The Infinite Cosmic Lattice

Discussions ranging from space technology, near-earth and solar system missions, to efforts to understand the large-scale structure of the cosmos.

Re: The Infinite Cosmic Lattice

Postby Gregorygregg1 on October 15th, 2012, 1:30 am 

Dave_Oblad wrote:I'd lose the "Infinite" part of your lattice concept. Infinity can not exist by it's own definition. As a concept.. fine.. but in the real world.. it's no more than an unachievable goal.

BurtJordaan wrote:True, but I'll stick to the 'infinite flat lattice' (not bend into a grand circle in 4 dimensions) for now. It's a lot simpler to work with. Otherwise, parallel lines will not remain parallel, even if you 'freeze-frame' the expansion and measure. If it's not infinite, let's call it near-infinite, large enough so that we will never find the edge


The thing that is not explained in this, or any other expanding universe theory is "what is the universe expanding into?" It is fine for lattices to get bigger, but to do that, something must be displaced. You refer to "The Edge", I assume you misspoke.
BurtJordaan wrote:
But the whole lattice concept is one of variable density! The average density decreases all the time.

I understood you to imply that dimension changes, but only where there is no substance. You restrict the expansion of your lattice to portions of space with less than subatomic particle density since you do not allow the disruption of the integrity of subatomic particles by expansion. In other words, is the interpretation correct that only the universe without density is expanding; the universe with density does not? Does this imply that expansion would not be uniform because density in the universe is not uniform? Does it also imply there can be change that does not involve substance?
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Re: The Infinite Cosmic Lattice

Postby cirenor on October 15th, 2012, 5:45 am 

To Dave O : The ultimate ruler throughout all this is the speed of light. The speed of light remains constant whatever the size of the blue bars and whatever their rate of expansion. Even though photons are stretched over their duration of travel the speed of their immediate wavefront remains constant. It fixes the metric of distances whether spacelike or spacetimelike. Now the speed of light is intimately tied up with mass, and with the values of any forces binding masses together. So even though spactime might be very gradually expanding underneath any agglomerations of matter, the motions of particles within the various force fields constraining them will be constantly compensating for any stretch going on in the underlying spacetime. As for the particles themselves, my understanding is that for the fundamental ones the concept of size gets very murky anyway. Up at the level of stars and galaxies spacetime expansion will be working to pull them apart, while gravity will be operating to keep them in relative stasis. I'm guessing that at these scales gravity is the very much larger force (is it OK to talk of the expansion as having a force?)

I see two interesting points though:
1) At the local particle level there must be some very tiny energy component in their respective motions to compensate for any drift due to space time expansion.
2) On the large scale, where spacetime expansion effects are of the same order as gravitational effects, there must be some distance for any given pair of masses where the two effects are in balance. So somewhere out at the level of superclusters there must be a point where the binding effect of gravitation is overwhelmed by cosmic expansion and the large scale expansion we see takes over?
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 15th, 2012, 11:15 am 

Gregorygregg1 wrote:The thing that is not explained in this, or any other expanding universe theory is "what is the universe expanding into?" It is fine for lattices to get bigger, but to do that, something must be displaced. You refer to "The Edge", I assume you misspoke.

No my lattice analogy represent an infinite cosmos, but I recognize that we do not have direct evidence for that. If the geometry is perfectly flat and it is not infinite, then there may be an end to it. We simply don't know. Hence, by Occam's razor, it is better to make it infinite. In practice it may be spherical though, finite with no edges.

BurtJordaan wrote:
But the whole lattice concept is one of variable density! The average density decreases all the time.

Gregorygregg1 wrote:I understood you to imply that dimension changes, but only where there is no substance. You restrict the expansion of your lattice to portions of space with less than subatomic particle density since you do not allow the disruption of the integrity of subatomic particles by expansion.

No, it is restricted to areas that are not gravitationally bound, i.e. the rather empty areas between clusters (the blue bars and the empty spaces of the lattice). I do not think it is valid to talk about particle sizes here. It is the integrity of clusters of galaxies that are not disrupted by expansion. There is obviously a huge difference.

In other words, is the interpretation correct that only the universe without density is expanding; the universe with density does not?

You can say this, but note the more correct interpretation in the prior paragraph.

Does this imply that expansion would not be uniform because density in the universe is not uniform? Does it also imply there can be change that does not involve substance?

Yes, expansion is only approximately uniform if averaged over large scales, 100 million lightyears or so. Just like the lattice's expansion that is not uniform between bars and cubes, but all blue bars expand at the same rate - hence overall it is uniform.
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Re: The Infinite Cosmic Lattice

Postby Dave_Oblad on October 15th, 2012, 11:50 pm 

Hi Jorrie,

Ok, so I took your perfectly symmetrical lattice and added some Galactic Clusters (not shown) following your rules that the lattice only stretches between Galactic clusters but not inside them. Given some semi-random placement of Clusters, your lattice becomes distorted as shown below:

GridFlex.jpg
Large scale view of Lattice with clusters

Of course, this will become much worse over time. It's hard to stretch a rubber sheet uniformly when you have inflexible objects glued on it. But you seem to prefer that the mass objects don't expand with the lattice because if they did, then everything would be expanding and thus nothing is expanding, relatively speaking of course.

