Inflation and Element Formation: Irreconcialble?

[aboro]

I write this in the hope that somebody reading this can explain to me, a laymen, in non-mathematical, plain English terms, why my thinking is wrong regarding the calculation of the age of the observable Universe and the formation of the elements in the Periodic Table given the (short) age of the Universe.

I watch the TV series dealing with the Universe where astronomers say that the universe is about 14 billion years old. In the same breath, they also say that the light we see today coming through our telescopes on Earth left a distant galaxy just shy of 14 billion years ago. (let us assume for simplicity sake about 13.5 billion years ago). I will call that distant galaxy "Galaxy X". If my understanding of what they are saying is correct, this would suggest that the plasma/energy/ matter (or whatever label the scientists want to call it and which I will call "Stuff" for simplicity sake) which became Galaxy X and the Stuff that ultimately became the Earth (which, for simplicity sake, I refer to as "Earth-Stuff") both came into existence at the same time and from the same starting gate -- about 14 billion years ago.

Question #1: Assuming my understanding just discussed is substantially correct, how is it possible that the light we see today coming from Galaxy X took 13.5 billion years to reach us when the light which left that distant galaxy already had reached Earth-Stuff billions of years ago? It seems to me to be impossible for an observer on Earth to see the light from Galaxy X twice: the first time is when the (hypothetical) observer located on Earth Stuff observed that light about 14 billion years ago; the second time is when a present day observer on Earth saw that early light coming from Galaxy X while peering through a telescope.

Question #2: I understand that Expansion?Inflation of the Universe may answer my first question. As somebody on this Forum explained, the effect of Inflation/Expansion of the Universe is that even though Galaxy X and Earth-Stuff came into being at the same time about 14 billion years ago, Inflation/Expansion caused Galaxy X and Earth Stuff to become instantly separated (at an apparent speed faster than the speed of light) by a distance so great that it has taken the light from Galaxy X about 14 billion years to reach us today. But then how is it possible that the Earth today possesses all the elements in the Periodic Table? I ask this question based upon Cosmologists and physicists telling us that many of these elements came into existence through the death of earlier stars. If that is so and given that the age of the Earth is about 4 billion years old, it seems to me that there could not have been enough time for those earlier stars to come into existence and then die within a time frame that would allow the four-billion year old Earth to have the elements it has today.

I hope I have stated my question in a manner that does not cause many of the readers of this forum to throw their hands up in despair. I would appreciate those who have a far greater understanding of this to provide answers.

 

[marcus]

Hi Aboro,
I remember our earlier thread where you were thinking it is impossible for light from a star to take 13.4 billion years to get to us. I know you asked for a NON-MATH explanation, but I want to try something that is basically just arithmetic. No equations, no algebra.
I want to encourage you to learn to read this table:
(It has a lot of extra stuff you don't need to understand. Don't let that scare or confuse. I'll suggest what to focus on.)

$${\scriptsize\begin{array}{|r|r|r|r|r|r|r|r|r|r|r|r|r|r|r|r|} \hline a=1/S&S&T (Gy)&R (Gly)&D_{now} (Gly)&D_{then}(Gly)&V_{now} (c)&V_{then} (c) \\ \hline 0.091&11.000&0.4726&0.7105&31.447&2.859&2.18&4.02\\ \hline 0.106&9.469&0.5920&0.8894&30.231&3.193&2.10&3.59\\ \hline 0.123&8.151&0.7414&1.1130&28.920&3.548&2.01&3.19\\ \hline 0.143&7.017&0.9284&1.3922&27.509&3.921&1.91&2.82\\ \hline 0.166&6.040&1.1621&1.7401&25.990&4.303&1.80&2.47\\ \hline 0.192&5.199&1.4542&2.1728&24.357&4.684&1.69&2.16\\ \hline 0.223&4.476&1.8185&2.7087&22.602&5.050&1.57&1.86\\ \hline 0.260&3.853&2.2723&3.3685&20.721&5.378&1.44&1.60\\ \hline 0.302&3.317&2.8355&4.1732&18.711&5.642&1.30&1.35\\ \hline 0.350&2.855&3.5313&5.1413&16.574&5.805&1.15&1.13\\ \hline 0.407&2.458&4.3851&6.2820&14.316&5.825&0.99&0.93\\ \hline 0.473&2.116&5.4225&7.5870&11.954&5.650&0.83&0.74\\ \hline 0.549&1.821&6.6657&9.0202&9.516&5.225&0.66&0.58\\ \hline 0.638&1.568&8.1292&10.5121&7.046&4.494&0.49&0.43\\ \hline 0.741&1.350&9.8148&11.9676&4.596&3.406&0.32&0.28\\ \hline 0.861&1.162&11.7095&13.2878&2.224&1.915&0.15&0.14\\ \hline 1.000&1.000&13.7872&14.3999&0.000&0.000&0.00&0.00\\ \hline 1.162&0.861&16.0138&15.2745&2.081&2.417&0.14&0.16\\ \hline 1.331&0.751&18.1309&15.8712&3.784&5.036&0.26&0.32\\ \hline 1.524&0.656&20.3179&16.3092&5.321&8.110&0.37&0.50\\ \hline 1.746&0.573&22.5554&16.6216&6.693&11.686&0.46&0.70\\ \hline 2.000&0.500&24.8287&16.8396&7.910&15.820&0.55&0.94\\ \hline \end{array}}$$

For starters let's just talk about the FIRST ROW of numbers
the earliest stars I've heard about were very massive so they burned their fuel fast and had short lifetimes and then went supernova. Lifetimes on the order of a million years or a few million. they were from a time when distances were about 1/11 what they are today. That is why the label S=11 on that row. that top row is "first stars" and first puny little fuzzy blobby galaxies called "protogalaxies".

So try reading the first row. It tells you that the YEAR was year 473 million. Right? Do you see where it says what year it was? We can round off. Maybe it was 400, or 450 or 500 million. Precision is not important, just get a rough idea. TODAY by contrast, is year 13.8 billion. Do you see that down in the S = 1 row? S=1 means distances are exactly the size they are today, so it mean the present era.

What the table means by Dthen is the distance BACK THEN when the star emitted the light we are just now getting today. It is the socalled "proper" distance that astronomers use, which you would have measured if you could have gone back to that time (year 473 million) and stopped the expansion process long enough to measure by whatever conventional means e.g. radar. and then when you had measured you could have let expansion continue.

Do you see where it says that the distance from our matter, back then, was 2.86 billion LY?

This is Thing One. You are interested in the very earliest stars, that we are today getting light from.
They formed and sent us their light around year 470 million (the U had been expanding from its much more dense condition for about 470 million years, by then).
And when they formed and sent us the light we are getting today, they were at a distance of about 2.86 billion LY from the matter that eventually became our galaxy and our solar system, and us. That's how far they were from here, if you could have stopped expansion at that moment, long enough to measure by radar ranging or a long string or yardstick or whatever.

Let's stop here. Assimilate this much, just from the top row of the table. Let us know if you have any questions about the top row. does anything not make sense. Notice that there are speeds given, showing how fast the now distance and the then distance were growing. That could be thing two.

