[Bored chemist]

So what is the real size of the entire Universe?

Why did you put the word "so" in there?

[Halc]

Despite this being a reply to Dave, I am posting this mostly to readers who actually care about what some of these numbers mean. I know that Dave will continue to post things that conveys a lack of reading comprehension of this information.

Yes, we can measure the Hubble constant.
and it is constant everywhere.

It is not constant anywhere. It is approximately 1/t where t is cosmological time, and being a function of time, it is continuously changing, not a constant at all.

https://www.researchgate.net/figure/The-Hubble-diagram-or-the-velocity-distance-relation-plot-for-type-Ia-supernovae_fig1_331983227
The Hubble diagram or the velocity-distance relation plot for type Ia supernovae

They don't say how they measure distance in that graph. There are many ways to do so, and they're approximately the same only for nearby objects. That graph goes only to about 2 billion light years away, so yea, it doesn't matter much. But we see galaxies much further away than that, and distances become meaningless without specification of coordinate system used.  My example object is GN-z11, a very distant galaxy. Some typical choices:

1) Inertial coordinates: Only in inertial coordinates is light speed a constant c, and the coordinate system only applies to space that is more or less Minkowskian (flat), which is not true at large scales. In such coordinates, light can get from anywhere to anywhere else given enough time. There are no event horizons. The Milne solution uses such coordinates. Using such coordinates, the current size of the entire universe (relative to the inertial frame of Earth) is a sphere of radius about 13.8 BLY. Distances are measured along lines of simultaneity in the chosen frame. GN-z11 is about 13.5 BLY away, and the light we see now was emitted 6.7 BY ago.

2) Proper distance, comoving coordinates: This is the only coordinate system where H0 is meaningful. There is no maximum speed for anything, so there is no problem with objects at arbitrarily large separations after finite time. Distances are proper distance (measured by adjacent comoving rulers at a given time) traced on lines of constant cosmological time.
GN-z11 is a proper distance of about 31 BLY away and the light we see now was emitted 13.2 BY ago from only about 2 BLY away. Light from sufficiently distant events will not reach us due to acceleration of expansion forming event horizons.

3) Comoving distance/coordinates: In these coordinates, light speed is a function of time (c/scalefactor). Most objects (galaxies) are reasonably stationary and their distance is fixed since the big bang. Distances are proper distance (measured by adjacent comoving rulers at the current time) traced on a line of 13.8 BY cosmological age.
GN-z11 is a proper distance of about 31 BLY away and the light we see now was emitted 13.2 BY ago from a comoving distance of about 31 BLY.  Light from sufficiently distant events will not reach us due to dark energy slowing light speed to the extent that it can never reach us.

4) There is also the dubious light-travel distance, which isn't a valid coordinate system at all, but declares the distance to objects to be c/t from emission event. Light from GN-z11 was emitted from about 13.2 BLY away as measured by light travel time.

The velocity-distance relation plots for freely expanding gas molecules (Figure 2 to Figure 6) are exactly like the velocity-distance relation plot for the receding large-scale structures according to the Hubble diagram; the molecules receding slowly are closer to us whereas the molecules receding faster are further away from us.

That's nice, but the model is Newtonian and doesn't work at all at scales approaching visible universe distances, let alone distances beyond that.

Hence, at any distance and at any direction from us the Hubble constant is always 70 (km/s)/Mpc.

No. Only at events at similar cosmological time to us, which reduces the applicability of the value to coordinate systems 2 and 3 above.

Therefore, the value of Hubble constant should exists at any location in the entire infinite universe.

Again, no. Only to events at similar cosmological time to us.

Hence, if we could jump to a point that is located at 10BLY from us

Ambiguous statement without coordinate system. Using for instance inertial coordinates, jumping to a point located 10 BLY away gets you to a galaxy where the Hubble constant is currently measured at perhaps 100 km/sec/mpc, not 70. This is why choice of coordinate system matters.

we would find that any galaxy that is located in the visible universe of that point has exactly the same Hubble constant.

If you used comoving coordinate system, then you can choose a galaxy a trillion LY away and H0 will currently be measured at 70 there, just like here. There are no galaxies that far away in the inertial coordinates, not in our frame anyway. In a different inertial frame, yes, you can get galaxies at any distance you want, but H0 will not currently be 70 there.