Now you stated that the rungs of the lattice are relative to the frequency of light. But we know the wavelength of light is an exact measure of Planck lengths. Therefore, to accept the premise of non-uniform expansion because of Galaxy clusters and that the lattice must extend all the way down to Planck lengths in order for your frequency functions to remain calibrated to the lattice rungs, then the speed of light must be variable because the measure of distance has become a variable.

Also, if the wavelength of light leaves a Galaxy Cluster and becomes stretched due to the expansion of space, then when it re-enters another Galaxy Cluster that isn't stretched (same rung lengths as the first one exited) then why doesn't the wavelength revert back to it's original wavelength? In other words, why does the wavelength only change (stretch) leaving a cluster but not (shrink) when entering another?

Something for you to chew on while I call it a night.. It's a night..lol.

Best Regards,
Dave :^)
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Re: The Infinite Cosmic Lattice

Postby JohnD on October 16th, 2012, 1:35 am 

Thank you one and all I'm learning heaps. Wow!
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Re: The Infinite Cosmic Lattice

Postby Dave_Oblad on October 16th, 2012, 3:34 am 

Hi all,

I wrote:
Also, if the wavelength of light leaves a Galaxy Cluster and becomes stretched due to the expansion of space, then when it re-enters another Galaxy Cluster that isn't stretched (same rung lengths as the first one exited) then why doesn't the wavelength revert back to it's original wavelength? In other words, why does the wavelength only change (stretch) leaving a cluster but not (shrink) when entering another?

Forget that part.. it was a dumb brainfart..lol. I slipped into thinking about gravitational red shifting rather than expansion red shifting. The answer I would expect is that there will be some blue shift as light transitions from expanded space back to "normal space" but the accumulated red-shift expansion that was added up over a long time scale could still easily out weigh the minor blue shift. This observation will play a role coming up, but it was premature here. Sorry about that.

But the first part intended to tie the lattice to the planck length still stands and seems unavoidable.

Best wishes,
Dave :^)
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 16th, 2012, 2:19 pm 

Dave_Oblad wrote:Ok, so I took your perfectly symmetrical lattice and added some Galactic Clusters (not shown) following your rules that the lattice only stretches between Galactic clusters but not inside them. Given some semi-random placement of Clusters, your lattice becomes distorted as shown below:

Dave, my red cubes are superclusters, so it's large scale. What you have shown is "small scale" - I think that the whole of your 'lattice square' would fit inside one of my red cubes. The dynamics there are completely different. You are in effect showing gravitational spatial deformations of the overall flat space, like the 'rubber sheet' analogy, with some randomly places masses. Since we are talking about two different things, comments on some of your other remarks may be just confusing the issue here.

Also, if the wavelength of light leaves a Galaxy Cluster and becomes stretched due to the expansion of space, then when it re-enters another Galaxy Cluster that isn't stretched (same rung lengths as the first one exited) then why doesn't the wavelength revert back to it's original wavelength? In other words, why does the wavelength only change (stretch) leaving a cluster but not (shrink) when entering another?

Again, you are mixing gravitational and cosmological redshifts. In practice the two effects are added together, but remember that the gravitational blue shift of light entering a cluster is cancelled by the gravitational redshift when the light leaves the cluster. Further, the gravitational redhshifts are tiny when compared to the redshifts that we use in cosmology. There are also other effects when light passes through clusters and superclusters, but they are taken into consideration when the redshifts are measured.

A more significant issue is the Doppler shift when there are peculiar movements of the clusters, i.e. when my red cubes are actually moving relative to the blue bars that are directly around them. However, at the scales we are talking for the blues bars, it is quite insignificant (from observations). It becomes a problem only when we measure cosmological redshifts inside our own red cube, so to speak.

To summarize, the cosmological principles does not hold inside red cubes (clusters and superclusters) - and IMO, that is what you are depicting in your lattice. To reiterate, this thread is about the large scale, where we know that things are reasonably homogeneous and that the cosmological principles discussed w.r.t. the "infinite lattice" then hold as a close approximation.

Regards,
Jorrie
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Re: The Infinite Cosmic Lattice

Postby Dave_Oblad on October 16th, 2012, 10:20 pm 

Hi Jorrie,

Looks like you didn't get to see my brainfart retraction before you posted. Yes, I know the difference between Gravitational Red-Shifting and Universe Expansion Red-Shifting. My bad...lol. I feel so stupid I should go shoot myself ;-)

Anyway, I meant to take this in smaller steps, so if I may continue...

See.. I think we have a difference in our definitions of expanded distance, so I'm going to try and nail that down first.

Let's forget about the Clusters for a moment (pretend they are gone) and focus on the lattice. If I take a beam of light, let's say (frequency of) 500 nano-meters, and call that a single "Unit" of distance measurement. That the current distance between two rungs of the lattice is (let's say) 1 zillion (gotta love that number..lol) such Units.

We let enough time pass such that the distance has doubled between the rungs of the lattice due to expansion.

Now.. are you saying that there are 2 Zillion "Units" between rungs or that there is still 1 zillion (stretched) "Units" ?

Best regards,
Dave :^)
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 17th, 2012, 12:58 am 

Dave_Oblad wrote:Looks like you didn't get to see my brainfart retraction before you posted.