 

[cepheid]

I write this in the hope that somebody reading this can explain to me, a laymen, in non-mathematical, plain English terms, why my thinking is wrong regarding the calculation of the age of the observable Universe and the formation of the elements in the Periodic Table given the (short) age of the Universe.

I watch the TV series dealing with the Universe where astronomers say that the universe is about 14 billion years old. In the same breath, they also say that the light we see today coming through our telescopes on Earth left a distant galaxy just shy of 14 billion years ago. (let us assume for simplicity sake about 13.5 billion years ago). I will call that distant galaxy "Galaxy X". If my understanding of what they are saying is correct, this would suggest that the plasma/energy/ matter (or whatever label the scientists want to call it and which I will call "Stuff" for simplicity sake) which became Galaxy X and the Stuff that ultimately became the Earth (which, for simplicity sake, I refer to as "Earth-Stuff") both came into existence at the same time and from the same starting gate -- about 14 billion years ago.

Sure, the matter was there from the start. Galaxy formation happened later, but it began to happen fairly early on in the 13.7 billion year history of the universe.

Question #1: Assuming my understanding just discussed is substantially correct, how is it possible that the light we see today coming from Galaxy X took 13.5 billion years to reach us when the light which left that distant galaxy already had reached Earth-Stuff billions of years ago?

It hadn't already reached "Earth stuff" billions of years ago. The light from the most distant objects that we can see has only just arrived (for the first time). It has had only just enough time to reach us given the age of the universe.

It seems to me to be impossible for an observer on Earth to see the light from Galaxy X twice:

He didn't. There is only one "first" arrival time for the light, and at all subsequent times, light is continuously arriving.

the first time is when the (hypothetical) observer located on Earth Stuff observed that light about 14 billion years ago;

Again, why do you think that this happened? It didn't.

Question #2: I understand that Expansion?Inflation of the Universe may answer my first question.

Just call it expansion. In cosmology, "inflation" refers to something else very specific.

As somebody on this Forum explained, the effect of Inflation/Expansion of the Universe is that even though Galaxy X and Earth-Stuff came into being at the same time about 14 billion years ago, Inflation/Expansion caused Galaxy X and Earth Stuff to become instantly separated (at an apparent speed faster than the speed of light) by a distance so great that it has taken the light from Galaxy X about 14 billion years to reach us today.

Yes.

But then how is it possible that the Earth today possesses all the elements in the Periodic Table? I ask this question based upon Cosmologists and physicists telling us that many of these elements came into existence through the death of earlier stars. If that is so and given that the age of the Earth is about 4 billion years old, it seems to me that there could not have been enough time for those earlier stars to come into existence and then die within a time frame that would allow the four-billion year old Earth to have the elements it has today.

How is 10 *billion* years not enough time for earlier stars to be born, live, and die?

Perhaps you are thinking of the fact that since the estimated lifetime of our sun is 10 billion years (5 billion of which have already gone by), this would allow for, at most one generation of stars prior to the present one? There are a few things to keep in mind:

- one generation of stars would still have produced heavy elements
- there was, in fact, more than one generation of stars prior to the present one. Not all stars have the same lifetime. Stars more massive than our sun live for much shorter times (hundreds of millions of years or less). And these more massive ones are the ones that explode as supernovae, producing the heaviest elements and spreading them out widely.
- The first generation of stars, which astronomers refer to as "Population III" stars, would have been different from the ones that are forming now. Because they would be made from raw materials that have *no* heavier elements (only hydrogen and helium), it is actually expected from theoretical models that they would be able to achieve higher masses and hence be much shorter lived.

http://www.universetoday.com/24776/what-were-the-first-stars/

 

[Chalnoth]

Question #1: Assuming my understanding just discussed is substantially correct, how is it possible that the light we see today coming from Galaxy X took 13.5 billion years to reach us when the light which left that distant galaxy already had reached Earth-Stuff billions of years ago? It seems to me to be impossible for an observer on Earth to see the light from Galaxy X twice: the first time is when the (hypothetical) observer located on Earth Stuff observed that light about 14 billion years ago; the second time is when a present day observer on Earth saw that early light coming from Galaxy X while peering through a telescope.

Why would you think that an observer sitting near the matter that would eventually form into the Earth would be able to see that galaxy that long ago? Galaxies that far away would have likely been outside of our horizon 13.5 billion years ago, and would only become visible much later.

For some real numbers, see here:
http://www.astro.ucla.edu/~wright/CosmoCalc.html

An object whose light we're seeing today has taken 13.5 billion years to reach us would have a redshift of about z=21. Its distance when it emitted the light we're seeing today would have been about 1.64 billion light years, but we would have only been able to see about 0.44 billion light years out at that time, due to the very fast expansion rate back then. So the light from this galaxy did not reach us early-on, and we only became able to see the galaxy later due the fact that the expansion rate has slowed considerably in that time.

 

[mathman]

But then how is it possible that the Earth today possesses all the elements in the Periodic Table? I ask this question based upon Cosmologists and physicists telling us that many of these elements came into existence through the death of earlier stars. If that is so and given that the age of the Earth is about 4 billion years old, it seems to me that there could not have been enough time for those earlier stars to come into existence and then die within a time frame that would allow the four-billion year old Earth to have the elements it has today.

Earliest stars were formed about 500 million years after the big bang. They were big and burned out fast. They gave rise to all the elements other than those created immediately after the big bang (H, He, Li). 9 billion years (time between first stars birth and solar system birth) is plenty of time for element formation.

 

[aboro]

Marcus, Cepheid, Chalnoth and Mathman, I am fortunate indeed to receive your replies. While I have read them, I need time to comprehend them as well. Please give me some time to do that. Thanks to all of you.

 

[Reed Burkhart]

Hi Aboro, et al.

Your question seems to me to be a very good one, Aboro.

Would I be correct in summarizing it thusly:

If all in the universe today started from the void with a big bang, AND started from a single point exploding matter into existence outward from that point, then wouldn't it be necessary that either the sky would be dark (because no outward motion could exceed the speed of light) or there must be either motion or universe expansion at a rate faster than the speed of light?

Does that reasonably explain your question? (It sounds like a good question to me.)

If it does, then it seems the key follow up question is what is the difference between an expanding universe and the motion of an object in that universe - that we could say one of these could exceed the speed of light yet the other could not exceed the speed of light? It seems to me that there must be a phenomenological difference (including a verifiable description of the mechanism) for a) an expanding universe and b) for motion in a universe, before it would be reasonable to accept an argument based on differentiating such two suspect ideas. Since I am not a physicist, but am interested in these concepts, I wonder if the physicists might help me as well with Aboro's question, by explaining the two mechanisms for a) an expanding universe and b) for motion in a universe, and provide the empirical evidence relied on with regard to such a phenomenological differentiation.