1 Trillion years away and even in the infinity LY away

Infinity is not a distance or a size or a number. Much of your nonsense assertions stem from using it like it was a number. BC has pointed this out. Yes, you can talk about a galaxy a trillion LY away, at least if you use an appropriate frame.

Therefore, as 1/H0 is the calculated age of the Universe, then the age of the entire infinite Universe is 13.8 BY.
Hence, 13.8 BY ago, just after the Big Bang and the inflation the size of the entire infinite Universe was at the size of "grapefruit".

So very wrong. Nobody said that. You keep (seemingly deliberately) dropping the adjective 'visible' from 'universe'. I have a hard time believing anybody is this stupid, so it just means you're trolling when you make nonsense statements like that.
The visible universe was about the size of a grapefruit shortly after inflation. It was much smaller before inflation, but the Hubble 'constant' is entirely inapplicable until after inflation. The universe expanded at an exponential rate during inflation, but only at an approximately linear rate thereafter.

Therefore, as long as we all agree that the Hubble constant is equal everywhere - the Big bang should create our current infinite universe from a single bang.
There is no other option!

There are other options, which is why these things are 'unknown', and essentially do not matter.

Is it possible for the Big Bang to form Infinite Universe in a single bang that took place 13.8 By ago?

You just said that was the only option, and now you're asking if it's even possible. Go figure...

[Kryptid]

Hence, As you go further back in time, the density of all matter increases and the "bubble" that represents our observable the entire infinite Universe gets smaller.

An infinitely-large Universe can't become smaller if all of space is shrinking at a finite rate.

[Dave Lev (OP)]

It is not constant anywhere. It is approximately 1/t where t is cosmological time, and being a function of time, it is continuously changing, not a constant at all.

Yes, it is changing over time, but today it is constant everywhere.
In the following article it is stated:
https://www.forbes.com/sites/startswithabang/2019/08/02/sorry-astronomy-fans-the-hubble-constant-isnt-a-constant-at-all/?sh=555468819d59
"the "Hubble constant" itself is a misnomer. It has a value today that's the same everywhere in the Universe"
So what is the meaning of everywhere?

That graph goes only to about 2 billion light years away, so yea, it doesn't matter much.

Why do you limit the "everywhere" to only 2 BLY?
Don't you agree that everywhere means - the entire universe even if it is in the size of one trillion LY or just infinite?
Therefore, do you confirm that the current Hubble constant everywhere in the entire universe should be 70?
If you still think that the above statement is incorrect - then would you kindly prove it by other article?

The visible universe was about the size of a grapefruit shortly after inflation. It was much smaller before inflation, but the Hubble 'constant' is entirely inapplicable until after inflation. The universe expanded at an exponential rate during inflation, but only at an approximately linear rate thereafter.

That explanation from the BBT is very clear.
However, I still don't understand why do you insist that only the visible / observable universe was in the size of the grapefruit shortly after inflation?
Do you finelly confirm that as of today the Hubble constant is constant everywhere in the entire universe (even if it is infinite)?
Based on the BBT calculation for Hubble constant there is no limit in the size of the Universe.
So, why do you insist that only the observable universe can fit into that grapefruit size?
Why not "everywhere"?

An infinitely-large Universe can't become smaller if all of space is shrinking at a finite rate.

Yes, I fully agree with this understanding.
However, don't you agree that it proves that there is a severe contradiction between the BBT calculations from that Hubble constant to our understanding?
Therefore, why can't we look for better option for our understanding?

There are other options, which is why these things are 'unknown', and essentially do not matter.

Could it be that you say this message as you do understand that there is a contradiction?
If thinks are unknown, then could it be that the current theory isn't fully correct or just incorrect?
Why do you refuse to consider other options?

[Kryptid]

However, it proves that there is a severe contradiction between the BBT calculations from that Hubble constant to our understanding.

No, it doesn't and I don't understand why you think it does.

[Dave Lev (OP)]

However, it proves that there is a severe contradiction between the BBT calculations from that Hubble constant to our understanding.