Hi Dave, yes, I wrote the reply over some period of time, since I was out of town and I saw your retraction when it was too late. Sorry about that. But I think other people may perhaps have found the retraction and correction educational. Smaller steps would be good for that as well.

Let's forget about the Clusters for a moment (pretend they are gone) and focus on the lattice. If I take a beam of light, let's say (frequency of) 500 nano-meters, and call that a single "Unit" of distance measurement. That the current distance between two rungs of the lattice is (let's say) 1 zillion (gotta love that number..lol) such Units.

We let enough time pass such that the distance has doubled between the rungs of the lattice due to expansion.

Now.. are you saying that there are 2 Zillion "Units" between rungs or that there is still 1 zillion (stretched) "Units"?

I was hoping my Part 2 on cosmic distances covered this question. Please reread that, but it is probably good to repeat some of it here. Cosmologist normally use either comoving or proper distances in their work. Comoving distance is equivalent to counting the number of lattice bars between two cubes and multiplying the count by the present length of the bars (all of the same length). I would shy away from the term "rungs" here, because this is terminology used in the so-called cosmological "distance ladder", which means something different. Dcomoving is the distance used in Hubble's law: the recession velocity of a distant galaxy Vrecession = H0 multiplied by Dcomoving. If one bar's two ends recede from each other at 70 km/s, then the two ends ends of 10 adjacent bars recede from each other at 700 km/s.

It is the proper distance D that doubles in your example, normally called Dthen and Dnow in the literature. Dthen relates to your "1 Zillion units" then and Dnow to your "2 Zillion units" now. Over 'smallish' distances like 100 million light years, all three distances are roughly the same, but they obviously have different values on longer distances in any form of expanding cosmos.

I must stress that without the cubes (superclusters) the whole thing is a bit troublesome, because how would we count the number of bars, or measure the stretch factor? OK, I suppose we can postulate putting light beacons with negligible mass in place of the cubes, so that we can still count bars and measure redshifts. This would be equivalent to the pure "compound interest" lattice of Part 3 above. Our present cosmos seems to be heading to such a mode again, as we said before.

Regards,
Jorrie
Last edited by BurtJordaan on October 17th, 2012, 3:49 am, edited 2 times in total.
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 17th, 2012, 3:38 am 

DragonFly wrote:Where are particles when they are 'between' the lattice?

I seem to have never directly answered this question. Essentially, particles like light and cosmic rays can be anywhere in the lattice. The only things that I restrict are the red cubes, which sit only at nodes. This is for the purpose of analogy and explanation. The real galactic structure is not arranged like this, but on a very large scale (remember my bars are one billion light years long), the cosmos seems to work just like this lattice analogy - the math and interpretation thereof are essentially identical.

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The Infinite Cosmic Lattice (Summary)

Postby BurtJordaan on October 17th, 2012, 7:48 am 

The insights, feedback, misconceptions and lessons learned by means of the 'infinite cosmic lattice' analogy are summarized here. It is a "toy-model" of the cosmos, sharing many characteristics with the real thing, provided of course that we assign certain dynamics to the lattice, e.g. that it expands.
BurtJordaan wrote:Image

I started off by saying "The red cubes represent the 'particles' of the perfectly flat, isotropic and homogeneous universe, while the blue bars are just distance markers." This was perhaps a bad choice of words, because the cubes really represent cluster galaxies, i.e. things bound by mutual gravitational forces that overwhelm the cosmic expansion. The blue bars represent space, but space is not limited to the bars, it is everywhere between the cubes.

The lattice is infinite by definition, in other words we are unable to detect any edge, no matter how well we observe. This does not mean that the real cosmos is infinite, but we have not been able to detect evidence of an edge so far, so we may conclude that it is large enough to be infinite for all practical purposes. The lattice started out infinitely large and hence is not expanding into anything. This is perhaps the most difficult thing to wrap one’s head around; the best is to just accept that there is always more outside of what we can possibly observe.

The real universe is not as evenly spread out, but when viewed at large enough scales, it resembles the uniform lattice. Even if individual blue bars do not have the same length, they have an average length and over a large number of them, the differences cancel out. This is exactly what we observe for the cosmos on the larger scales. The cubes are also not necessarily identical, just like clusters of galaxies are not identical, but again they have an average scale and mass. A proper large scale model of the cosmos that assumes this works amazingly well. It can predict just about everything that we observe on large scales.

I have conveniently hidden all the complexity of non-uniformity of the smaller scales inside the identical red cubes. Professional cosmologists do the same thing in order to get handles on the large scale picture. Once that is in place, they start to ‘look inside the cubes’ and try to figure out how that complexity influences the larger picture. I would appreciate if readers will also first get good ‘brain handles’ on the larger scale, before trying to probe inside cubes. The larger thing is complex enough as it is…

I have illustrated expansion by means of financial interest, both of the simple and compound variety. One can express investment interest rates in two ways: the straight percentage per time period or as a time required to double the investment. In a way the latter is more intuitive and I have used it in this thread as the Hubble time, which is exactly the time to double the present size of all the blue bars (or all current distances between pairs of superclusters), should the present compound interest rate be maintained. Presently it is between 12.5 and 14 billion years, depending on refinement of the measurement accuracy of certain cosmological parameters, which can never be perfect. The expected long term Hubble time is between 14 and 17 billion years, depending on the same refinements as mentioned.

