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

[marcus]

Thanks for spotting that Edge monologue by Smolin. It's wide-ranging and enlightening, I think.

 

[negativzero]

This is Smolin at SETI June 24.
http://www.youtube.com/watch?v=-QIJtICy-vE&feature=c4-overview-vl&list=PL7B4FE6C62DCB34E1
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i just watched it and, as usual took notes.
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i don't know everything about him, only that i get him; I've thought a lot of the same things.
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He's a devout relativist.
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Basically, his theory is that when black holes form they create daughter universes in which the rules are only slightly changed from this. In General Relativity mass/energy is not conserved, thus the mass of the resultant daughter universes are either randomized somehow or the parameters are unknown [i'm guessing here]. Further, since this is an ongoing process of universal birthing, universes which produced the most black holes would have the most antecedents and those antecedents [importantly including us] would therefore evolve to be fecund and to have many black holes. He says there are a billion billion in the known universe. i assume he means "currently."
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He reasons that if this theory is true it must be testable. He deduced that neutron stars, if he is correct, must have a physical limit of two solar masses. He claims that this prediction is looking good. Further, he says that if you try to slightly tweak any of the 30 physical parameters in the standard model that at least 12 of the parameters are tuned to maximize the number of black holes in the universe.
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Needless to say, if he is correct, his would a remarkable result. But note, he rejects parallel universes. In fact, in answer to a question, he remarks that Gödel's proof only relates to maths which admit infinite sets. i think he's an advocate for a finite universe, as am i.
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He mentions the "cosmological fallacy": The mistake is to think an experiment in the lab can translate to the entire universe. My example of this is that entropy is only defined in a closed system, yet cosmologists love to toss the term around anyway re the entire universe.
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He clarifies that he's not Darwinian and his theory of evolution is only that our universe is likely the result of maximization of black hole production..."...locally extremizing the number of black holes..."
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Space and gravity are emergent, and time is not. This is the big one where we agree. It's how i found out about him...trying to find somebody who agreed. i think he takes the energy as elemental and dependent upon initial conditions, but frankly, I'm still not sure where he is on energy. i'd like to hear him say energy over time creates space and gravity, but i have yet to hear that one.
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Yep, that's Smolin alright.
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[negativzero]

Smolin doesn't explain what happens when the black holes evaporate, or new stuff falls in. Not in this lecture anyway. By George i think we have a new plot for the Simpsons!
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[marcus]

...He reasons that if this theory is true it must be testable. He deduced that neutron stars, if he is correct, must have a physical limit of two solar masses. He claims that this prediction is looking good...
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Thanks for the video talk link and for sharing your notes. I watched the hour talk. I would recommend others to start at around minute 30:00 and watch the second half hour.
There's also an excellent Pirsa talk from February 2013 that covers the main ideas, actually more completely in several cases.

 

[negativzero]

Marcus i love you and you know that. Ever since you got the restraining order because i wuz sleeepin on yer roof.
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But no.
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2. Two. Dos masas solaris, Amigo.
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[marcus]

Ooops, I already edited from 3 to 2 before I saw your post. Yeah, two solar masses, it comes right around minute 60 in the talk---1:00:00

The link to the February 2013 talk is one I gave in post#1 and I still think it's the best:
http://pirsa.org/13020146/

It must have been somebody else's roof.

 

[negativzero]

But reading over my post i realize that i didn't EMpHasiZe the fact that he contends that he and we all experience the moment. Crucially, he finds no moment of experience in math or physics, nor does he find the human experience of a sequence of moments in physics. Thus math and physics fail. He is not a religious zealot but he believes in his own experience of the moment. He thinks about a lot of stuff but he believes the moment. He seeks a physics which depicts reality itself as a series of moments.
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He and i may diverge somewhat here since i think EVERYthing is in the present. The present is just the sum of the past as the consequences of stuff that has happened is simply brought forward to now. And the future is merely a subset of the present which we designate "predictions." I'm pretty sure he wants to be able to distinguish the past from the present. My point is that this could be a difficult thing to do considering that we are stuck in the present. Unless we can examine the past from the present we can't get anywhere. Everything we know about the past is in the present. The only way we can confirm that there was a past is to check with current circumstances. This is science after all. But i am perfectly willing to point out evidence of the past in the moment.
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i can always wish that deep down in his heart, my new fav cosmetologist thinks everything exists in the present just like li'l me.
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[negativzero]

i notice I'm not the only one to appreciate your efforts Marcus.
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[negativzero]

To Hernik:
You wrote, among other things: "I have a question about the OP Perimeter lecture of Smolin http://pirsa.org/13020146/ from approx 44.00: Here Smolin concludes that Spacetime emerges from the equations.