No, it doesn't and I don't understand why you think it does.

You have stated that:

An infinitely-large Universe can't become smaller if all of space is shrinking at a finite rate

I assume that you mean that an infinitely-large Universe can't become smaller if all of space is shrinking at a finite rate at a given time.
However could it be that infinitely-large Universe can become smaller if all of space is shrinking at a finite rate in infinite time?
So, why can't we just release the cosmic time?
https://en.wikipedia.org/wiki/Cosmic_time
"The current physical cosmology estimates the present age as 13.8 billion years"
Is there any possibility for us to look again on all the current observations/measurements without the BBT glass/filter?

[Kryptid]

However could it be that infinitely-large Universe can become smaller if all of space is shrinking at a finite rate in infinite time?

No, because such an infinitely-large Universe doesn't have some kind of boundary that can get smaller in the first place.

So, why can't we just release the cosmic time?

What do you mean by "releasing" cosmic time?

Is there any possibility for us to look again on all the current observations/measurements without the BBT glass/filter?

You can, but so far the Big Bang theory is still the best candidate for explaining the observations.

[Halc]

I know that Dave will continue to post things that conveys a lack of reading comprehension of this information.

How true this prediction already turned out to be.

Yes, it is changing over time, but today it is constant everywhere.

If you had actually comprehended my prior post, it say that which events constitute 'today' is frame dependent, and relative to Earth's inertial frame (the frame which you seem to imply), it is very much a different value at distant places 'today'.

"the "Hubble constant" itself is a misnomer. It has a value today that's the same everywhere in the Universe"
So what is the meaning of everywhere?

If you had actually comprehended my prior posts, this question has already been answered. It is literally every location in space, no matter how distant.

That graph goes only to about 2 billion light years away, so yea, it doesn't matter much.

Why do you limit the "everywhere" to only 2 BLY?

If you had actually comprehended my prior post, you'd realize that I did not mention 'everywhere' in that sentence. It was a comment about the graph you linked, not about 'everywhere'.

do you confirm that the current Hubble constant everywhere in the entire universe should be 70?

The universe consists of more than today, but H would be measured at 70 by comoving observers at events where the age of the universe and gravitational potential are both reasonably the same as here. This would not be true of distant events 'today' relative to Earth's inertial frame since such events do not meet the criteria above.

However, I still don't understand why do you insist that only the visible / observable universe was in the size of the grapefruit shortly after inflation?

I don't insist on it. I said estimates vary, but that's the approximate size that best explains empirical observations.

Based on the BBT calculation for Hubble constant there is no limit in the size of the Universe.

No, not based on that at all. The Hubble constant is not a function of the size of anything. If you had actually comprehended repeated prior posts by myself an others, you'd stop asking this.

So, why do you insist that only the observable universe can fit into that grapefruit size?

It fit into a lot smaller space than that. That's simply how very much it had grown by the end of inflation epoch.

Could it be that you say this message as you do understand that there is a contradiction?

Not if none has been identified. I only see you contradicting your own assertions, but not that of the BBT. It's like insisting that 2+2=4 is contradictory because you don't know the largest integer.

I assume that you mean that an infinitely-large Universe can't become smaller if all of space is shrinking at a finite rate at a given time.

Depends on what you mean by 'smaller'. If you shrink the universe by half, then the density octuples, so it has by that measure an eighth the volume for any given set of matter. But an infinite universe has by definition no meaningful size. There is no number that represents its size or volume, and thus no different number representing the size after the shrinking. This is what Kryptid means by 'cannot become smaller'. There is no size number to change.

[Dave Lev (OP)]

They don't say how they measure distance in that graph. There are many ways to do so, and they're approximately the same only for nearby objects. That graph goes only to about 2 billion light years away, so yea, it doesn't matter much. But we see galaxies much further away than that, and distances become meaningless without specification of coordinate system used.  My example object is GN-z11, a very distant galaxy. Some typical choices:

1) Inertial coordinates: Only in inertial coordinates is light speed a constant c, and the coordinate system only applies to space that is more or less Minkowskian (flat), which is not true at large scales. In such coordinates, light can get from anywhere to anywhere else given enough time. There are no event horizons. The Milne solution uses such coordinates. Using such coordinates, the current size of the entire universe (relative to the inertial frame of Earth) is a sphere of radius about 13.8 BLY. Distances are measured along lines of simultaneity in the chosen frame. GN-z11 is about 13.5 BLY away, and the light we see now was emitted 6.7 BY ago.