It is sometimes confusing to newcomers when they hear that the expansion is accelerating, while the doubling time is going up, which means lower interest rate. The accelerating expansion is like the actual growth (say in $) every month in a compound interest investment. It can go up, while the interest rate is slowly dropping, provided that the interest rate does not drop too fast. In our present cosmos, the observed values are compatible with an actual growth that is faster than what the slowly dropping interest rate can cancel out. In the very early cosmos it was the other way round, i.e. the interest rate dropped fast enough so that the actual growth also dropped. This is why you may hear that the cosmic expansion is accelerating ‘in late times’.

We have also seen that the drop of cosmic growth rate (%) has to do with the density of radiation and matter. In the very early times, radiation density ruled supreme, but then the mantle quickly shifted to matter density that dragged down the expansion rate percentage. As the expansion ‘thinned’ these effects (less density), the drop in % interest became less and less, until the % will eventually stabilize in the future. Something that did cause some confusion is that the red cubes essentially retain their individual densities, but as the blue bars stretch, the overall average density drops.

To “prove” that the lattice is a good analogy of the real large scale cosmos, I have given two graphical representations; one for the lattice and one for the LCDM cosmic model. The latter is shown below.

Image

The only difference between the two graphs was that the vertical axis has been labeled “Years or kilometers” in the lattice case. You see what I mean?

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Re: The Infinite Cosmic Lattice

Postby Gregorygregg1 on October 17th, 2012, 11:08 am 

BurtJordaan wrote:No my lattice analogy represent an infinite cosmos, but I recognize that we do not have direct evidence for that. If the geometry is perfectly flat and it is not infinite, then there may be an end to it. We simply don't know. Hence, by Occam's razor, it is better to make it infinite. In practice it may be spherical though, finite with no edges.


Spherical within what context? Shape requires dimension. The universe is dimension. For the universe to have a boundary, that boundary must lie within itself. I don't have a problem with this concept. On the other hand it can only expand within itself. You propose there are places, " superclusters" where expansion does not occur. Does it not follow that there must also be areas where the lattice is shrinking to compensate for the expansion? In which case the average expansion might be closer to, say...zero?
I assume we are talking about the fabric of space. Here we are stretching space at a fairly rapid pace. Do you imagine the fabric gets thinner as space stretches? What happens when it snaps? Do the blue bars retract like the ends of a broken rubber band? I understand this is only a model, but I can't help seeing what happens when you play with it a little roughly.
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 17th, 2012, 12:41 pm 

Gregorygregg1 wrote:Spherical within what context? Shape requires dimension. The universe is dimension. For the universe to have a boundary, that boundary must lie within itself. I don't have a problem with this concept. On the other hand it can only expand within itself.

Cosmologists mean spherical in 4 spatial dimensions (not 3 space and one time). The 4th spatial dimension is sometimes called "hyperspace" - it is hypothetical in the sense that we do not know whether it exists or not. But in practice it means that if we could draw a large enough triangle in space and measure its inside angles, we would have found that they added up to more than 180 degrees. It would mean that there is an overall curvature to space itself. I do not deal with that in my lattice - it represents a flat space, where inside angles of triangles add up to precisely 180 degrees.

You propose there are places, "superclusters" where expansion does not occur. Does it not follow that there must also be areas where the lattice is shrinking to compensate for the expansion? In which case the average expansion might be closer to, say...zero?


Nope, not to such an extent that the average is zero - the average expands, that much we can measure. There are actually smaller scale areas and times where certain things shrink; otherwise, how could the red cubes have formed from loosely coupled gas and dust molecules?

I assume we are talking about the fabric of space. Here we are stretching space at a fairly rapid pace. Do you imagine the fabric gets thinner as space stretches? What happens when it snaps? Do the blue bars retract like the ends of a broken rubber band? I understand this is only a model, but I can't help seeing what happens when you play with it a little roughly.


Do not take the blue bars too literally. They are just space holders, improving visualization. So, do space get 'thinner' as it is stretched? As far as we know, not. Amazingly, it seems that space is not stretched, it simply 'grows', creating more space at the finest possible scale. This also explains to some extend why there is no need for an edge to space - "from within", as you said.
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Re: The Infinite Cosmic Lattice

Postby Dave_Oblad on October 17th, 2012, 11:46 pm 

Hi Jorrie,

Before I start, I should say that I see the Universe in very mechanical terms, perhaps even digital, since I'm a programmer. I was trying to understand the mechanics of Gravity and thus had to read everything I could on Relativity. It took some time to realize that Science didn't understand the Mechanics but rather had a good handle on predicting (and being correct) all aspects of masses and their gravitational effects on each other. I've a pretty good grasp now on the Mechanics of Gravity, which is why I cringe when I read or hear someone saying a body is pulling on another body.