This part is strange to me. Maybe just because I can't read the equations. :-) But also because It seems to me that space logically was there from the start when the concept of an event is introduced. I fail to understand how an event can take place if not in a space of some kind..."
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i too was struck by Smolin's claim that he sees space-time emerging from the his Knopf algebra. Perhaps all i can do is commiserate with you, but i do have a take on your question.
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Of course he is not declaring that he discovered a physical space, he's talking about finding mathematical descriptions of space in the math.
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Briefly, any sequentiality can been seen as space-like in one dimension. Any series of two pronged forks in the world path of a particle can be seen as 2-dimensional, to the extent that the decision trees for the particles described can be viewed as covering or at least spreading across a plane. To me, this two-dimensionality looks fractal in detail but since fractals can have fractional dimensionality i suppose you could correctly say that his simple tree diagrams approach 2 dimensionality.
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So, given the simple rules for his decision tree diagrams, he begins with a 1-D space-like sequence of events and then connects daughter events such that, as generations are produced, the history of the process takes on a 2-D structure. 2 dimensions is space. If i remember correctly, he said there were some problems extending this notion to 3-D, but since the advent of the holographic principle, he may not consider this to be a fatal flaw. After all, if 3-D is the illusion, 2 dimensions should be enough.
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You also voice concern regarding what you see as an a priori assumption of space for the momentum to inhabit. Have you considered that space is an unneeded construct? What science can measure is fields, more accurately it measures fields on fields. When a physicist predicts all the places a particle might go by tunneling or otherwise, he is describing predictions given fields. "Space" may be a superfluous concept. So for the purposes of these few paragraphs i define space as the places defined by fields where energy can go.
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Smolin's biggest contribution to cosmology may be his theory that from the inside, black holes are new universes similar to ours but possessing a mass not necessarily equal to the imploding mass of the hole as seen from outside the black hole. Mass/energy is not conserved in General Relativity. Lagranges constrain the mass energy, but once the energy goes past the event horizon, the constraints are lost or at least mooshed around. The geometry of the black hole is cut off from the rest of the universe in a non-trivial way. Thus the new universe can have more mass than the stuff that fell in.
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Presumably these new universes expand. Stuff collapsing into the hole initiates the expansion of space perceived from within the hole. So which came first? The stuff, or the space?
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My read, and this is personal, is that the potential for energy to move IS space. Space emerges from the movement of mass/energy. Space is any place a thing could go. But particles determine where they can go according to the rules of fields in their environment. Since gravity, and anti-gravity in the form of dark matter are features of space, i would say that energy over time creates space, gravity, and dark energy.
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Whether the celebritous Dr. Smolin agrees completely with me, i don't know. But we are surely of the same ilk.
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What i think that Smolin hasn't voiced, is that the expansion of space is due to the presence of mass/energy over time. Over time, there are more and more possible places where a particle can be. That IS the expansion of space.
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Your fellow enthusiast,
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[Tanelorn]

negativzero, me2. A couple of years back I rebelled against the notion that the past and future exist and can be traveled to (HG Wells etc). I now believe that only the instant of the present exists. I don't know how big or long the present is though, could it be described as a singularity?

 

[Chalnoth]

negativzero, me2. A couple of years back I rebelled against the notion that the past and future exist and can be traveled to (HG Wells etc). I now believe that only the instant of the present exists. I don't know how big or long the present is though, could it be described as a singularity?

The statement, "only the present exists," doesn't make sense in the light of what we know about relativity.