By the way, Aboro, I have read some very recent alternative explanations for Hubble's observation that dimmer stars have more optical frequency shift (which seems to be the basis for the expanding universe conjecture). One comes from Yijia Zheng's research at the Chinese Academy of Sciences (arXiv:1305.0427 and arXiv:1306.1015, and perhaps others), where Zheng refers to empirical observations of photons losing energy by coupling with plasma (being absorbed into an electron and then re-emitted at every-so-slightly lower energy). Of course lower energy is lower frequency, so another way of looking at what Zheng is considering is as a simple frequency conversion as is done in every single radio device (cell phones, am/fm radios, satellite television, they all use frequency mixing to accomplish frequency downconversion). Then, redshift of dimmer stars can be explained simply because the dimmer (further) stars encounter more plasma mixing on their way from their origin to Earth. In this scenario, there seems to be no need of an expanding universe ... although monetary inflation seems to be unavoidable, at least for now!

 

[cepheid]

If all in the universe today started from the void with a big bang, AND started from a single point exploding matter into existence outward from that point, then wouldn't it be necessary that either the sky would be dark (because no outward motion could exceed the speed of light) or there must be either motion or universe expansion at a rate faster than the speed of light?

This is exactly the wrong way to think about the big bang (and is a common misconception, because of the name). The big bang was not an explosion of matter outward from a single central point into a pre-existing space. Rather, the big bang marked the beginning of the existence of space and time itself, and the expansion of space outward. There is no single central point, but rather every point expands away from every other point in a way that appears completely isotropic and homogeneous (which is consistent with our observations of the universe on the largest scales). We have a cosmology FAQ thread on this:

Where did the big bang occur? (Hint: everywhere at once)
https://www.physicsforums.com/showthread.php?t=506991 (third and fourth paragraph especially)

You might also find our (enormous) thread on the balloon analogy helpful, although it is a bit unfocused:

https://www.physicsforums.com/showthread.php?t=261161

If it does, then it seems the key follow up question is what is the difference between an expanding universe and the motion of an object in that universe - that we could say one of these could exceed the speed of light yet the other could not exceed the speed of light? It seems to me that there must be a phenomenological difference (including a verifiable description of the mechanism) for a) an expanding universe and b) for motion in a universe, before it would be reasonable to accept an argument based on differentiating such two suspect ideas. Since I am not a physicist, but am interested in these concepts, I wonder if the physicists might help me as well with Aboro's question, by explaining the two mechanisms for a) an expanding universe and b) for motion in a universe, and provide the empirical evidence relied on with regard to such a phenomenological differentiation.

Superluminal expansion is not inconsistent with special relativity, because no object is moving faster than light in any observer's inertial reference frame. No one is "catching up to a light beam." There is a dicussion of this in this paper:

http://arxiv.org/abs/astro-ph/0310808

AND we have an FAQ thread on this:

Can the expansion of space be faster than light?
https://www.physicsforums.com/showthread.php?t=508610

By the way, Aboro, I have read some very recent alternative explanations for Hubble's observation that dimmer stars have more optical frequency shift (which seems to be the basis for the expanding universe conjecture). One comes from Yijia Zheng's research at the Chinese Academy of Sciences (arXiv:1305.0427 and arXiv:1306.1015, and perhaps others), where Zheng refers to empirical observations of photons losing energy by coupling with plasma (being absorbed into an electron and then re-emitted at every-so-slightly lower energy). Of course lower energy is lower frequency, so another way of looking at what Zheng is considering is as a simple frequency conversion as is done in every single radio device (cell phones, am/fm radios, satellite television, they all use frequency mixing to accomplish frequency downconversion). Then, redshift of dimmer stars can be explained simply because the dimmer (further) stars encounter more plasma mixing on their way from their origin to Earth. In this scenario, there seems to be no need of an expanding universe ... although monetary inflation seems to be unavoidable, at least for now!

This is not a new idea, it is just a variant of the old "Tired Light" hypothesis, which is easily shown to be false by observational data:

http://en.wikipedia.org/wiki/Tired_light

We also have a couple of cosmology FAQ threads somewhat related to that:
Could redshift be intrinsic rather than due to expansion? (Hint: no)
https://www.physicsforums.com/showthread.php?t=506994

What evidence is there for the big bang model? (hint: it's much more comprehensive than just redshift alone)
https://www.physicsforums.com/showthread.php?t=506993

EDIT: Also, saying that "dimmer stars show more optical frequency shift" and that "this is the basis for the expanding universe conjecture" is wrong for two reasons:

1. Cosmological redshift only applies to very very distant objects, i.e. other galaxies. So you should really be saying that galaxies appear redshifted, not stars. Every star that we can observe *individually* is within our own galaxy, and none of these are expanding away from us, because our galaxy is a gravitationally-bound system

2. Redshift alone is not the sole basis for the "expanding universe conjecture" (which is way more than just a conjecture at this point). Expansion of the universe is predicted/explained by General Relativity and supported by a whole host of observations: the existence and the blackbody spectrum of the CMB, the abundance of the light elements (produced by big bang nucleosynthesis), to name just a couple. See the last FAQ above.

 

[Reed Burkhart]

That's a lot of information : ).

So the big bang is a bit like Hilbert's Hotel? Even though all space is already occupied it can still fit more?

The point Aboro made that caught my attention is the apparent incongruity between conjecturing expansion as causing the observed frequency downshifting vs. what seems a necessarily concomitant superliminal velocity -- if ever "H" is positive in the equation v = HD. No matter if one conjectured the big bang as suddenly appearing at one time and throughout all space (Hilbert's Big Bang, say) or if one conjectured the big bang from a single point in time and space, that apparent incongruity seems to be one that continues to need attention. There appear to be a number of reference papers which seem to consider the issue far from closed on the side supporting expansion, and the frequency downshifting of the Pioneer 6 spacecraft 's telemetry when the telemetry path was near tangential to the Sun's surface seems to be a remaining problem of explanation that so far has better explanations by such as Zheng's soft-photon process, no? I am just beginning to get a feel for these issues. But I am always reluctant to buy into a decided theory when there are many dissenters (as there appear to be here), when observations are of such distant and complex phenomena, and when reports only use a few examples measurements in attempt to support a theory that one would expect to show rather universal consistency.

I wonder if the expansion is supposed to be uniform? What mechanism would make the expansion non-uniform I wonder?

These are the questions that come up for a newcomer to the topic like me. They have probably been well worked over by the veterans.

The thing that strikes me as positive from the soft-photon theory of Zheng is that it would permit for a great variance in the v = HD behavior (and I have seen some charts which showed such variance, but it doesn't seem easy to find the raw data by just googling around). Do you know where a lot of good raw -- totally unfiltered, or nearly unfiltered -- data might be? So much becomes clear by just looking at data.

I have seen an article about twin (or is it binary?) stars, making the relatively obvious point that they should have the same average cosmological redshift if that is what was occurring (perhaps that was Zheng too, but maybe someone else), but the average redshift is different for each of the two stars. That makes no sense to me if it were primarily cosmological (i.e., expansion based) redshift involved. I wonder if others have found any good review papers on that topic?