Anyway, I fully embraced Einstein's "Fabric of Space-Time" very literally. Relativity makes perfect sense. But when I see the expanding model of the Universe I find myself in conflict with the concepts learned about Space-Time. It all boils down to the definition of expansion. I have no problem with variable density Space-Time. It makes sense that if the fabric of Space-Time is compressed (like around a black hole) and given that the fabric is continuous (unbroken), then when compressed due to the proximity of matter, it must stretch elsewhere, mostly between the Galaxies. But since the fabric controls everything and is directly related to the Planck Length, Then the speed of light is always constant, even if it appears not to be to a remote observer.

For example, in my perception, if you look at that distorted lattice that I last posted, you will find small squares and large squares. But a light beam will take the same amount of time to cross either. Locally, it's always a constant but a remote observer watching the front of a light beam will think that the beam is speeding up and slowing down, since they can't tell how stretched (or compressed) that section of Space-Time has become. For the same reason that the wavelength of light stretches as is leaves a Gravity well and shrinks when it enters another.. it's all a push and balanced. So when I see the fabric gets stretched between Galaxies, I see the same effect of balance when light stretches and re-compresses when exiting one Galaxy and entering another. Thus, the distance between Galaxies isn't really changing, other than their relative velocities to each other. Thus Doppler red-shift needs an alternate explanation, in my book anyway.

So that brings us to my last question, which you answered. But first, I want to be sure we are on the same page about the Fabric of Space-Time. I assume you agree that the void between Galaxies has structure and isn't just simply empty. If it had no structure, then there is nothing to work with..period.

So, if it has structure, then I wanted to clarify if you are talking about Stretching the Fabric, in which distance isn't increasing, based on the ruler of light. Or if you are adding to the Fabric of Space-Time. So my question was:

Let's forget about the Clusters for a moment (pretend they are gone) and focus on the lattice. If I take a beam of light, let's say (frequency of) 500 nano-meters, and call that a single "Unit" of distance measurement. That the current distance between two rungs of the lattice is (let's say) 1 zillion (gotta love that number..lol) such Units.

We let enough time pass such that the distance has doubled between the rungs of the lattice due to expansion.

Now.. are you saying that there are 2 Zillion "Units" between rungs or that there is still 1 zillion (stretched) "Units" ?


Your answer, if I understood you correctly, is 2 zillion. Or literally: That additional Fabric is being added all the time. Ok, that is consistent with why my Ladder (placed between two remote Galaxies) would be shattered as you stated. That would explain Doppler Red-Shifting very nicely.

But..

That means I have to accept that at times.. new Fabric is stitched into the current Fabric, in order to keep "Adding" to it. Ok.. since I see light as discrete packets of photons then the distance between packets can have some extra distance slices inserted between them on occasion, thus separating them by some real distance, thus dropping the measured frequency.. based on how often a new slice of Fabric is inserted between packets. Greater distance.. More time.. More slices inserted. Ok, Doppler Shifting makes sense now.

I am at a loss, however, on what kind of mechanical effect can actually stitch new Fabric into the existing Fabric, why it would, what triggers the event and what would happen if the sudden addition were to happen in the center of a photon? It would seem to me that it would shatter it's dance of symmetry and convert it to a bunch of component particle radiation. You know.. a bit like a man walking on stones across a pond and having a stone suddenly moved a bit further away, during a mid-step, causing the man to stumble and hurt himself.

(That would make the void a virtual mine-field to cross by those poor unsuspecting photons...lol)

It's equally hard to imagine this photon killing (adding new fabric) can only take place in deep deep deep space. Why can't new Fabric be added almost anywhere? What's so special about the Mechanics of Space-Time way out there.. that's not true locally?

Anyway, I just wanted to be absolutely clear that the Expansion of The Universe is based on adding new Space-Time Fabric to the existing Fabric and not just stretching the existing Fabric.

You wrote: Amazingly, it seems that space is not stretched, it simply 'grows', creating more space at the finest possible scale.

Yep.. pretty amazing indeed.

Now I have to think about the modulation effect of adding distance slices into a light beam at random intervals.. yikes.. my head hurts.

I gotta run now.. Catch you on the flip side.

Best Regards,
Dave :^)
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 18th, 2012, 7:53 am 

It makes sense that if the fabric of Space-Time is compressed (like around a black hole) and given that the fabric is continuous (unbroken), then when compressed due to the proximity of matter, it must stretch elsewhere, mostly between the Galaxies. But since the fabric controls everything and is directly related to the Planck Length, Then the speed of light is always constant, even if it appears not to be to a remote observer.


Yes, it is a way of looking at it, but not the only one. I prefer the curved spacetime view, where nothing is compressed or stretched. The math is the same for both cases, but one must not take either too literally, except perhaps to get one’s brain wrapped around it.

For example, in my perception, if you look at that distorted lattice that I last posted, you will find small squares and large squares. But a light beam will take the same amount of time to cross either. Locally, it's always a constant but a remote observer watching the front of a light beam will think that the beam is speeding up and slowing down, since they can't tell how stretched (or compressed) that section of Space-Time has become.


I cannot quite agree with “a light beam will take the same amount of time to cross either”. In the cosmology sense, light takes longer to cross larger patches of space, even locally. As I pointed out before, the lattice that you have shown represents one of my red cubes, so it is not cosmological. Your statement sounds more like the particle physics level, where light takes one Planck time unit to cross one Planck length unit. I do not think we must mix those two worlds in this thread.
Thus, the distance between Galaxies isn't really changing, other than their relative velocities to each other. Thus Doppler red-shift needs an alternate explanation, in my book anyway.