The issue is that there is no unique definition of "present": different observers will necessarily see different time slicings of the universe as present.

 

[negativzero]

Thanks for your response Chalnoth!
i would put it differently. i'd rather say that GR doesn't distinguish between past, present, and future, but Smolin wants to.
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From the point of view of the pointlike observer, with an instinctive and semantic need to tell the difference, it's difficult to drop references to the past or future. But since this is really about Smolin, it's quite clear that he is adding something to GR. He is adding the human experience of the moment, and a sequence of moments, which add up to a lifetime. Smolin is not delimited by GR in this matter.
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Moreover, he's a guy who is looking for the theory of everything physical. Whether the reader believes such a theory could exist or not, Smolin is seeking what is likely an equation which can be considered as a sum. i put it this way. From my pointlike view, the present is the sum of the past, and the future is a small bit of side logic in the present, which side logic predicts sometimes better sometimes worse. i.e. everything is present. And GR doesn't contradict me either.
Your pointlike compadre,
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[Tanelorn]

Chalnoth, I agree with you, and would modify what I said to say that only the present exists and it a unique present for each frame of reference.

I don't know if this helps, but I have often pondered how would one create make or build a physical Universe? What are you going to make it of, and where are you going to keep it? It is quite mind boggling to me and probably doesn't help much.. but I think Smolin is attempting to provide possible answers, not that we can probably ever know if they are correct, but I personally am most interested in these kind of models which offer these kinds of possible answers. The mathematical modeling approaches are unfortunately well beyond me and I suspect that they cannot ultimately answer these types of questions.

 

[negativzero]

Tanelorn,
"...could [the present: edit] be described as a singularity?"
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If i knew what a physical singularity was for absolute sure, i might be able to answer that. But i can't really get a grip on the mathematical variety of singularness. Oh woe!
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Since the experience of the moment is a feature of human perception, the present occupies an interval, at least in the mind of man. In physics, peeps usually want some kind of instantaneous present...a point in time, some would say.
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i think both Teller, and Feynman agree that what distinguishes the past from the present is collapse. When the wave form collapses the event is securely in the past. Yet even the collapse seems to occur over an interval of some kind.
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Smolin suggested a model of the past and present using Knopf algebra where the past had at least two daughter events and the present had none or only one. i found this to be quite tidy and convenient mathematically but he didn't really present a definition for future, even though he professed a desire to construct a math where past present and future have meaning and where time exists.
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Anyway, i seriously don't know the answers, but i like your questions Tanelorn.
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[Tanelorn]

Thanks negativzero, I like both your questions and answers! I am only any good at questions, I get banned and booed here if I try to talk about answers! In fact I have several times thought of suggesting a sister site to this one, which does not have issues with open discussion. What do you say?

 

[negativzero]

Free expression is a wonderful thing. Some of the folks here are pretty bright though, and they are trained at, steeped in, brainwashed with, physics. Cool!
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i come to check out whether I'm making any sense at all. Luckily marcus had this thread going on Smolin and his quantum loop crowd and i finally found a significant physicist who not only agreed in private, but was willing to stake his reputation on some pretty far out stuff. The guy has balls. The voice of Woody Allen, and the balls of Stephen Colbert.
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i had a similar experience to you. i suggested that a good literary metaphor for time is the abacus. Some say time is a river, or a road, or cyclic, or a snake eating it's tail, or a dime a dance romance, but the abacus brings forward all the calculations one makes in a present physical form. Like the universe.
...Summarily deleted and warned..."NOT PHYSICS!"
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i know. It's a metaphor. You can say the Newtonian universe is clocklike, or is like a computer, or that the universe is it's own mathematics, but apparently the abacus is too old fashioned for the avant garde physics of this era. [insert image of yelling baby here.]
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Cool! I'm an evil man with an evil plan to construct metaphors, and loose them on an unsuspecting world! HA! [insert evil grimace here.]
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[Tanelorn]

negativz, I like the way you think and talk and you have such a lot of energy the kind of which I unfortunately don't have too much left of these days at age 51 or is it 52.. :(