I did find one review paper -- but I haven't really been focused on this topic too much, and there are surely many more. But the first one I happened into (arXiv:0707.1350) did little to impress that things were anywhere near as settled as I infer some profess. But I wonder if that's really such a big deal that there is a bandwagon orthodoxy effect ... I mean, without some degree of certainty expressed (even if overcertainty) it would probably be hard to justify the largest sums to invest in experiments. I suppose the main risk is that the experiments might look at the wrong thing (from not having duly considered all the angles ... found something there recently w.r.t. the DST mistake in space physics, which frankly relates to the redshift issue potentially, because the soft-photon process may involve the type of plasma interactions which Zwicky had proposed might exist, but which appear to be rather complex affairs to study).

Thanks, Mentor (whomever individual/s that may refer to), for some initial pointers. If you had any further points on where to find evidence that easily disproves the two papers by Zheng I referred to, that would be nice to know about, because his papers look pretty sound on an initial read. Zheng uses the phrase "reasonable tired light theory" -- so I infer he is aware that some tired light theories are unreasonable. I wish Zheng had been more explicitly to differentiate what he felt was reasonable vs. unreasonable (any guesses anyone?).

I'll be interested to try to understand your assertion that, "Superluminal expansion is not inconsistent with special relativity, because no object is moving faster than light in any observer's inertial reference frame. No one is "catching up to a light beam." There is a dicussion of this in this paper:", because as I think of it, my reference frame extends to infinity as does yours (is that true? maybe my assumption is false), and if so then surely any galaxy at a distance of c/H or greater away from me (where c is the speed of light and H is the Hubble constant) will -- according to the expansion theory -- be going faster than light in my reference frame, no? That seems like some rather simple math that would be hard to get around with some fancy theory ... but I am probably missing something, and I haven't yet read your references on that, which I look forward to doing (but if you could manage a simple explanation for your statement, rather than needing to go to the references, ... or is it too complicated to put in a paragraph or two? Thanks!).

The Hilbert Hotel image on the Big Bang is a new one for me, that I'll have to see what others have said about it. Many people take issue with the Hilbert Hotel "paradox" because it seems to permit adding more to infinity ... which on the face does seem a bit problematic ... and I would suspect that people would have made similar objections to the Big Bang theory then along the same lines (have they?) ... that if the universe suddenly came into being at the time of the big bang and already filled all space, that it wouldn't have any room to expand into!

Your help is immense, Mentor, thank you. Do you happen to recommend which research scientists or theoreticians or papers presenting the strongest case against big bang or expanding universe? It's sometimes good to look at various perspectives to see which portions of the argument of each seem to have the greatest integrity. So much to learn. So little time!

 

[aboro]

Marcus, I do have questions regarding the Table.

Question 1: If I understand the Table correctly, Row 1 says that Galaxy X (“GX”) and Earth Stuff (“ES”) were separated from each other by a distance of 2.6 Gly when the U was just 473 million years old. Is it accurate for me to say, therefore, that when T = 0, the distance between GX and ES also had to equal zero?

Question 2: Assuming your answer to Question 1 is yes, is it also accurate for me to say that within a mere 473 million years, a phenomenon cosmologists call “Expansion” caused GX and ES to become separated by a distance of 2.6 Gly?

Question 3: Assuming your answer to Question 2 is yes (and Reed, this may be germane to your post as well), is it correct for me to conclude that the rate of expansion between GX and ES is not the result of these two objects moving away from each other at a speed greater than c but by the creation of space (“Space Creation”) between these two objects such that light traveling at c takes longer to get from one point to another? I believe that you or somebodies like you who loves to teach others analogized the concept of Space Creation to a jogger who is able to run at a constant speed of 10 miles per hour. Even though the distance between the points of start and finish is 20 miles, it nevertheless took the jogger 24 hours to get to the finish line because he was required to spend time running (at 10 mph) on a tread mill resulting in him needing 24 hours to get to the finish line whereas he would only have needed 2 hours to do that if he was not hampered by the tread mills.

Question 4: Assuming I am understanding the Table correctly, the rate of expansion between GX and ES went from 2.6 Gly when U was 473 million years old to 5.8 Gly when U was 4.4 billion years old, i.e., an increasing rate of expansion. Am I correct in concluding that a deceleration thereafter occurred as shown by the following row which says that the distance between GX and ES was 5.650 Gly when T = 5.4225?

Question 5: Assuming your answer to Question 4 is yes, can you please explain what phenomenon caused the deceleration?

Question 6; I know that I may now be off-topic but if your answer to Question 4 is yes, I was under the impression that the Universe was expanding (perhaps caused by the presence of dark energy). If that is so, how can the deceleration discussed in Question 4 be reconciled with an observed rate of an expanding Universe?

Marcus, I have other questions but before I get too far afield, it would be great if you answer the ones I have framed.

I am still assessing the posts given by Cepheid and others to this tread.

Thanks!

 

[Drakkith]

So the big bang is a bit like Hilbert's Hotel? Even though all space is already occupied it can still fit more?

I prefer not to think in terms of "new" space being added, but instead think of it in terms of increasing distance between everything.

 

[Reed Burkhart]

I am aware of no mechanism ever observed with such capability. Can you help me there?

Whether or not augmented space comes diffusively or at the perimeter, conservation of space seems at issue with big bang (Hilbert Hotel). But that doesn't mean there is a problem if space isn't conserved. Is there a mechanism or evidence where space is not conserved?

There has been one line of thinking surrounding the various levels of physical observations being emergent from other levels (with infinities in between) whereby recursive mathematical forms (fractals, more or less) may populate all levels of space. If mechanisms were all dependent on such relationship, then any oscillation in the underlying generator functions could be imagined to produce spatial nonconservation. While I have read some theories of fundamental fractal physics, they are likely far from any mainstream physics, and I am not sure where either has offered any mechanism description for expansion (but I am suspecting there are mechanistic descriptions somewhere, I have not spent very much time at all looking). Unless one gets to either mathematical theory or mechanistic description (the two can be rather equivalent, especially once at a small enough scale) it is hard to imagine any reasonable differentiation between space expanding and objects moving -- the effect then perhaps being indistinguishable, there has not been any dealing with the issue of big bang conflicting with faster than light motion, no?

 

[Drakkith]

The two effects are indistinguishable as far as I know. And no, FTL due to the expansion of the universe doesn't conflict with anything. The recession velocity of an object can be anything, even far beyond c, as there is no global speed limit in GR, only a local one.

 

[Reed Burkhart]

What doesn't make sense to me about that is that local and global are a continuum in the sense that there is no definitive defining point beyond which the state "local" is no longer "local".

So to me it does not compute to say that "around here things can't go the speed of light" but that "over they they can go the speed of light", because over there is really no different than around here, because "around here" is in this place (0) or a step away (1), or n+1 for any n already in the set, so "around here" extends indefinitely in any direction.

It seems a false pretext to posit speed limits nearby but no speed limits further away, or to posit that far away and nearby are somehow different in their fundamental potentiality for certain phenomena (all other things being equal). Could you fill me in on how to get around that without inconsistency? Else one is left with the conflict, it would appear, that Aboro has asked about, no?

 

[aboro]

Cepheid, you say that "It hadn't already reached "Earth stuff" billions of years ago. The light from the most distant objects that we can see has only just arrived (for the first time). It has had only just enough time to reach us given the age of the universe."