2) Proper distance, comoving coordinates: This is the only coordinate system where H0 is meaningful. There is no maximum speed for anything, so there is no problem with objects at arbitrarily large separations after finite time. Distances are proper distance (measured by adjacent comoving rulers at a given time) traced on lines of constant cosmological time.
GN-z11 is a proper distance of about 31 BLY away and the light we see now was emitted 13.2 BY ago from only about 2 BLY away. Light from sufficiently distant events will not reach us due to acceleration of expansion forming event horizons.

3) Comoving distance/coordinates: In these coordinates, light speed is a function of time (c/scalefactor). Most objects (galaxies) are reasonably stationary and their distance is fixed since the big bang. Distances are proper distance (measured by adjacent comoving rulers at the current time) traced on a line of 13.8 BY cosmological age.
GN-z11 is a proper distance of about 31 BLY away and the light we see now was emitted 13.2 BY ago from a comoving distance of about 31 BLY.  Light from sufficiently distant events will not reach us due to dark energy slowing light speed to the extent that it can never reach us.

4) There is also the dubious light-travel distance, which isn't a valid coordinate system at all, but declares the distance to objects to be c/t from emission event. Light from GN-z11 was emitted from about 13.2 BLY away as measured by light travel time.

Dear Halc
Thanks for your deep explanation about:
1. Inertial coordinates
2. Proper distance, comoving coordinates
3. Comoving distance/coordinates
4. the dubious light-travel distance.
I have already read it and I do appreciate your explanation.
The Proper distance, comoving coordinates & Comoving distance/coordinates are key elements in the BBT theory.
However, I hope that you confirm that we do not monitor or measure the coordinates in space as we can't technically monitor the space itself.
We can just monitor the ordinary matter in space - as that very distant galaxy (like GN-z11) in your example.
https://en.wikipedia.org/wiki/GN-z11
1. Redshift   11.09
2. Helio radial velocity = 295,050 ± 119,917 km/s (which is almost the speed of light).
3. Distance ≈ 32 billion ly (9.8 billion pc)  (present proper distance) ≈13.4 billion ly (4.1 billion pc) (light-travel distance)

Do you agree that the understanding about the light-travel distance is fully based on the BBT concept that the space itself is expanding?
However, as we can only measure the galaxies and not the space itself, did you ever consider a possibility that there is no expansion in space and we just observe the expansion of the galaxy in a fixed space?
In this example we clearly measure a distance of  32 billion ly. (we call it - present proper distance)
However, that measurement breaks the fundamental understanding of the BBT that the age of the universe is just 13.8BY.
Therefore, it is vital to "normalize" that measured distance to the total age of the Universe as stated by the BBT.
In order to do so, it is stated that the light travel distance is 13.4 billion ly while we measured that the present proper distance (real distance?) is 32 billion ly.
Hence, could it be that the idea about proper/comoving close the gap between the real measurements to the requested parameters of the BBT?

Quote from: Dave Lev on Today at 06:07:46
Is there any possibility for us to look again on all the current observations/measurements without the BBT glass/filter?

You can, but so far the Big Bang theory is still the best candidate for explaining the observations.

So why do you kill any other candidate that could offer better  explaining for the observations?
Why you are flexible for all the BBT problems, but show almost zero flexibility to the others?

Do you agree that if one day we would discover that the real age of the Universe is 100Bly instead of just 13.8 BY, then technically we could fully accept the idea that the real the measurements of 32 BLY fully represents the light-travel distance to that galaxy?

Quote from: Dave Lev on Today at 06:07:46
So, why can't we just release the cosmic time?

What do you mean by "releasing" cosmic time?

https://en.wikipedia.org/wiki/Cosmic_time
"Cosmic time, or cosmological time, is the time coordinate commonly used in the Big Bang models of physical cosmology.
Such time coordinate may be defined for a homogeneous, expanding universe so that the universe has the same density everywhere at each moment in time"
"The current physical cosmology estimates the present age as 13.8 billion years."