Well, I don’t think it works like that in the cosmologist's books. The proper distance between the galaxies are indeed increasing and light will take longer to pass between two superclusters. The spatial expansion stretches the wavelength of light; it is not quite a Doppler shift. Essentially, the expansion “cools” the photons, i.e. rob them of energy; hence the longer wavelengths.

It is however also correct to view the cosmological redshift as an ‘infinite’ number of normal Newtonian Doppler shifts through expanding space, where adjacent quanta of space have tiny Doppler shifts relative to each other, implying that they are locally moving relative to each other.

I have made the calculations where I take the cubes of my lattice to be only one Plank volume each and they are separated by one Planck length. Then I started to add the blue bars, one Planck length long and keep on adding Planck length sections to each. I then calculated the cumulative recession velocity between two red cubes and applied Newtonian Doppler shifts. Amazingly, I got exactly the standard cosmological redshift, indicating that one may use either interpretation. You have come to the same conclusion, I think.

I am at a loss, however, on what kind of mechanical effect can actually stitch new Fabric into the existing Fabric, why it would, what triggers the event and what would happen if the sudden addition were to happen in the center of a photon?


The only mechanism that we do understand, sort of, is Einstein’s original cosmological constant, Lambda. It is like the Gravitational constant (G), but it seems to work only on large distances. Essentially Lambda is a fixed spatial curvature that is built into the fabric of ‘empty’ space, just like G is a local curvature imposed by concentrations of energy, mainly of the E=Mc2 variety. At shorter distances G overwhelms Lambda and vice-versa for large distances.

How does Lambda create empty space? Nobody knows; maybe it doesn’t and it simply stretches existing space. This is the interpretation that I prefer.

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Last edited by BurtJordaan on October 18th, 2012, 11:47 pm, edited 1 time in total.
Reason: Minor correction
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Re: The Infinite Cosmic Lattice

Postby Gregorygregg1 on October 18th, 2012, 11:41 am 

BurtJordaan wrote:Well, I don’t think it works like that in the cosmologist's books. The proper distance between the galaxies are indeed increasing and light will take longer to pass between two superclusters. The spatial expansion stretches the wavelength of light; it is not quite a Doppler shift. Essentially, the expansion “cools” the photons, i.e. rob them of energy; hence the longer wavelengths.

My initial reservation about the expanding universe is not resolved. Whatever "shape" it may have in four, or even N dimensions, expansion means the universe is invading something. If the universe is everything, there is nothing but itself to invade.
I appreciate the way you think really big, Zillions and gazillions of light years. I tend to think a bit smaller. Now you have me cooling my photons to account for red shift. Expansion of gas reduces its energy. You imply the same effect on photons. With a gas adiabatic cooling occurs when the pressure of a substance is decreased as it does work on its surroundings. Expanding space is a different situation. Are you saying the expansion of space requires energy, and that at least part of that energy is stolen from light passing through it? Essentially you have expansion pirates waylaying your photons and forcing them to give up their energy or walk the Planck.
Is there anything in heaven or earth other than expansion that might account for cooling photons in your philosophy Horatio?
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 18th, 2012, 2:24 pm 

Gregorygregg1 wrote:My initial reservation about the expanding universe is not resolved. Whatever "shape" it may have in four, or even N dimensions, expansion means the universe is invading something. If the universe is everything, there is nothing but itself to invade.

This last sentence is the key. Why does it need anything to expand into if it has itself? The universe may or may not have extra dimensions, but it is not really necessary. As Dave_O and me have discussed, it is valid to think that "new space" is simply created in the empty areas (the voids), eventually pushing the red cubes apart.

Now you have me cooling my photons to account for red shift. Expansion of gas reduces its energy. You imply the same effect on photons. With a gas adiabatic cooling occurs when the pressure of a substance is decreased as it does work on its surroundings. Expanding space is a different situation.


Not that different, I would say. "Empty space" still contains some gas, dust and a variety of cosmic particles, apart from a few photons per cubic light year. If it expands, it cools. It is a bit technical to discuss the 'temperature of photons' here, so if you can live with the notion, good. Otherwise we can try to make it clearer.

Are you saying the expansion of space requires energy, and that at least part of that energy is stolen from light passing through it? Essentially you have expansion pirates waylaying your photons and forcing them to give up their energy or walk the Planck.


No, not quite. The energy of expansion comes from other sources. The photons simply lose energy due the expansion; they do not 'steal it from expansion', AFAIK. It is similar to the police car's siren; when it comes towards you, the sound hitting your ears is higher pitched and have more energy than when it moves away from you. You are not stealing energy from the sound waves; relative to you they simply have more energy or less energy, depending on the direction of movement of the source.

Hope this helps.
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Re: Infinite Cosmic Lattice (Part 2)

Postby Cancer on October 18th, 2012, 11:22 pm 

Hello, I am aware that this is an ongoing discussion that has been going on a while, however I am new to this forum and I do have one question...

What is the reason for which the blue lattice bars are expanding? Is this due to the expansion of the universe?

Thanks,
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 18th, 2012, 11:31 pm 

Hi Cancer, welcome to the forums. :)

Cancer wrote:Hello, I am aware that this is an ongoing discussion that has been going on a while, however I am new to this forum and I do have one question...