--- it seems to me that your response can only be understood if one assumes that an expansion of the Universe occurred which therefore caused the light from Galaxy X, i.e., the galaxy we recognize today as the most distant object, to reach us today. Without the concept of expansion coming into play, it seems to me that the first light from Galaxy X reached Earth Stuff about 13.5 billion years and therefore out telescopes would not be able to capture that first light since it is now billions of years past us. Am I missing something?. that "first light" is now billions of light years beyond us and is not capable of being seen by our telescope agoexplanation nt objects had to have reached Earth Stuffthe instant the Universe came into existence. Without expansion at inception,

You also say "How is 10 *billion* years not enough time for earlier stars to be born, live, and die?
Perhaps you are thinking of the fact that since the estimated lifetime of our sun is 10 billion years (5 billion of which have already gone by), this would allow for, at most one generation of stars prior to the present one? There are a few things to keep in mind:

- one generation of stars would still have produced heavy elements
- there was, in fact, more than one generation of stars prior to the present one. Not all stars have the same lifetime. Stars more massive than our sun live for much shorter times (hundreds of millions of years or less). And these more massive ones are the ones that explode as supernovae, producing the heaviest elements and spreading them out widely.
- The first generation of stars, which astronomers refer to as "Population III" stars, would have been different from the ones that are forming now. Because they would be made from raw materials that have *no* heavier elements (only hydrogen and helium), it is actually expected from theoretical models that they would be able to achieve higher masses and hence be much shorter lived."

-- Thanks, Cepheid, for framing the issue this way. You are correct when you say I was erroneously assuming that all stars have a life expectancy similar to the sun. They don't.

 

[aboro]

I prefer not to think in terms of "new" space being added, but instead think of it in terms of increasing distance between everything.

Drakkith, assuming that 2 objects are not moving relative to each other, what is the difference between the creation of new space between these 2 objects and the "increasing distance between everything." It seems to me that these two concepts are the same. Am I missing something from your explanation?

 

[aboro]

What doesn't make sense to me about that is that local and global are a continuum in the sense that there is no definitive defining point beyond which the state "local" is no longer "local".

-- Cepheid, it seems to me that Reed's comment (which I also share) begins to make sense only if we take into account the creation of new space that is forming between two distant objects such that the laws of motion and light speed are valid for conditions existing in or near that object but break down or become inapplicable when the two objects are assessed relative to each other.

 

[aboro]

Drakkith, please ignore my query in post # 16. You answered that question in post # 13.

 

[Reed Burkhart]

... and if the space is expanding throughout space, then 1 angstrom away could also be not local and have faster than light motion ... no? (i.e., expanding universe, to me, seems not to hold up to scrutiny without some deeper and more fundamental and described mechanism ... it seems like a story to patch up observations in physics for which no good story has yet emerged ... which is why I've been inclined to look at Zheng's work, et al., for alternative explanations without what seem to be the problems attendant to expanding universe/big bang theory ... but N.B., I am no expert in these areas)

 

[cepheid]

Cepheid, you say that "It hadn't already reached "Earth stuff" billions of years ago. The light from the most distant objects that we can see has only just arrived (for the first time). It has had only just enough time to reach us given the age of the universe."

--- it seems to me that your response can only be understood if one assumes that an expansion of the Universe occurred which therefore caused the light from Galaxy X, i.e., the galaxy we recognize today as the most distant object, to reach us today. Without the concept of expansion coming into play, it seems to me that the first light from Galaxy X reached Earth Stuff about 13.5 billion years [ago?] and therefore out telescopes would not be able to capture that first light since it is now billions of years past us. Am I missing something?. that "first light" is now billions of light years beyond us and is not capable of being seen by our telescope

I added an "ago" to your quote. Did you mean to have one there? If not, then I do not understand the sentence.

Let's simplify the situation. Let's suppose that the universe is finite in age (13.7 billion years) but it is static, rather than expanding. Let's suppose also that that it is infinite (spatially), meaning that it has no boundaries. So all the matter (and space) in the universe somehow came into being 13.7 billion years ago, and formed into galaxies "shortly" thereafter. These galaxies are all (more or less) at fixed distances from each other (ignoring small local motions through space due to gravitational interaction). So, you're wondering, how could we only just be receiving the "first light" from Galaxy X now when it has had almost 13.7 billion years to reach us? Shouldn't the first light have long ago reached the location where Earth is now? Answer: it depends how far away Galaxy X is in this hypothetical static universe. If Galaxy X is only 3 billion light years away, then obviously its light first began to reach Earth long ago (only 3 billion years after the beginning). The light from it that is just arriving now left 3 billion years ago. So we are seeing that Galaxy as it was 3 billion years ago, not how it was when it first formed. On the other hand, if Galaxy X is now 13.7 billion light years away, then light from the clump of matter from which it formed is now only *just* arriving today. If Galaxy X is 40 billion light years away, then its light still hasn't reached us, and we cannot see it. So, in this hypothetical static universe, there is a sphere of radius 13.7 billion light years centred on us that contains everything we can see. We cannot see beyond this distance, because light from objects at those farther distances have not yet had time to reach us in the age of the universe. We call this volume the *observable* universe. And the really cool thing about it is that the farther out into the observable universe that you look (in distance), the farther back in time you are looking. You see images of nearby objects as they were recently. You see an object half-way across the distance of the observable universe not as it is now, but as it WAS at the halfway mark of the history of the universe. You would see an object right at the edge of the observable universe as it was right at the beginning of time.

The real situation in our expanding (not static) universe is similar to what I described above, except that the radius of our *observable* universe is even larger. It's some 46 billion light years, even though the age is only 13.7 billion years. The reason for this is that the universe is expanding. So: consider light from Galaxy X that is only just reaching us now for the first time. When that light left that object, it's formational clump and "Earth stuff" were very close together indeed. But the *present* distance of that object is very large, due to the expansion. So, there is no longer as obvious a relationship between the time it has taken for light from an object to reach us (for the first time) and its distance. I think these are the kinds of ideas marcus was trying to familiarize you with with his table. Defining distances to objects in an expanding universe is tricky. At least, you have to consider the distance of the object then (when it's light first left), the distance now (when the light first arrives) and the distance you would infer from the light travel time, which is not the same as either of the other two.

-- Cepheid, it seems to me that Reed's comment (which I also share) begins to make sense only if we take into account the creation of new space that is forming between two distant objects such that the laws of motion and light speed are valid for conditions existing in or near that object but break down or become inapplicable when the two objects are
assessed relative to each other.

Have you read the Cosmology FAQ thread on "faster than light" expansion? It's the fourth link I put in post #8.

 

[Chronos]

Zheng appears to be a dubious source and his 1306.1015 paper offers little in the way of original content. He relies heavily on ancient data and Paul Marmet as his sources. Marmet is quite the character. He not only championed plasma cosmology, but, was an outspoken critic of the big bang and Copenhagen interpretation of quantum mechanics. Zheng appears to have made liberal use of this paper by Marmet: 'Non-Doppler Redshift of Some Galactic Objects' [re: http://www.Newtonphysics.on.ca/doppler/] . According to the footnote: 'This above paper gives updated information about a previous corresponding analysis in: IEEE Transactions on Plasma Science Vol., 18 No: 1 February 1990, Pages 56-60.' I was unable to find a free version of the original IEEE paper. I assume they are quite similar.