As the BBT can only explain the observable universe size, while we do understand that the real universe should be significantly bigger than the observable universe - why can't we look again on the measurements without the BBT filtering?

Are you ready to give longer age to the entire Universe? So would you consider a possibility that the BBT took place much longer time ago?
What about  Bogie_smiles theory with regards to infinite bangs?

If you shrink the universe by half, then the density octuples, so it has by that measure an eighth the volume for any given set of matter.

Would you kindly accept (for just one moment) the idea that the expansion is just in the galaxies while the space itself is fixed and there is no shrink in the universe space?

[Halc]

The Proper distance, comoving coordinates & Comoving distance/coordinates are key elements in the BBT theory.

Coordinate systems (CS) are abstract tools, hardly key elements since any physical system can be expressed to a point using any coordinate system you want. But if you say some object is 10 BLY away, that's a fairly meaningless statement without identification of the coordinate system used to express that distance.

GN-z11
1. Redshift   11.09

A CS independent empirical measurement.

2. Helio radial velocity = 295,050 ± 119,917 km/s (which is almost the speed of light).

The 295050 seems to be the inertial velocity that would yield that redshift. The ±119917 is baffling in that context. That's 40% in either direction, which seems to make no sense. Typo in wiki?

3. Distance ≈ 32 billion ly (9.8 billion pc)  (present proper distance)

Now they switch to CS 2 or 3. If it is 10000 mpc away, per Hubble's law it should be receding at 700,000 km/sec which is about 2.3c, hardly the speed reported just above. But that speed was reported using CS 1, not CS 2. All very inconsistent of the wiki writers. Yes, in cosmological coordinates, it is receding at over 2c and is about 32 GLY away. It, like everything else, is currently accelerating, which is not true using CS 1 (inertial) where GN-z11 is currently still decelerating.

≈13.4 billion ly (4.1 billion pc) (light-travel distance)

Method 4, which is not a CS at all.

Do you agree that the understanding about the light-travel distance is fully based on the BBT concept that the space itself is expanding?

Light travel distance is based on pop articles aimed at people who don't understand the mathematics. No, it doesn't leverage the concept of space expansion at all. No clock would measure that time. No tape measure would measure that distance. I mean, if it traveled over 13 BLY to get here, it must have been emitted from 13.4 BLY away, and got there in only 400 MY, which is over 33c. Are they suggesting GN-z11 was initially moving at over 33c? And redshift of only 11??  Method 4 values are self contradictory, and as I said, only used in pop articles.

However, as we can only measure the galaxies and not the space itself ...
In this example we clearly measure a distance of  32 billion ly. (we call it - present proper distance)

Ooh, you just said we don't measure space, but then assert that we clearly measured the space of 32 BLY. Contradicting yourself I see. Stop asserting things that are 'clearly' when you have no idea what you're talking about. Almost every time you use the word 'clearly', you're asserting something you know to be wrong.
When you use the word 'vital', it means you know you're talking about something that doesn't matter.

However, that measurement breaks the fundamental understanding of the BBT that the age of the universe is just 13.8BY.

There was no mention of age in that distance measurement, so another nonsense assertion.

Therefore, it is vital to "normalize" that measured distance to the total age of the Universe as stated by the BBT. In order to do so, it is stated that the light travel distance is 13.4 billion ly while we measured that the present proper distance (real distance?) is 32 billion ly.

13.4 is nonsense. 32 is relative to cosmological coordinates. Distances are CS dependent, so none of them is more real than any other (except for that light-travel one which is definitely less real).

Hence, could it be that the idea about proper/comoving close the gap between the real measurements to the requested parameters of the BBT?

That's a word salad. No idea what 'parameters' you're referencing here. I don't think you know either.

Is there any possibility for us to look again on all the current observations/measurements without the BBT glass/filter?

Yea. You get redshift of 11 and not much more. Certainly no parallax. You need a model to get a distance from that.

So why do you kill any other candidate that could offer better  explaining for the observations?

