to be an arbitrary condition to impose, but it gives him traction so that he can move ahead with the computer simulation.

    It means that the Lagrangian treatment of the second half of the talk, and the computer simulations he and collaborator are working on, are exploratory toy model stuff.

    Anyway it's an interesting adventure, and because what we think of as physical laws evolve along with everything else in the universe according to this process of causation, the time intrinsic to this process must be real and fundamental.

    It is not the t ∈ ℝ calculus time pertaining to some imagined eternal law of physics (that sort of time could be subsumed into some static picture as a coordinate) because what we think of as laws of physics are themselves evolving regularities. In response to your comment then, time in Smolin's sense must be real because the process of evolving nature is fundamental and requires time---other stuff are ephemeral patterns of regularity which appear or develop in the process.

    He is trying to explain the existence of what we consider to be the laws of physics, see the slides 6, 7, 8 where among other things he asks "Why these laws?"
     
    Last edited: Apr 5, 2013
  9. Apr 5, 2013 #8

    Chalnoth

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    Maybe I'll take a look when I get home later.

    To me, this particular feature makes it an off-the-wall gambit. He's basically saying that a macro property which isn't at all visible in our currently-known micro laws, but can be understood as a result of particular initial conditions, must actually be a result of even more microscopic laws. It's a strange sort of averaging that causes an effect to disappear only at intermediate scales, but is clearly-visible both at microscopic and global scales.
     
  10. Apr 5, 2013 #9

    marcus

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    Good. Looking forward to your comments.
     
  11. Apr 7, 2013 #10
    Pretty early on in the talk, he said something like "There are no global Killng vector fields on the config/phase space of GR with cosmological boundary conditions". Can anybody clarify what was meant, or provide a reference?
     
  12. Apr 8, 2013 #11
    It may be felt that my thoughts are not worth putting down but watched the first 40 mins, finally someone with thoughts similar to mine regarding time, he's going in the right direction. Be interested to see if he can put things together or loses sight of the basics in complexity of his own making. If he gets it right then string theory RIP.
     
  13. Apr 8, 2013 #12

    Chalnoth

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    It may help to read up on what a Killing vector field is:
    http://en.wikipedia.org/wiki/Killing_vector_field
     
  14. Apr 8, 2013 #13
    I'm happy with Killing vector fields, but the familiar Killing vector fields of GR generate isometries *of spacetime*.

    However, Smolin says "there are no Killing vector fields or conformal Killing vector fields on this configuration space of general relativity".

    I was thinking maybe when he mentioned the "configuration space of GR", that he was refering to something like Wheeler's superspace. It has a metric (the supermetric), and hence it has the concept of Killing vector fields. But I've never heard a statement like that before in this context. It was supposedly a theorem due to Karel Kuchar.

    However, "configuration space" may have been misleading and he may have just meant something like "cosmological metrics don't admit Killing vectors".
     
  15. Apr 8, 2013 #14

    Chalnoth

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    I think it's a statement that you can always generate a killing vector field locally, or in certain special cases where there is a high degree of symmetry, but you can't apply one to all of space-time (at least not in an expanding universe).
     
  16. Apr 8, 2013 #15
    Here is a link for those interested:
    https://www.amazon.com/Time-Reborn-Crisis-Physics-Universe/dp/0547511728/ref=tmm_hrd_title_0

    It's great to see that they have a Kindle version too:
    https://www.amazon.com/Time-Reborn-Physics-Universe-ebook/dp/B00AEGQPFE/ref=tmm_kin_title_0

    I haven't managed yet to watch the video or read reviews, but for now I'd just like to ask if ideas by Smolin are any near to ideas by Barbour?

    Barbour's book from 2001 titled 'The End Of Time', link:
    https://www.amazon.com/The-End-Time...tmm_hrd_title_0?ie=UTF8&qid=1365453762&sr=1-1
     
    Last edited by a moderator: May 6, 2017
  17. Apr 8, 2013 #16
    I havent had a chance to watch the video yet, but it seems that Smolin is saying the opposite to Barbour who argues time is an illusion. Is that correct?
     