 

[Reed Burkhart]

I am new here to PF, so am getting used to the pace and nature of interaction.

I am not surprised to hear something is dubious in advanced space physics, given my reading of it -- which is very limited, but which is guided by a sense reminiscent of Feynman's sage advice, something like, "Anyone who says that they understand Quantum Mechanics does not understand Quantum Mechanics". It seems to me that space physics is the hardest of all sciences, due to how remote the subject matter is.

So when you say that Zheng appears to be a dubious source, I am interpreting that as meaning you think his papers are dubious -- which you comment on in generalities, and that he has relied on prior work. To the extent that -- naturally I'd say -- a great plurality of people seem by nature to align to one way or thinking or another way of thinking about a thing, so follow a line of thinking; it seems like there is no support to a paper being a dubious source by the mere fact that it follows a certain line of reasoning, because that's the way scientific papers work ... they reference supporting arguments, perhaps (no?).

The very existence of any unsatisfactory aspects of what appears perhaps to be an orthodoxy, like the very existence of any unsatisfactory aspects of what appears to be a heterodoxy, both could lead one to suggest a source was dubious and relying on unoriginal arguments.

What I gather about your comment is that you are scientifically opposed to plasma cosmology? I have only scanned a few papers about plasma cosmology and am trying to come up to speed on the truth about redshift -- not willing to accept any orthodoxy or heteordoxy before studying it, understanding it, and agreeing with it, myself.

(I have also found some recent evidence through independent secondary research that may support plasma cosmology, in fact my discoveries led me to suspecting that redshift might be something akin to a frequency mixing and frequency downconversion process by light mixing with a special form of highly-intercoupled plasma, that might be, in fact, "dark matter" ... I have this work in a long draft manuscript form, and it touches on redshift and a couple other topics in advanced physics to which I am unfamiliar, where I present my conjectured connections so that I may begin to Bird-Dog the correct answers through communication with domain experts, orthodox and heterodox alike ... btw, I'd be happy to share my draft manuscript with others for a review of it and comments ... my focus in it is not on redshift, but another phenomena entirely, but one that is rather slippery, i.e., little data and possibly with some conflict to orthodoxy, so I have tried several different angles to advance sound insights and inferences).

I am rather new to all of cosmology, plasma physics, and the relevant disciplines -- and even to Zheng's work -- and so am finding an interesting time of engaging various experts in dialogue to learn opinion and science.

Of course, as I am sure everyone discussing scientific theories (as is done here on PF) will be aware, the hard part always is sorting out which is opinion and which is science!

I tried to look for the particular paper that Marmet footnotes in the paper you link. I found something related from a similar time period so may be reflective of Marmet's ideas at that time ( http://www.worldnpa.org/pdf/abstracts/abstracts_1075.pdf ). But there is a rather lengthy body of work with many conjectures on Redshift out there -- which to me today are ALL of a somewhat dubious nature, mostly because I haven't worked through enough of them to come to a sense myself of where the greater reason holds.

Observing human nature to look for something familiar, and then the occasional conceptual inertia, I can imagine that Hubble's and others' first suspicions would go with Doppler like explanations (not sure how much was known about dark matter at the time, which is what I am wondering about now ... whether or not dark matter interaction with light might explain frequency downconversion ... anyone know any articles about that?), and I can imagine that working out to a first order, given how simple a model it is ... and that the general nature of the phenomena seemed more or less of the right aspect.

But the more I read, the more questions or observations appear to have emerged to question the Doppler-like view (is the Doppler-like view considered orthodoxy today? ... it seems like perhaps that it is), but evidently not yet amassing a sufficiently simple and obvious alternative to dislodge the essentially Doppler argument (with Aboro, it seems too, and I seeking to understand what justification is made for saying there is any difference between motion as the familiar motion and motion due to an expansion ... starting myself from a totally skeptical position that one could perhaps differentiate between the two either observationally or theoretically).

What I like about this topic, is that it seems to offer sufficient evidence that conjectures can be made, yet that those conjectures do not appear yet -- from my current, initial, level of surveying the literature -- to have found a happy medium (consensus ... at least one that satisfies rigor, as I see it): so I infer there may be something new here potentially yet to be learned by science at large.

Intriguingly, my extension of an original analysis (of my own on a different tpoic) to the realm of cosmology came when asking the question, "if this strange phenomena [the one my analysis on a different topic studied] is happening in the near Earth space and also in the solar system, then what, if anything, might I be able to learn from considering any cousin phenomena to it in interstellar and intergalactic space?" Looking at that question from the perspective of one investigating redshift empirical observations and associated conjectures for the mechanism involved (including the expanding universe conjecture or others), might lead one to consider there might possibly be some new information relevant to redshift in my draft manuscript (on what was originally ... well and perhaps still, but who knows ... a totally unrelated topic) -- so I would offer for others to review that new manuscript of mine (although I am not yet posting it openly on the web, as it is still in early review) if they were interested. Perhaps email me if you're game for reviewing a rather lengthy manuscript: burkhart@alumni.caltech.edu

Btw, Chronos, in trying to understand where you are coming from as authority on redshift, I looked up your profile (first time to do that for anyone here on PF, as I am brand new here), and see you have a background in engineering. I really like that, because engineers have a degree of real world practicality to their work which isn't always -- in my personal experience -- reflected in the ivory towers (as beautiful and wise as they may be) where we may have learned our science and the principles behind our engineering work. In fact, I was working on a practical engineering like issue of trying to determine the relationship between satellite anomalies and sunspot cycle (are the satellite anomalies more numerous during solar sunspot max or solar sunspot min) that led me to looking at all the things anticorrelated to sunspot cycle (because empirical evidence shows satellite anomalies are anticorrelated to sunspot cycle, which is slightly heterodox to the notion of the greatest energetic activity from the Sun occurring in synchronism with solar sunspot maximum, and no one had really offered any compelling explanations for a solar sunspot minimum anomaly mechanism that could explain the anticorrelation of satellite anomalies to solar sunspot cycle so I began studying all that). It turns out that there are a huge number of things anticorrelated to solar sunspot cycle, and that the space physicists had neglected looking into that -- which seems self-evidently directly correlated to their making their self-confessed "DST mistake" (can give anyone references if interested, but you can google "DST mistake" to read about it as well).