Again I do like all these ideas very much, but just like mathematics, poetry and metaphors probably also will only get us so far, so be prepared for a level of disappointment. We do not know first cause and probably will never be certain of it. So I suspect all that we can ultimately do is write down every possibility that we can possibly think up and hope that we have them all covered. So let's get brainstorming and writing them all down and use SETI to find an 8B year old civilization to compare notes :)

 

[negativzero]

Yes! The million monkeys at a million keyboards answer! Brute word crunching. {The tax codes were written this way.}
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It was expensive. All the monkey chow, all the waste.
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And then someone pointed out that even though my capuchins could type with hands AND feet, that there were about 50 keys and the shift button. So for any lengthy work such as, "the whole theory of everything in 50 words or less [not counting the title]," you are actually talking about 300 or so keystrokes. There are about 100^300 permutations the monkeys could come up with, which permutations would specifically NOT be the whole theory of everything, for any 300 keystrokes.
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A google is only 10^100.
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Obviously, i needed more monkeys.
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The above is a parable. Parables are literary. But Smolin, i think, has found himself in a similar situation with string theory. Millions and millions of theories are available, but which ones represent reality? Critics say string theory is untestable so far. So no one can pick a theory.
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Similarly he is disenchanted with loop quantum gravity. i think he made it clear here:
http://www.edge.org/conversation/think-about-nature
this link was also given in the thread above.
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You were saying that we will never know first cause, but isn't it amazing that so many things are agreed upon right now in cosmology? That there is expansion. Something like a start. That the atomic theory is important to understanding the universe, and the universe itself has a quantum nature. But agreeing on stuff is not knowing it. Smolin believes in the moment.
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Me too.
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Now try and figure out what a moment is.
In tennis, the moment is what i should have done 1/10th second ago.
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[Chalnoth]

Chalnoth, I agree with you, and would modify what I said to say that only the present exists and it a unique present for each frame of reference.

That doesn't make any sense. How can existence be an observer-dependent property?

Anyway, in General Relativity, the result is completely unambiguous: the past, present, and future are all described by a single four-dimensional manifold. The future has as much real existence as the past or present. So yes, if it were possible to construct a traversable space-time path that led back to the past, you could certainly traverse that path to get there.

 

[Tanelorn]

Chalnoth, are you not using mathematics to prove one possible view of reality, but that view might yet still not be the truth of our reality? Sure we can write down a coordinate as consisting of three spatial numbers and a temporal one and then we can think that this unique 4D point really does exist forever and that with the right technology we can travel there. In our minds it does, and I used to believe it that way myself (HG Wells etc), but I am now no longer so sure that it accurately represents reality. I now believe that we would literally need to somehow create another Universe exactly like ours and let it exist until that moment in time has been reached again in order to experience that unique moment of time and existence again. Past, present or future moments, once the moment has happened it is over and gone.

I agree that every moment in the past did exist for a fleetingly short time, but now these moments are gone, and the past ceases to exist as soon as time has marched on to the next moment. So I am suggesting that we exist in a completely transitory universe, in effect here today and gone tomorrow. It is my view of the nature of time and reality that has changed, I no longer see a moment in time as being like the three dimensions and coordinates of space and somewhere that we can travel to. All that ever remains of any moment in the past is the information, which determines through cause and effect of particle interactions the next instantaneous moment of the present. The present being no larger than: http://en.wikipedia.org/wiki/Planck_time.

To sum up, moments in time are not being stored in perpetuity and reality exists only in the movement of time as it creates each new present.
I found this amusing, relevant and predictable when I read about it because either we go extinct or no one in the next 10^100 years is able to travel to a past moment in time:
http://www.dailymail.co.uk/sciencet...king-held-party-time-travellers--turned-.htmlnegativz we cannot ever know first cause because every time we think we have found it we then need to ask ok but what caused that first cause? The greatest tragedy of our existence is not that we are mortal but that we almost certainly pass without ever knowing what something approaching first cause is, and what it really was all about.

 

[Chalnoth]

Chalnoth, are you not using mathematics to prove one possible view of reality, but that view might yet still not be the truth of our reality?