  18. Apr 8, 2013 #17
    This is very interesting to me. Does anyone have a list of physical laws and/or constants that may have, or will change from the BB until now, and into the very distant future?
     
  19. Apr 8, 2013 #18

    marcus

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    That seems correct, though someone who knows Barbour's position on time better than I do should probably answer. For Smolin time is real and fundamental. Not an illusion.

    There is a slight chance that the difference is semantic however. I have to go, back later to address this possibility.
    Back now. I don't really know enough to speculate properly but the way it could turn out to more of a semantic difference is that both are talking about change as being fundamental. That is, no "block universe". So there is no "fourth dimension". In that sense Barbour might say that "time" the fourth dimension does not exist. There is the world, and it changes, and Barbour in a purely classical non-quantum way can show you how, by watching dynamical systems change, you can see time being measured out by change.

    Smolin is certainly more ambitious in that he wants physical law to emerge and quantum probabilities, he wants the whole business to arise from very simple primitives: a set of primitive events that keeps on growing as existing events cause the next generation of events.

    But it seems that for him also there is no block, there is no fourth dimension, there is only a world that keeps changing. So change is the real thing for him (just as I think it may be for Barbour) the difference could be, primarily, that Smolin calls this process of change "time" and Barbour does not call it "time". A basically semantic difference not a deep philosophical opposition, IOW. Just a two cents worth of guess.

    The thing to remember though is that whatever their basic fundamental similarities/differences, Smolin is trying for much much more. He is trying to schematize the whole caboodle, explain why the Laws are these Laws and not some other Laws, and how they came to be, from an extremely simple generic kit of primitives. It is wildly ambitious and so, in that sense, not to be compared with Barbourism.
     
    Last edited: Apr 8, 2013
  20. Apr 8, 2013 #19
    I thought that space and time had no properties and no real existence of their own, unlike sub atomic particles of ponderable matter. All the Physics we have is based ultimately on the way all these particles interact with each other. Their fields and energies and relative locations create the illusion of space and time in our minds like an electron beam creates the illusion of a picture on a CRT.

    A specific Time isn't a location that you can ever travel back to in a time machine, it is an exact position, state and energy of a virtually infinite number of particles thoughout the whole cosmos. Hence reordering this condition is the only way to go back in time, which of course is effectively impossible.
     
  21. Apr 9, 2013 #20
    Actually, I think Smolin was referring to symmetries of superspace (or lack thereof!), since this is what Kuchar was talking about in this abstract