The upshot of my work is a suspicion that dark matter in the solar system MAY (**POSSIBLY**) be involved in modulating or causing all these sunspot anticorrelated effects, and, if so, then perhaps a similar form of dark matter will cause frequency downshifting of light in intergalactic space (as well as in the solar system). It's only a tiny jump from there to a conjecture that dark matter could be involved in redshift, which is what has me beginning to look into expansion theory and redshift, in particular the observational evidence wherever I can find it, and in particular the observational evidence of the various forms (they do not appear to be of unison nature) of plasma redshift proponents (although none of the papers I have read yet that invoke plasma effects have treated the plasma effects quite as a frequency mixing process in the plasma, and there could be, I expect, some very challenging subtleties in quantum entanglement in the dark matter form which I've hypothesized, that I call Heavy Coupled Plasma/HCP, which may explain why there might not be a large, or even any appreciable, degree of scattering of the light, but mainly just a downconversion ... again all tentative and conjectural ... but you got to start somewhere on tracking down a new bit of information and what it seems to point to ... ). So thanks for both your sharing insights on this, and also your open mind ... there may be factors regarding redshift that are just coming into view today that have to do with dark matter and entanglement and frequency conversion ... who knows!

 

[Chronos]

I studied astrophysics as an undergrad, but, ended up an engineer. The job prospects seemed more realistic. I have, however, maintained my interest in all things cosmological throughout life and would even dare claim to be well read. I am not an authority on anything. No nobels, prestigious physics awards, or even a peer review published paper. BTW, the total amount of dark matter in the solar system has already been constrained to less than a planetary mass. It would otherwise mess with planetary orbits.

 

[Reed Burkhart]

Some insights while working on this leads to a conjecture that the Earth is the first node of a HCP plasma wave resonance. It's a rather simple equation that just seems too coincidental to me --

( (0.85 x 3E5 km/s) / 1.3 mHz ) / 1.31 = 149.6 million km (Earth's average orbital radius)

Where:
0.85 is a factor to give the wave velocity (subluminal, but relativistic)
3E5 km/s is approximately the speed of light
0.85 x 3E5 km/s is the wave velocity
1.3 mHz (or 0.0013 Hz) is a key resonance frequency of solar plasma, found in the solar wind, in the near Earth region, et al. (but coming from the Sun)
1.31 is a factor between the wave path along a Parker spiral arc (i.e., along a magnetic field line of the Sun)
149.6 million km is indeed the average radius of Earth orbit

Just earlier today I listened to one of the famous physicists of today mentioning (but not detailing) that dark matter is involved in holding Earth and Moon in their orbits. It appears to me to be potentially relatively easy to explain as an HCP node. (There is an even easier formulation for the Moon's orbital radius, if you're interested in my conjecture there.)

I want to be careful not to distract too much from Aboro's original topic here. Evidently this all could be interlinked, but -- it seems you've been contributing here for some time Chrono, so please help guide -- there are a number of subtle and slightly different topics. The main reason for MY interest in Aboro's question is to see if there is validating evidence and theory coming from cosmology vis a viz redshift and expansion theory that a form of highly intra-coupled plasma may be present and producing certain effects. So that, evidently, goes to the expansion/big-bang vs. other (including perhaps plasma redshift, but others too it seems) dialogue. Getting back to the original question: I still wonder if anyone has a description (or referenced description) for the mechanism which could justify observational or theoretical differentiation between an object relatively-receding in an expanding universe vs. merely relatively-receding due to traditional motion, and -- absent such solid description (and evidence!) do not expansion/big-bang seem hollow conjectures when they would demand (due to v = HD) that at any distance beyond c/H (speed of light divided by Hubble constant) that one of science's most firmly held principles (maximality of light speed) would become in conflict? Thanks, anyone!

 

[Chronos]

According to the literature, plasma cosmology was discredited by the mainstream about 20 years ago. It was also placed on the banned topics list by PF about 5 years ago. That is why I mentioned Zheng is an overt plasma cosmology sympathizer. I did not, and still do not feel any further discussion is necessary, or appropriate.

 

[Reed Burkhart]

So much to learn. I read about banned topics when I joined. Hmmmm ... will have to look into that elsewhere so as not to compromise Aboro's questions here!

 

[Chalnoth]

Drakkith, assuming that 2 objects are not moving relative to each other, what is the difference between the creation of new space between these 2 objects and the "increasing distance between everything." It seems to me that these two concepts are the same. Am I missing something from your explanation?

Yes, the two descriptions are basically the same. The increase in distance is a creation of new space.

 

[Drakkith]

What doesn't make sense to me about that is that local and global are a continuum in the sense that there is no definitive defining point beyond which the state "local" is no longer "local".

So to me it does not compute to say that "around here things can't go the speed of light" but that "over they they can go the speed of light", because over there is really no different than around here, because "around here" is in this place (0) or a step away (1), or n+1 for any n already in the set, so "around here" extends indefinitely in any direction.

It seems a false pretext to posit speed limits nearby but no speed limits further away, or to posit that far away and nearby are somehow different in their fundamental potentiality for certain phenomena (all other things being equal). Could you fill me in on how to get around that without inconsistency? Else one is left with the conflict, it would appear, that Aboro has asked about, no?

Think of it this way.

Velocity due to expansion is proportional to distance, with every megaparsec adding about 70 km/s worth of recession velocity. So at 1 megaparsec, an object traveling at 299,791 km/s away from us through space is traveling at 1 km/s under the speed of light. However, due to expansion, it will actually be traveling at 69 km/s over c. We will never see an object a 1 megaparsec receding at anything over 299,862 km/s, as that would require a velocity through space greater than c. So there's still a speed limit, it just depends on the distance and the rate of expansion.

Make sense?

 

[aboro]

Velocity due to expansion is proportional to distance, with every megaparsec adding about 70 km/s worth of recession velocity. So at 1 megaparsec, an object traveling at 299,791 km/s away from us through space is traveling at 1 km/s under the speed of light. However, due to expansion, it will actually be traveling at 69 km/s over c. We will never see an object a 1 megaparsec receding at anything over 299,862 km/s, as that would require a velocity through space greater than c. So there's still a speed limit, it just depends on the distance and the rate of expansion.

Make sense?

Drakkith, though what you say in response to Reed's query makes sense (at least for me), on what basis, thereflore, are we able to say anything regarding events and objects that are greater than 13.5 Gly away given that the light generated from those objects are beyond our ability to detect?

 

[Drakkith]

Drakkith, though what you say in response to Reed's query makes sense (at least for me), on what basis, thereflore, are we able to say anything regarding events and objects that are greater than 13.5 Gly away given that the light generated from those objects are beyond our ability to detect?

The observable universe is over 46 billion light years in radius. This corresponds to a light travel time of about 13.3 billion years. That means that the region of space that emitted this light 13.6 billion years ago is now 46 billion light years away due to expansion. (at the time of emission it was only millions of light years away) Since we are looking into the past the further we see, there is literally nothing to see past this point because 13.6 billion years ago corresponds to the emission of the CMB. Prior to this point in time the universe was opaque to EM radiation. Therefor we cannot make observations about anything past 46 billion light years.

 

[aboro]

I added an "ago" to your quote. Did you mean to have one there? Yes. If not, then I do not understand the sentence. You did understand the sentence

The real situation in our expanding (not static) universe is similar to what I described above, except that the radius of our *observable* universe is even larger. It's some 46 billion light years, even though the age is only 13.7 billion years. The reason for this is that the universe is expanding.

But if I understand correctly from the Table Marcus included in post #2, it appears that the Universe started to decelerate when it was about 5.4 billion years old. Do we know what caused the deceleration to occur? How is this deceleration reconciled with what is today regarded by the cosmological community as an “expanding” universe?