We don't, but no candidate does better, and there have been a lot of them. But it doesn't take a rocket scientist (pun intended) to see that the motion of everything we see puts it all right here about 14 BY ago, not earlier or later, but all at once.

Do you agree that if one day we would discover that the real age of the Universe is 100Bly instead of just 13.8 BY

But using CS 1 (but a different inertial frame than that of Earth), it IS 100 BY old (BLY is a distance, not an age).So you can make it any age you want with correct choice of frame/observer.

So, why can't we just release the cosmic time?

You didn't explain what you meant by 'release', but in CS 2 and 3 (cosmological coordinates), time is measured by what is occasionally called 'cosmic time'. It's the time since all the stuff was right here.

What about  Bogie_smiles theory with regards to infinite bangs?

B_S suggests explosions of new material periodically occurring at random locations in existing space which would just form a black hole and not result in any matter at all. If anyone was actually capable of producing a new viable theory, they'd not be wasting their time posting it on a forum.

Would you kindly accept (for just one moment) the idea that the expansion is just in the galaxies while the space itself is fixed and there is no shrink in the universe space?

The galaxies are not themselves expanding. If they did, the space between them would be shrinking then, not growing. We'd see no redshift if there was no recession.
If you mean static space with galaxies moving through it away from each other, that's the first CS. It is known as the Milne solution to the FLRW equations, and only works with a zero-energy universe. Such a universe would currently be 13.8 BLY in radius, a ball with an abrupt edge, and it would look the same (isotropic) from any view point.

[Bored chemist]

So what is the real size of the entire Universe?

Why did you put the word "so" in there?

I realise it's a short question, but it's important.
Why did you put that word in your answer?

[Kryptid]

So why do you kill any other candidate that could offer better  explaining for the observations?

We don't yet know of any.

As the BBT can only explain the observable universe size, while we do understand that the real universe should be significantly bigger than the observable universe - why can't we look again on the measurements without the BBT filtering?

There's no reason you can't, but like I said, those very measurements support the BBT.

Are you ready to give longer age to the entire Universe?

If we find evidence that supports that, yes.

So would you consider a possibility that the BBT took place much longer time ago?

If we find the evidence for that, yes.

What about  Bogie_smiles theory with regards to infinite bangs?

I don't think there's evidence for it.

Why you are flexible for all the BBT problems, but show almost zero flexibility to the others?

Because the BBT has the best overall explanation so far.

Do you agree that if one day we would discover that the real age of the Universe is 100Bly instead of just 13.8 BY, then technically we could fully accept the idea that the real the measurements of 32 BLY fully represents the light-travel distance to that galaxy?

That would depend on the specifics.

Would you kindly accept (for just one moment) the idea that the expansion is just in the galaxies while the space itself is fixed and there is no shrink in the universe space?

The galaxies themselves don't expand, so that wouldn't make any sense.

[Dave Lev (OP)]

Quote
Is there any possibility for us to look again on all the current observations/measurements without the BBT glass/filter?

Yea. You get redshift of 11 and not much more. Certainly no parallax. You need a model to get a distance from that.

This is the most important parameter in our discussion.
Redshift is all about velocity and ONLY about velocity.
Converting from redshift z to velocity v measured in km/sec is easy - the formula is v = c z.

https://en.wikipedia.org/wiki/Hubble%27s_law#/media/File:Velocity-redshift.JPG
A variety of possible recessional velocity vs. redshift functions including the simple linear relation v = cz;

We should focus only on linear relation.
Therefore, when we observe a galaxy with redshift of 1 it means that this galaxy is moving away from us at c.
The redshift of galaxy GN-z11 is about 11. Therefore, this galaxy is moving away from us at 11c.
Redshift can't give us any indication about the distance.
In general we can assume that the faster it moves the further it is located.
Hubble verified that there is some sort of correlation between the distance to redshift
However, there might be two galaxies with exactly the same redshift while their distance to us might be totally different.
Hence, redshift is all about velociy and it is a severe mistake to extract the distance from the redshift.
We should ignore the cosmologic redshift and accept the redshift as is.
Velocity and only velocity.
Based on that understanding we can't know the exact distance to that GN-z11 galaxy, however, it is still in a distance that we can observe.
If one day we would improve our tools, we might see other galaxys that are located further away (with higher or lower redshift).
Theoretically, there should be unlimited no of galaxies around us and the further we go it is expected that their redshift would be higher.
The Cosmic Microwave Background is a reflection of radiation from all the galaxies around us.
We had been informed that the CMBR redshift is 1100, but I would expect that there should be wide spectrum of redshift in this CMB as it comes from all the galaxies around us up to the infinity.
We can't extract the distance from that redshift.
Just understand that the meaning of redshift 1100 is that those galaxies are moving away from us at 1100c.