     
  22. Apr 9, 2013 #21
    marcus gets creds for finding this entertaining and challenging lecture.
    .
    I've watched Smolin's video numerous times over the last week., taken copious notes, cross-referenced, listed quotations, and wondered.
    .
    If the lecture has a punch line, it's that, "...Spacetime emerges when there are consistent solutions to all the equations...." And further, "...Spacetime inherits its metric from momentum space...." Note, he's not claiming physical spacetime emerges from momentum space, he's saying that given his simple combinatorial algebra represented by causal trees, a mathematical spacetime emerges. [He declares it is a flat spacetime.]
    .
    Why do i call this the punch line? He uses this discovery of emergent spacetime to illustrate how his new "...framework from which to do quantum calculations..." can reveal physical laws. That's the point of the lecture. His framework is a limited success! He stated clearly that the framework is his goal. He spends the first 40ish minutes explaining the need for his framework, then he reveals his model. Playing with the model reveals that what starts out as a sequential momentum space implies a embedded spacetime. Moreover, he connects this emergence of spacetime repeatedly to his previous discussions and study of relative locality. As he says, "...relative locality also assumes energy precedes position..." When one audience member asks where spacetime comes from, Smolin stalls him a little but refers to another discussion of relative locality as a "hint" as to how spacetime evolves from his model. In other words, the emergence of spacetime is a continuing theme for Smolin. This emergence is important not so much for the result, but that his method produces results at all. His framework is a success, and showing how spacetime can emerge from the fundamental ideas of his framework proves the framework succeeds. [Another limited success is that he can distinguish past from present unambiguously with his algebra. Past events have 2 daughter events, present events have 1 or none. But this declaration doesn't act as a punchline, at least not in this talk.]
    .
    He points out that, "...there's a lot of people who... discuss frameworks for fundamental physics... for whom energy and momentum play no role...." He explains his contemporaries' predilections by referring to their dependency on Noether's theorem which provides that any differentiable symmetry corresponds to a conservation law. Smolin thinks this is too easy, and dubious logic to boot. He argues that eternal laws don't cause things, physical things cause things. He would rather start with something physical such as momentum which generates events according to rules he calls constraints, and describes with Lagrangians. With an algebra describing such a universe, he seeks to discover any laws. This is an intrinsically empirical approach compared to prevailing cosmology, even though the experiments are purely thought experiments. And it's different, very different from prevailing cosmological treatments. It's a kind of chicken or the egg dispute. Do we describe the universe using immutable symmetry and conservation laws? Or do we start with physical events and figure out what possibly mutable ideas are to be discovered? These are colossally different approaches.
    .
    Besides the content, the structure of his lecture also tells me that the emergence of spacetime is the punchline. He spends 40 minutes priming his audience to understand the need for his framework, then he reveals his model over a 5 minute period finishing by declaring that spacetime emerges. At that point he opened up to questions (he was open to questions through out the talk but the frequency of questions increased.) He spends much of the last 40 minutes spelling out details and reassuring the onlookers that he is not proposing a new cosmology, but just a new set of models showing how his method can uncover new truth. Rather than assuming eternal laws a priori, he seeks to discover laws in this case by first describing momenta as edges and events as vertices in a simple 1+1 dimensional model.
    .
    His polemics are multitudinous, and tons of fun. I could take off on several subjects he touches on, but for now I would like to ask fellow posters if anyone has any insight as to how one determines that such a space is "flat." Yes, i see it as a mathematical space, and it seems flattish i suppose, but does anyone understand the topological analysis that would reveal a flat curvature?
    .
    Just to be forthright, i must admit that i personally favor any theory that begins with energy in time and derives space as a result. Thus my apprehension of the emergence of spacetime being the punchline may be colored by my own prejudices. So if other readers find that his comments on emergence of spacetime are merely conclusory to the body of the lecture, i'm fine with that. But the word "punchline" has more zing, and I think he meant to come up with something zingy.
    .
    Regardless, i appreciate any comments.
    -0
     
    Last edited: Apr 9, 2013
  23. Apr 9, 2013 #22
    Smolin does mention the emergence of massless particle dynamics circa minute 49.
    .
    He takes the case where the sequence of events is characterized by a long chain of momenta going preferentially to one daughter at the expense of the other, sequentially. This is like the path of a free particle. When the sum of the "orphaned" daughters' events' momentum is small, and t is small, his equations reduce to standard form for a free relativistic massless particle. {i use the word "orphan," referring to the event which
    gets negligible momentum.}
    .
    Okay, i admit. This too is punchline material.
    -0
     
    Last edited: Apr 9, 2013
  24. Apr 9, 2013 #23

    marcus

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    You've probably dug into it deeper than I. There's not much I can add to what you say here. With a creative paper like this there can be several different interpretations of what the punchline is. Probably there is not just one correct reading of its significance. An original paper can spawn several different lines of thinking and research. So I won't quarrel with your "emergence of space" punchline. It would be pointless to argue which interpretations are better than which others. But I'll tell you how I see it.