Have you read the Cosmology FAQ thread on "faster than light" expansion? It's the fourth link I put in post #8.

I just did. Thanks for calling it to my attention. This subject is drop-dead interesting.

 

[marcus]

But if I understand correctly from the Table Marcus included in post #2, it appears that the Universe started to decelerate when it was about 5.4 billion years old. Do we know what caused the deceleration to occur? How is this deceleration reconciled with what is today regarded by the cosmological community as an “expanding” universe?

Hi Aboro, it seems to me now that I blundered when I posted that table. Too much unexplained info for now. I think Cepheid and some of the others are engaging very successfully with your questions and probably I should just be quiet ("too many cooks" what you don't need is more distraction! just keep focused on a single question and quiz people until you understand.) Probably best just to ignore the table in my post #2.

 

[marcus]

However…this is such an interesting thread that I simply cannot resist jumping in! I really like your question about the MAXIMUM in the D_then column! It doesn't mean the universe reaches a maximum size and then shrinks. D_then is not the size of the universe, it's more interesting than that.

We can classify galaxies by how much their light waves have been stretched by the time we receive them. That gives a handle on when it was they emitted the light which we are receiving from them today. D_thenis the distance that galaxy was back then when it emitted the light.

You noticed a MAXIMUM in the row labeled S=2.458, also labeled a=0.407 (this is just the reciprocal 1/S).
Let's round off for convenience and say S = 2.5, and a = 0.4.

If you see a galaxy with your telescope and you determine that its waves have been stretched by a factor of 2.5 then it emitted the light back when DISTANCES WERE 40 PERCENT what they are today. And the table tells you all kinds of stuff about that galaxy.
How far from our matter it was when it emitted the light (Dthen) and how far it is now (Dnow) and how fast it was receding then, and now, and HOW OLD the universe was at that that moment when the light was emitted.

$${\scriptsize\begin{array}{|r|r|r|r|r|r|r|r|r|r|r|r|r|r|r|r|} \hline a=1/S&S&T (Gy)&R (Gly)&D_{now} (Gly)&D_{then}(Gly)&V_{now} (c)&V_{then} (c) \\ \hline 0.091&11.000&0.4726&0.7105&31.447&2.859&2.18&4.02\\ \hline 0.106&9.469&0.5920&0.8894&30.231&3.193&2.10&3.59\\ \hline 0.123&8.151&0.7414&1.1130&28.920&3.548&2.01&3.19\\ \hline 0.143&7.017&0.9284&1.3922&27.509&3.921&1.91&2.82\\ \hline 0.166&6.040&1.1621&1.7401&25.990&4.303&1.80&2.47\\ \hline 0.192&5.199&1.4542&2.1728&24.357&4.684&1.69&2.16\\ \hline 0.223&4.476&1.8185&2.7087&22.602&5.050&1.57&1.86\\ \hline 0.260&3.853&2.2723&3.3685&20.721&5.378&1.44&1.60\\ \hline 0.302&3.317&2.8355&4.1732&18.711&5.642&1.30&1.35\\ \hline 0.350&2.855&3.5313&5.1413&16.574&5.805&1.15&1.13\\ \hline 0.407&2.458&4.3851&6.2820&14.316&5.825&0.99&0.93\\ \hline 0.473&2.116&5.4225&7.5870&11.954&5.650&0.83&0.74\\ \hline 0.549&1.821&6.6657&9.0202&9.516&5.225&0.66&0.58\\ \hline 0.638&1.568&8.1292&10.5121&7.046&4.494&0.49&0.43\\ \hline 0.741&1.350&9.8148&11.9676&4.596&3.406&0.32&0.28\\ \hline 0.861&1.162&11.7095&13.2878&2.224&1.915&0.15&0.14\\ \hline 1.000&1.000&13.7872&14.3999&0.000&0.000&0.00&0.00\\ \hline 1.162&0.861&16.0138&15.2745&2.081&2.417&0.14&0.16\\ \hline 1.331&0.751&18.1309&15.8712&3.784&5.036&0.26&0.32\\ \hline 1.524&0.656&20.3179&16.3092&5.321&8.110&0.37&0.50\\ \hline 1.746&0.573&22.5554&16.6216&6.693&11.686&0.46&0.70\\ \hline 2.000&0.500&24.8287&16.8396&7.910&15.820&0.55&0.94\\ \hline \end{array}}$$

You are very observant, I believe, to have noticed that Dthen maximum in the S=2.5 row!
Of course it is not the size of the universe. It is the distance that a very special galaxy was from us at a very special moment (or more exactly that special class of galaxies whose light was emitted when distances were 40% of today's size and whose light arrives more reddish because wavelengths enlarged by factor S=2.5.)
Each row of table tells you about a different class of galaxies.

And if the row has S much bigger than 11 then it tells you not about light from stars and galaxies but about the heat-glow of hot gas that has not formed stars yet.

Aboro, did you notice the special row S=1 ?
That is the row for what we would see with no wave stretch at all. Where the light we receive today from something was emitted today and there is essentially no change in wavelength.
In other words S=1 denotes the PRESENT.

So naturally the distance is zero! Because we are seeing the thing as it is today. Dthen in that row equals Dnow, both distances are the same and both are zero.

 

[cepheid]

The real situation in our expanding (not static) universe is similar to what I described above, except that the radius of our *observable* universe is even larger. It's some 46 billion light years, even though the age is only 13.7 billion years. The reason for this is that the universe is expanding.

But if I understand correctly from the Table Marcus included in post #2, it appears that the Universe started to decelerate when it was about 5.4 billion years old. Do we know what caused the deceleration to occur? How is this deceleration reconciled with what is today regarded by the cosmological community as an “expanding” universe?

Hi aboro,

The universe has always been expanding: the separation between any two particular objects has always been increasing with time. When we say that the universe has been "decelerating" or "accelerating", what we mean is that the expansion has been "slowing down" or "speeding up." So, it is a statement about the rate of the expansion. In the beginning, the universe began expanding rapidly, but then that expansion slowed with time. In the relatively recent past, this trend reversed itself, and the outward expansion began to speed up.

EDIT: You asked what caused the deceleration to occur, initially. Although the physics of this is determined by General Relativity, a complicated theory, you can get some intuition for it even from high school level physics and the simpler gravitational theory of Newton. In Newtonian gravity, everything with mass exerts a force on everything else with mass, and we call this force gravity. So, if you take a bunch of objects and throw them outward away from each other in all directions, you would expect their outward motion to be slowed due to the mutual gravitational attraction of those objects. This is what cosmologists expected: that the expansion should be ever slowing down due to the mutual gravitational attraction of all the matter in the universe. In the mid 90s, astronomers discovered that this was not the case: it is actually speeding up. Newtonian gravity cannot explain this. It was a super shocking and unexpected discovery: like as if you threw your keys in the air, and instead of gravity slowing down their upward motion, that upward motion got faster and faster and the keys accelerated away from you, escaping. However, General Relativity can explain this, with something that can be fairly naturally added to the equations called "the cosmological constant."