Quote from: Dave Lev on 20/05/2022 19:37:42
Are you ready to give longer age to the entire Universe?

If we find evidence that supports that, yes.

Yes we have the redshift.
That redshift tells us the velocity of each galaxy.
It is not realistic to assume that galaxies that are moving away from us at 1100c (or higher) had been created just 13.8 By ago.

[Bored chemist]

The Cosmic Microwave Background is a reflection of radiation from all the galaxies around us.

No it isn't.
We know that because it has completely the wrong spectrum.
We can se galaxies. Andromeda is visible to the naked eye in good conditions which tells us that it emits visiblelight.
The microwave background does not include any visible light.
So we know you are wrong again.

[Halc]

Redshift is all about velocity and ONLY about velocity.

Quite wrong. It is coordinate system dependent (as your wiki graph shows), and I can have say a ship approach Earth at say 0.8c and show zero red or blue shift all the way. Lack of redshift doesn't imply zero velocity. Presence of redshift doesn't imply nonzero velocity.

Converting from redshift z to velocity v measured in km/sec is easy - the formula is v = c z.

No valid coordinate system yields that figure, so this too is entirely wrong. It's just a cheap Newtonian approximation for slow moving thing that shows only Doppler effect and no relativistic effects at all.

We should focus only on linear relation.

Why just the wrong one?

Redshift can't give us any indication about the distance.

Unless you utilize the BBT.

In general we can assume that the faster it moves the further it is located.

Not unless you assume BBT. Without that, you're back to square 1.

Hubble verified that there is some sort of correlation between the distance to redshift

Yea, and it wasn't v=cz, a relation that had been discredited over half a century before the recession findings.

Hence, redshift is all about velociy and it is a severe mistake to extract the distance from the redshift.

Do you have empirical evidence (like Hubble does) that such a relation is wrong? You don't. So it's you making the severe mistake of ignoring empirical measurements. This is straight denial of evidence Dave. A new theory might better explain evidence, but if you need to deny the evidence itself, it turns into religion, not science. Again, don't make me lock the topic.

Based on that understanding we can't know the exact distance to that GN-z11 galaxy, however, it is still in a distance that we can observe.

They know it's distance pretty accurately. The error bars are not large.

If one day we would improve our tools, we might see other galaxys that are located further away (with higher or lower redshift).

Only a little further, beyond which galaxies have not yet formed enough to, well, be galaxies. Any more distant galaxy has to be well on this side of the CMB barrier since the 'dark ages' (at least 300M years worth) lie between.

It is not realistic to assume that galaxies that are moving away from us at 1100c (or higher) had been created just 13.8 By ago.

No. If it was moving that fast, it would have been here about 43 million years ago, so according to that bit of nonsense, the universe is only 43 billion years old when those most distant galaxies where here.
Cosmological coordinates very much supports a recession speed of 1100c. A galaxy currently ~15 trillion LY away would be receding about that fast. That's trivially calculated by Hubble's law. We'd not be able to see light from it since it is well outside the visible universe. No light that we see today has ever been further away than a proper distance of about 6 BLY away, or 7 BLY if you use inertial coordinates.

[Dave Lev (OP)]

Dear Halc
As long as we monitor the observation by the BBT filtering, we only get "evidences" that meet the BBT requirements.
Therefore, there is no room for better explanation based on those BBT filtered "evidences".
I have got the impression that you are ready to give me the possibility to eliminate the BBT filtering (including the idea of space expansion):

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Is there any possibility for us to look again on all the current observations/measurements without the BBT glass/filter?

Yea. You get redshift of 11 and not much more.