I don't think there's any question that General Relativity accurately describes the large-scale behavior of our universe. It's just too well-tested for that. There's no question that the theory breaks down at very strong space-time curvature, or that it has to be modified to take into account quantum mechanics. But there's also good reason to be extremely confident that it has the general, large-scale picture correct.

Sure we can write down a coordinate as consisting of three spatial numbers and a temporal one and then we can think that this unique 4D point really does exist forever

I think the problem here is that you're thinking of some sort of "super time" that exists outside of the time we experience. This isn't the case: there's just time. A point in the past doesn't "always" exist. It exists in the past. The past is perhaps best understood as another location, separated from us in a direction we can't actually point.

There may be good reasons why time machines are impossible, but this isn't one of them.

 

[Tanelorn]

I am still trying to find the right words to describe what I meant and the closest metaphor I can find is the way that a computer generates a 3D world in a 3D game. Each moment is calculated on the moment that came immediately before, and when the calculation is complete, the moment and information is lost or discarded. Reality in this model is therefore a succession of moments and the past is gone. Can such a view be disproved?

 

[Chalnoth]

I am still trying to find the right words to describe what I meant and the closest metaphor I can find is the way that a computer generates a 3D world in a 3D game. Each moment is calculatated on the moment the one that came immediately before it and when the calculation is complete the moment and information is lost or discarded. Reality in this model is a succession of moments.

Right. I know what you're trying to say. I don't think it is a workable model, however. The problem is that another viewer might see a different slice in time.

The way I like to understand the way this works instead is that the physical laws provide a system of constraints. If you were to take the entire wavefunction of the universe at one particular time-slicing, you could, had you a powerful enough computer, compute the precise wavefunction of the universe for every other time-slicing. No time-slicing is more or less real than any other, and there isn't a sense in which one time slicing ceases to exist as another comes into existence: that view can't work in light of the fact that different observers see intersecting time slices.

The really interesting bits are in how we can translate from this "bird's eye" view of the universe to our own view.

 

[negativzero]

Sequentiality is a timelike feature of the pointlike perspective. i don't see how that makes it's timeline false or that sequentiality from another point of view is necessarily contradictory. Not that anyone said that, but i hold out hope that there will be a picture of time in physics that includes time as fundamental, and doesn't deny the human perspective.
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Smolin is trying to build a quantum picture of what is going on, and that, to a large extent, is going to be about particles. Particles are pretty pointlike. He begins with conservation of momentum which drives the process to the next event, in a series of events.
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His models require event generators, which are laws which constrain the propagation
of momenta in the creation of new events. So you have a bunch of [particles] interacting, momenta constrained in a series of events, and then he defines past as having a sufficient number of daughter events (at least 2) and the present as having an insufficient number of daughter events (1 or none) to pass the test of a past event.
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Notice he's not just taking the point of view of one event, or one series of conserved momenta. He's looking at the whole crowd of events and picking which constitute past and which constitute present.
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Pretty nifty really. Omniscient?
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[i should say he's not advocating this theory, it's just one of the models he's been thinking about.]

 

[Tanelorn]

Due to the nature of time, our reality can only ever exist in the ever moving Planck time slice of the present and can only be dependent on the particle interactions from the immediately preceding Planck time slice.

None of the other past time slices interact physically on the present time slice any more than those of the future do, and so from our point of view they no longer exist.

 

[Chalnoth]

Due to the nature of time, our reality can only ever exist in the ever moving Planck time slice of the present and can only be dependent on the particle interactions from the immediately preceding Planck time slice.

None of the other past time slices interact physically on the present time slice any more than those of the future do, and so from our point of view they no longer exist.

By that definition, there are no interactions at all.

 

[Tanelorn]

I am saying that only what is going on in the immediately preceding time slice has an effect on the new present time slice.

 

[Chalnoth]

I am saying that only what is going on in the immediately preceding time slice has an effect on the new present time slice.

Well, no. If you have all of the information of the immediately-following slice, you can also compute the full configuration of the current slice. For that matter, if you have any time slice at all, you can (with enough processing power), compute any other slice. So there's no way in which the immediately-preceding slice is unique in this regard.