    For me, the only reason to be interested in the emergence of space is as a set-up for the emergence of laws of motion and other laws (regularities) of nature that require a geometric framework simply to state them.
    For me, space (i.e. geometry) is just a bunch of geometric relationships like near far inside outside between angles adding up and volume or area related to radius and plus the way these relationships are always changing. The angles change what they add up to, the relation of volume to radius changes, distances change etc.

    It would be incredible if Smolin (and or others) could get dynamic evolving geometry to emerge from a simple basis like a set of primitive "events" and a breeding rule or "causation" principle according to which parent events cause offspring events. It is such a tall order. It almost has to fail. But how great if it succeeds to some degree! Maybe simply to generate a flat geometry, as you said, that would be great already!

    But that is not the goal as I see it. Once one had something that looked like a geometric framework the "real" goal would be to explain laws, how can laws of motion have evolved? How can all this regularity that we see have developed?

    Because he is doing something totally new here: he is challenging the Newtonian paradigm in which Laws stand above and outside the universe and just Are what they Are, eternally, and our job is to discover those laws, and the initial conditions that (under the operation of the laws) led to the present state of affairs.

    That is kind of a pre-Darwinian picture where the animal and plant Species are the Species and they are given, eternally fixed just so. And then Darwin and others figured out how species develop and that you could explain why we have the species that we have. Smolin wants to explain why we have the physical laws that we have.

    It is such an ambitious program that you could almost count on it turning out to be a grandiose debacle. But I find the attempt fascinating. Anyway, for me, it is not just about the emergence of "space" (whatever one imagines that to be).

    But I have to acknowledge that you have plenty of reasons to back up your interpretation. Both interpretations could be valid---one of these things it's useless to argue about.

    I'll try to get a quote from one of his slides that relates to the idea that physical law regularities evolved over time.
     