Quote from: Dave Lev on 20/05/2022 19:37:42
As the BBT can only explain the observable universe size, while we do understand that the real universe should be significantly bigger than the observable universe - why can't we look again on the measurements without the BBT filtering?

There's no reason you can't, but like I said, those very measurements support the BBT.

So, are you ready to give me the possibility to eliminate that BBT filtering?

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Converting from redshift z to velocity v measured in km/sec is easy - the formula is v = c z.

No valid coordinate system yields that figure, so this too is entirely wrong.

Unless we ignore the idea of space expansion and offer better theory that can explain that kind of figure.

It's just a cheap Newtonian approximation for slow moving thing that shows only Doppler effect and no relativistic effects at all.

Would you kindly give me the possibility to focus on Newtonian also for high velocity.

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Hence, redshift is all about velocity and it is a severe mistake to extract the distance from the redshift.

Do you have empirical evidence (like Hubble does) that such a relation is wrong? You don't. So it's you making the severe mistake of ignoring empirical measurements.

Hubble had found that as we go further away it is expected to find galaxies with higher redshit, Never the less, its empirical measurements aren't fully linear.
We can see it in the following diagram:
https://en.wikipedia.org/wiki/Hubble%27s_law#/media/File:Hubble_constant.JPG
We can discuss about it.
However, I would like to verify your permission to eliminate the BBT filtering including the idea of space expansion and let me use that cheap Newtonian formula also for high velocity.
If there is no permission, then I would stop the discussion about the redshift.

[Dave Lev (OP)]

The microwave background does not include any visible light.
So we know you are wrong again.

Those galaxies with high redshift are located too far away from us to get their visible light.
Therefore, the CMBR is all about energy heat radiation.
However, as we move further away, the heat energy is decreasing by R^2 while the total galaxies no is increasing by R^3.
Therefore, we can get the CMBR heat energy from up to redshift of about 1100. Above it the heat energy is totally neglected.
Therefore, the total temp of CMBR is just 2.7K
However, if we had the technology for to detect further away heat energy, we could technically detect CMBR  with redshift of above 1100.
Therefore, as long as we keep the BBT filtering, you would consider that I'm wrong.



Please look carefully on this diagram.

https://en.wikipedia.org/wiki/Hubble%27s_law#/media/File:Hubble_constant.JPG

If we would understand how it works, we would understand how the entire universe works.

No. If it was moving that fast, it would have been here about 43 million years ago, so according to that bit of nonsense, the universe is only 43 billion years old when those most distant galaxies where here.

Please be aware that we get the CMBR heat energy from up to 1100c galaxies.
However, as the universe has no limit, there are other galaxies at further location with higher redshift.
Theoretically if the universe is infinite and it is full with galaxies, then 43 B years is not good enough for the total age of the entire universe.

[Kryptid]

It is not realistic to assume that galaxies that are moving away from us at 1100c (or higher) had been created just 13.8 By ago.

Why not?

So, are you ready to give me the possibility to eliminate that BBT filtering?

When a better theory comes along, yes.

Would you kindly give me the possibility to focus on Newtonian also for high velocity.

Newton's equations don't give accurate answers at such high velocities. You need relativistic ones for that.

[Dave Lev (OP)]

Quote from: Dave Lev on Today at 04:07:37
So, are you ready to give me the possibility to eliminate that BBT filtering?

When a better theory comes along, yes.

Thanks
Do appreciate!
So, would you kindly let me eliminate also the idea of space expansion?

Quote from: Dave Lev on Today at 04:07:37
Would you kindly give me the possibility to focus on Newtonian also for high velocity.

Newton's equations don't give accurate answers at such high velocities. You need relativistic ones for that.

Please let me use Newtonian also for high velocity.
Once you give me the permission, I would explain how the entire universe really works.
But please don't kill my message in the first bumper.

[Kryptid]

So, would you kindly let me eliminate also the idea of space expansion?

If a better explanation for galactic recession is ever discovered, yes.

Please let me use Newtonian also for high velocity.

Well, you can, but it'll be wrong.

Once you give me the permission, I would explain how the entire universe really works.

As long as it's not Theory D.