What is the reason for which the blue lattice bars are expanding? Is this due to the expansion of the universe?


Yes, the blue bars are part of empty space, just needed to visualize the 3D structure. So they "stretch" with the expansion of the universe. If you read my replies to Dave_O, you will get an idea of potential mechanisms that may cause space to expand.
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Re: The Infinite Cosmic Lattice

Postby Dave_Oblad on October 19th, 2012, 4:23 pm 

Hi Jorrie,

You're doing it again..

So they "stretch" with the expansion of the universe. If you read my replies to Dave_O, you will get an idea of potential mechanisms that may cause space to expand.

I put some effort into getting you to admit that Space_Time Growth is "Additive" and not "Stretching". There is a distinction.

For Example: The Balloon analogy of expanding space. If one draws a wavelength between pasted Galaxies on the balloon and blows more air into it.. you will see the wavelength passing between Galaxies both Stretch, Travel and Shrink.. in other words.. it's a net sum of zero. Exactly like how Gravity stretches/compresses wavelengths. (Hence, the premature brainfart I posted above.)

The correct Analogy is:
Imagine a ball of water floating in front of you. Imagine some Islands on the surface of this ball. Now imagine the effect of injecting more water into the ball to make it larger. Notice the Islands are moving apart. The speed of injection sets the speed of growth and the Islands move apart at some rate. Now you can use the Red-Shift Doppler Effect because the Islands really are moving further apart by the moment. Noting the relationship of changing distance between the closer Galaxies and further Galaxies.

My point being that there is a fundamental difference between stretching and compounding (adding to).

Since the Red-Shift effect is a direct function of the distance to a Galaxy and age of the light, this leaves two options for an explanation or interpretation of this measured and documented effect.

1). Adding to the Volume of Space-Time.
2). Tired light.

Number(1) seems problematic because one should have an explanation of where this extra "Stuff" is coming from, why & how it is integrated and why does it only appear in deep deep space and not between the stars inside a Galaxy.

Number(2) Light undergoes change through a series of accumulated errors relative to it's age increasing it's wavelength.

I'm inclined to lean towards the 2nd choice myself, given what we have to work with and what is the simplest.

Best wishes as always,
Dave :^)
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 19th, 2012, 5:03 pm 

Hi Dave
Dave_Oblad wrote:I put some effort into getting you to admit that Space_Time Growth is "Additive" and not "Stretching". There is a distinction.

But I have not admitted to that. All I said is that the two views are equivalent and both acceptable. I think I have also said that there is no operational way to settle it one way or the other by observation. I have it against a Doppler shift, because that's very confusing, because then you have to worry about what part of the redshift is Doppler due to peculiar movement and what is truly cosmological. In these cases there is a distinction.

My point being that there is a fundamental difference between stretching and compounding (adding to).


How would you know that without a way to discriminate by observation?

Number(2) Light undergoes change through a series of accumulated errors relative to it's age increasing it's wavelength.

I'm inclined to lean towards the 2nd choice myself, given what we have to work with and what is the simplest.


Observations seem to disfavor the tired light idea.

Wikipedia wrote:Additionally, the surface brightness of galaxies evolving with time, time dilation of cosmological sources, and a thermal spectrum of the cosmic microwave background have been observed — these effects that should not be present if the cosmological redshift was due to any tired light scattering mechanism.
Despite periodic re-examination of the concept, tired light has not been supported by observational tests and has lately been consigned to consideration only in the fringes of astrophysics.


Quantum cosmology may perhaps be able to answer these question some time. Until then, I find it good enough to be able to grasp what is happening, without worrying too much about the fundamental mechanism. I'll leave that to the quantum guys and girls.

In my valley it is getting late, so I'm signing out...
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Re: The Infinite Cosmic Lattice

Postby Dave_Oblad on October 19th, 2012, 6:10 pm 

Hi Jorrie,

Dave wrote: Anyway, I just wanted to be absolutely clear that the Expansion of The Universe is based on adding new Space-Time Fabric to the existing Fabric and not just stretching the existing Fabric.

Jorrie wrote:Amazingly, it seems that space is not stretched, it simply 'grows', creating more space at the finest possible scale.

Jorrie wrote:
Dave wrote:I put some effort into getting you to admit that Space-Time Growth is "Additive" and not "Stretching". There is a distinction.
Jorrie wrote:But I have not admitted to that.

Please refer to the center quote box above Jorrie..lol.

Anyway, I agree that when Quantum Mechanics is Unified with Relativity, we'll have a more complete picture of everything. And I'm still cheering for "Tired Light". Ok.. Wounded Light ;-)

Best to you always,
Dave :^)
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 20th, 2012, 12:32 am 

Hi Dave,

Here you go and play the game like the 'crackpots', which I am sure you are not a member of. ;-))
Dave_Oblad wrote:...
BurtJordaan wrote:Amazingly, it seems that space is not stretched, it simply 'grows', creating more space at the finest possible scale.

...
Please refer to the center quote box above Jorrie..lol.