    Last edited: Apr 9, 2013
  25. Apr 10, 2013 #24
    You (meaning marcus): "...dug...deeper than I..."
    Actually i fixated on the one video. That's all. i'm shallower than a sheet of graphene.
    .
    You" "...With a creative paper like this there can be several different interpretations... not just one correct reading... can spawn several different lines of thinking and research...."
    i agree. The emergence of spacetime and massless relativistic particle dynamics, along with a conveniently simple definition of past and present are modestly successful results. But a particular almost idiosyncratic set of assumptions underlie his selection of algebraic models.
    .
    His is truly a unique style of quantum cosmology. You could call it, "Inside Out Cosmology." Instead of starting with rules and plugging in values, the theory is to find the values, the only values that consistently solve the equations in his algebra (since this is a thought experiment), and then induce rules from outcomes, which he calls events.
    .
    The inquiring soul however can sing along with his 40 minute introductory ballad of fundamental soul searching.
    .
    You: "...For me,... the reason to be interested in the emergence of space is as a set-up for the emergence of laws of motion and other laws... "
    My first interest in time was just after Grampa died. i was almost 5. We got 2 tv stations. i could watch the McCarthy hearings or Flash Gordon. Flash went back in time by exceeding the speed limit for light and saved his buddy. i felt a duty to make a pitch for going back in time to save Grampa. My dad got his best friend to explain enough relativity to me that i understood Flash could never pack enough rocket fuel to go back in time. And importantly, we couldn't save Grampa. The interest in time remained. Space comes in various forms. Physical, mathematical, empty space, vacuum, occupied space. Defining space is difficult and what people wind up with are frequently self assuming definitions. For now, i define physical space as anywhere energy can go, and getting there is time. i get two main things out of my definitions. Trivially, where propagation can't happen, there is no space. Significantly, with a math model, describing where particles can go defines the space of the particular algebra. My question generally is whether the same applies for physical space? It is the presence of physical particles which generates the potential to be elsewhere, not some rule about space? In this sense, physical particles would create space in much the same way that algebraic rules create mathematical space. And that is what we want out of physics after all; to come up with rules that mimic reality. But that's just me.
    .
    You: "...It would be incredible if Smolin (and or others) could get dynamic evolving geometry to emerge..."
    Interesting you should mention this. i got the strong feeling that he was trying not to hotdog. He was definitely soft pitching the overall significance. But i noticed a young woman in the audience [perhaps a co-author?], seemed more gung ho on the idea that they have a discernible cosmology. In the lingo between researchers, that, "they are on to something!" It was hard to pick up on the personal interplay there, but he did mention something about her enthusiasm. She's the one who launched into an explanation to another audience member for why no two things could have exactly the same traits, but it's hard to hear her with my set-up.
    .
    The Principle of Precedence looms large. You could say it is the single most different thing about his cosmology. With it, by analogy, he would take a basketball, a hoop, and some guys, and bounce the ball around, and shoot some baskets, play team keep-away for a while, and then try to write good rules. This, is instead of buying a book, building a court to suit, manufacturing a ball to suit, and starting a league with rules in hand.
    .
    He says he wants cosmology where there's an objective difference between past present and future but i'm stumped as to where he explains the nature of the future. i personally have never seen any example of the future that wasn't just talk about the future, predictions, probability amplitudes. My simple headed interpretation as a result is that the future is at most a subset of the present, consisting of predictions about it. Otherwise, the future DOES NOT exist. He clearly rejects Platonism, thus i would assume he rejects the notion that the future exists too. But not so, i fear. The fact is he plainly said there is an objective difference between future and present. Dang if i can find it in his lecture, though.
    .
    i don't see Darwin here, at all. Darwinian logic is a little circular. The animal survives to replicate because it's fit. It's fit because it survived. It doesn't explain anything, or predict anything. In that sense Darwinian evolutionary theory is not even a scientific theory at all, because you can't make any predictions from it. At least no one has yet. It's little more than a comfortable way to review history. Regarding Darwin i quote Mata Hari on Lancelot Link, "They got pies too, Lance!"
    .
    You: "...It is such an ambitious program that you could almost count on it turning out to be a grandiose debacle..." Yeah, like i said, i get the feeling he doesn't want to hotdog it, for just that reason. And of course, as you say his approach is not just about the emergence of space. Emergence of space, particle, and past/present, are just pretty feathers in his bonnet. He's trying not to do an overt victory dance in the endzone punctuated by spiking the ball, He still has to get further funding. Decorum. Competitors are jealous.
    .
    Back on the flat space question: his algebra looks fractal for short sequences. That would imply less than 2 dimensions. It wouldn't be linear, and i guess you could always map it onto a plane, so being 1.67 dimensions or so wouldn't mean it's NOT flat. How smooth does it have to be to be flat? i assume he's working with the flat topology because it's simpler for now. But you know he's keeping it in mind that experimentation shows space is flat, but he needs a hedge, just in case. U is the hedge. Flat is U=1. He said something about having problems finding any solutions where U is not=1. This could be a fatal flaw, at least for the 2D version. i assume he expects that his findings can be extended to more dimensions. He says the momentum space embeds it's flat algebra in the resultant space, but the momentum space looks more like a fiber to me. Yet being able to put fibers into a plane would seem like a good test for flatness. As an undergrad student i learned that it's really flat because a PhD says so. At any rate, the more i look at flatness the more i feel like a cartoon character myself.
    -0
     
    Last edited: Apr 10, 2013
  26. Apr 10, 2013 #25
    i think i clarified one issue:
    Smolin says, "...Time is real means: all that is real is real in a present moment which is one
    in a succession of moments (12:10)..." This would mean that to the extent that the future is real, it can only be real in a present moment. Yes!!!.. But he goes on to say that rules, and laws can legitimately refer to past, present, and future, for reasons which remain unclear to me. My 8-ball grows dark. Did you already comment on that marcus?
    -0
     
    Last edited: Apr 10, 2013
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