 

[Tanelorn]

Well, no. If you have all of the information of the immediately-following slice, you can also compute the full configuration of the current slice. For that matter, if you have any time slice at all, you can (with enough processing power), compute any other slice. So there's no way in which the immediately-preceding slice is unique in this regard.

Yes, but the only time slice needed to determine the next time slice is the one immediately before. None of the other time slices are required, or have any effect on the present time slice, and therefore they are no longer real. Only the ever moving present time slice is real.

It all depends on how time outside of the present time slice works and whether time is perpetual or as I describing an ever moving very thin slice of present time. A perpetual model of time would require the storage of at least 10^44 copies of the entire universe per second. Since our movement through time cannot ever be broken anyway, perpetual time seems wasteful and nature does not like waste. So I now question HG Wells model of time.

 

[Chalnoth]

Yes, but the only time slice needed to determine the next time slice is the one immediately before. None of the other time slices are required,

What do you mean by, "required?" Any time slice is sufficient. Doesn't matter which one. You don't need the immediately-preceding one. You can pick any time slice you want.

or have any effect on the present time slice, and therefore they are no longer real. Only the ever moving present time slice is real.

So, according to you, a different observer moving relative to me who sees a different time slicing interprets most of my present time slice as being not real.

How does that make any sense?

Furthermore, this definition of reality includes parts of the universe that always have been and always will be causally disconnected from an observer.

 

[Tanelorn]

Chalnoth, sorry I think I am just repeating myself so perhaps I don't make any sense. If I may, just one last time:

Consider the video game analogy, all that is required to compute iteration n is iteration n-1. It is not necessary to store iteration n-2, or any older iteration data, so in an efficient system any data older than iteration n-1 would be discarded as unnecessary and therefore no longer exist.

General relativity, special relativity, and frames of reference effects not withstanding, I am suggesting that only particle interaction data in time slice n-1 are required to be able to compute or create time slice n, nothing more than this.

From this perspective we would literally have to reverse the direction of time (equivalent to the computer clock, which unfortunately can only be positive!) for the entire universe to be able take the present time slice backwards in time and we have no control over the direction of the arrow of time at least from inside our Universe. The past is therefore gone and the only way of recreating a past iteration would be to start the whole thing over again from time slice or iteration 0.

The Universe in this model resembles a massively parallel computer and perhaps the finite speed of light and other properties of the Universe are due to the equivalent of computer hardware limitations. Or perhaps the finite speed of light is just necessary just to prevent everything in the whole universe interacting simultaneously with everything else. Cause and effect could potentially become completely unstable if the speed of light were not finite.

I saw an episode of wormhole recently where they proposed another "computer" metaphor like this, and they mentioned how particle interactions, or was it diffraction patterns, become more precise depending on how closely they are being observed. i.e. the "computer" appears to calculate particle data more precisely depending on whether or not a more exact measurement is being required.

 

[negativzero]

The time as a film analogy suggests that since a film may be run backward, time could somehow run backward too. A universe where time ran backward like a film would presume that the forward version had already been made, or it couldn't be reversed. That would require a deterministic universe and would throw the uncertainty principle out the window.
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Any picture of time reversal from a piont-like perspective is going to require that you [AND I MEAN YOU SIR!] stop every single particle and reverse it's direction back to precisely the position that it occupied at the time you want to go back to, and then...then...you will have to start everything back up again in the propah directioines senior!
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No one has evah proved that quantum reality is randomized, and they may not ever prove it {because after all, the sense of randomness might just be some cosmological dirty trick}, but i can't prove it is not randomized. Seems to be experimentally confirmed to an extent--Tomas Erber, Boston College. decay of single mercury atom ions. It looks to me like trying to run time back and forth in an attempt to repeat outcomes is futile at the atomic level. Running the film backward will not be exact, then running it forward will not be exact...Heisenberg. We can't suspend all the rules of physics to nurture our wish for time travel...'What's your name?..."Weena!"';
--H.G.Wells.
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Show me the past! If it exists, show it. Same with the future bud. I'm from Missourri on this one.
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Any version of the future that i have ever heard of is right here and now in the present. All there really is of the future, is predictions. And I've been looking too.
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Once the wave form has collapsed, it's history. Von Neumann and Feynman would agree with me. We are talking particles here, not relativity.
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It doesn't matter what perspective one takes, one can't change the outcome. Collapse means, "It's ovah BAby!"
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But that's all me. Smolin i think is taking a more fundamental and less didactic view than myself. Regardless of any GR, he takes the sequential world path seriously. {By the way, the sequential world path is personal. It's yours and mine.} He suggests that one can build a two a dimensional reality from a whole bunch of 1 dimensional sequential life paths, and put together a possible template for a quantum 2-D space evolving or emerging as a result. He even leaves "u" as a possible bump out of 2-D into 3-D, but he says u is not working real well, so far.
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[Tanelorn]