It would have helped everybody if you have quoted in context:
BurtJordaan wrote:
Gregorygregg1 wrote:I assume we are talking about the fabric of space. Here we are stretching space at a fairly rapid pace. Do you imagine the fabric gets thinner as space stretches? What happens when it snaps? Do the blue bars retract like the ends of a broken rubber band? I understand this is only a model, but I can't help seeing what happens when you play with it a little roughly.

Do not take the blue bars too literally. They are just space holders, improving visualization. So, do space get 'thinner' as it is stretched? As far as we know, not. Amazingly, it seems that space is not stretched, it simply 'grows', creating more space at the finest possible scale. This also explains to some extend why there is no need for an edge to space - "from within", as you said.


Specific answer to illustrate a point, trying to cover a possible misconception about space getting "thinner", not an 'admission'. Stretch or "continuous creation" of space, one can take your pick, as long as you do not read too much into any one of them. In any case, the 'bleeding edge' of cosmology has a new view on things, called "emergent spacetime". It is still incomplete and far too advanced for this thread, perhaps even for this forum.

BTW Dave, I recall that you are a programmer; how is your HTML/Javascript experience? I have two cosmological calculators in this terrible, but ultimately portable web language in need of updating.

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Re: The Infinite Cosmic Lattice

Postby Gregorygregg1 on October 20th, 2012, 2:50 am 

Try this one. Imagine a giant blender about one quarter full of concentrated soap solution. When you turn on the machine not much happens right away, but pretty soon the top is off the blender and a mass of bubbles is headed across the counter toward the floor. Some of the bubbles are popping and others are getting bigger by sucking up the substance and air of the smaller bubbles. Expansion by inclusion! But of course this includes two ingredients, and your model of expansion has only one ingredient, and a pretty thin one at that. I can't help thinking your model has a missing ingredient.
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 20th, 2012, 2:57 am 

Gregorygregg1 wrote:Expansion by inclusion! But of course this includes two ingredients, and your model of expansion has only one ingredient, and a pretty thin one at that. I can't help thinking your model has a missing ingredient.

Try the cosmological constant, aka "dark energy". ;)
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Re: The Infinite Cosmic Lattice

Postby Gregorygregg1 on October 20th, 2012, 10:53 am 

BurtJordaan wrote:Try the cosmological constant, aka "dark energy". ;)

Let us suppose for a moment that there is such a thing as "Dark Energy". In order for it to support an accelerating expansion, wouldn't there have to be an ever increasing supply? This means that somewhere there is a dark energy generator. If the dark energy generator is dark mater, shouldn't it have been exhausted in production of dark energy? LCDM and dark energy are hypothetical. One could as easily say that dark energy is the breath of God inflating the universe balloon. I'll wait till they find the stuff before getting on that wagon.
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 20th, 2012, 12:24 pm 

Gregorygregg1 wrote: Let us suppose for a moment that there is such a thing as "Dark Energy". In order for it to support an accelerating expansion, wouldn't there have to be an ever increasing supply?

Einstein predicted it (the cosmological constant) almost a century ago and 80 years later we found something 'pushing' out there, just like Einstein postulated. If Einstein predicted a 'cosmic duck' to exist, supernovae showed us something that walks like a duck and the CMB something that quacks like a duck, chances are that there is a duck.

This means that somewhere there is a dark energy generator. If the dark energy generator is dark mater, shouldn't it have been exhausted in production of dark energy?


Present insights point us toward a 'duck farm'. In simple terms, the more space between the red cubes, the more duck there is, which again creates space even faster. It appears as if it's a property of space - every so many cubic units of space contains so many ducks that multiply (mildly) exponentially, needing more space...

However, the ducks are not made from dark matter, which is essentially confined to inside or directly around the clusters, not in the empty space. Dark matter clumps together, ducks don't. I think that the term "dark energy" is unfortunate - it used to be mysterious, but it is no longer quite so.

Granted, there are many details to be worked out and many more observations to be made, but that's the way of science. Point is, we simply do not have anything else that matches observations even closely as well as duck. We also have some idea of how the duck farm works.

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Re: The Infinite Cosmic Lattice

Postby Gregorygregg1 on October 20th, 2012, 12:42 pm 

Perhaps I'm taking your analogy too literally, but this sounds like a population curve. uncontrolled population growth results in a repeating sine curve: Lag phase, log phase, plateau and crash. You describe the universe as an infinite log phase. Is that correct? The duck farm needs no food for growth, but sustains growth with some endless supply of itself? If it quacks like a duck, it still needs corn.
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Re: The Infinite Cosmic Lattice

Postby BurtJordaan on October 20th, 2012, 1:05 pm 

Gregorygregg1 wrote: You describe the universe as an infinite log phase. Is that correct? The duck farm needs no food for growth, but sustains growth with some endless supply of itself? If it quacks like a duck, it still needs corn.

Indeed, but ducks just need the right real estate and they can live off nature. If the ducks have discovered my infinite lattice, their offspring do not even have to migrate over any major distances; their immediate real estate simply grows, since they don't live in the red cubes.
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PS: I guess that Dave_O will love this - ducks creating their own real estate where they are.
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Re: The Infinite Cosmic Lattice

Postby Gregorygregg1 on October 20th, 2012, 2:22 pm 

Emptiness eating emptiness to make more emptiness. Hey, leave those red cubes alone! ...Damn ducks.
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