negativzero, thanks, I think what you are saying is similar to what I was saying. I made one mistake though, you cannot recreate the exact same Universe again just by starting over, because it will be a totally unique and random Universe each time, even if all the laws are the same.

The alternative to this instantaneous present time slice model is the one where every piece of data for every particle is stored at 10^44 frames per second for the entire Universe. Then the data can be retrieved and a past reality recreated which then produces an effect similar to time travel, although it is not really an accurate description. Perhaps whoever is in charge is using data compression techniques and recording specific data for further offline analysis!


What could the purpose of such a Universe be? recreational perhaps? I hope I am just joking.."He even leaves "u" as a possible bump out of 2-D into 3-D, but he says u is not working real well, so far."
btw is u me, or the Universe, or something else?

 

[negativzero]

Tanelorn, my friends call me "minus,"

In the well known documentary, Star Trek, when folks get caught in a "time loop," they experience deja vu.
Somehow, the human mind transcends the physical limits of time keeping [note, the crew's wrist watches don't "ping" when time reverses].
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After playing exactly 10^44 do-overs in videogames, i can see why the intrepid crew would want some do-overs themselves. With enough opportunities, perhaps we can finally or perhaps perpetually get THIS UNVERSE right! i'd like to see my neighbors backyard cleaned up, for instance.
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If it's any consolation, judging by the rate of the wind thru my hair, we do seem to be "traveling" thru time but can't quite get out of first gear.
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Unfortunately, the only way to adjust time rate seems to be by changing relative acceleration or gravity wells.
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i'm already running as fast as i can, and I'm not in the market for a new gravity well right now.
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At any rate, since Smolin believes the universe is unique and emerging, i'd bet that he doesn't, "...tolerate do-ovahs 'roun' heah!"
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[negativzero]

Tanelorn: "...Yes, but the only time slice needed to determine the next time slice is the one immediately before. None of the other time slices are required..."
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Back to metaphors between computation and the universe itself, one of my calculus teachers used to tell me, that Alonso Church lectured him, i think it was at UCLA.
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Church would write a line of math, erase it, write the next line, erase that, and so on writing in one chalky spot on the blackboard, eraser in one hand, chalk in the other.
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Smolin wants physics where all particles in the universe have a shared past, with some kind of recordation of it, he called it "memory." Laws evolve as the result of memory of physical events. In some important way, something about the past is not "erased." [That part, i would call, "the present," but it's not about me.] This is not so different really from the oft repeated assertion that the current state of cosmological events is the result purely of initial conditions given the nature of space. The difference is really that the second view is from outside the system and the first view, Smolin's, is by the participant observer, trying to put it together from inside the system. While in one sense he is walking from GR, in the other, stuff is still relative in his inquiry; he keeps some rules of GR.
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The inside-out view allows for an evolutionary assumption. i personally am very reluctant to accept any "other universes" idea, as the experimental data is not there. However he mentioned recently at SETI, if it can be shown that the 30 parameters of the standard model are finely tweaked to maximize black hole production, not HUMAN production, but black holes, then his theory has credibility. And that would strongly imply NOT infinite parallel universes, but a kind of meta-time, which would connect a multitude of universes in a self replicating process, where each universe would be only a little different than it's mother. The meta-time would be the sequentiality of mother and daughter universes.
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