Genady

To discuss these questions, we need to establish what is meant by 'geometry.'

This is more like it. Acceleration is a separate effect, though. Do you see that this dependence of expansion rate on distance is the same for all galaxies and thus means homogeneity?

No, I do not mean anything like this.

Oh yes, it is compatible! It is "expansion 101." Now, with this comment, you show that you don't know the very basics of the topic you try to argue about. I am happy to explain complications, but basics, you should learn yourself. If you really want to know, that is. Anyway, you made it clear with this last comment, that I have nothing more to do in this conversation. Come back, when you understand that Hubble Law means homogeneity and isotropy. Until then, I am out.

Who are the "we" that you refer to? No, the space does not get bigger. The statement of "making the same space bigger" does not have any meaning. Space does not have "size", to start with. Also, space does not have identity to be "the same" or not. Expansion of the universe makes the distances between neighboring free-falling systems larger. Neighboring in real universe means at the distances of the order of magnitude about 100 Mpc.

Exactly. During the expansion of the universe, no "new space" is added to it. What happens is, the geometry of the space changes.

I'd be glad to try, but I don't know what. Maybe you can clarify your request.

Space is not an entity. There is no "new space" or "old space."

I've received this "riddle" from a friend this morning: Doing my best to translate it to English here, while cutting off irrelevant details. Bob got an electronic clock in shape of an apple. It shows time with a precision of a hundredth of a second. As he was moving down on an escalator, Bob threw the clock up and noticed that at the top of its trajectory the clock showed 11:32:45:81. His teacher Mary was moving up on the escalator at the same time, and she noticed that the clock showed 11:32:45:74 at the top of its trajectory. Find the speed of the escalators, given that they move with the same speed, at the angle of 300 to horizon. Ignore the air friction. Take g = 10 m/s2.

I've already answered such question here: https://www.scienceforums.net/topic/132162-is-the-universe-at-least-136-billion-years-old-is-the-universe-not-expanding-at-all-did-the-universe-begin-its-expansion-when-hubble-measured-its-redshift-for-the-first-time-or-was-light-twice-as-fast-135-billion-years-ago-than-it-is-today/?do=findComment&comment=1246785 Here it is again:

It's the distance that the light covered since it was emitted until it has reached us. The light-travel distance. If the light had an odometer attached, that would be what its odometer shows.

The galaxy is now at about 34 billion light years from us. Its redshift z=11. Thus, when the light was emitted, it was at the distance 34/12=2.8 billion light years away.

It was not in that position 13.5 billion years ago. The surface of last scattering was in that position 13.8 billion years ago. The surface of last scattering has z=1100. The galaxy has z=11.

It is homogenous and isotropic on the scale of >100 Mpc (>300 million light years). And on cosmological distance concepts, esp. the proper distance and the light-travel distance.

This clearly confirms that YOUR concept is mistaken, and you keep piling wrong conclusions on top of each other. The cosmological concept, OTOH, is very clear and consistent, but it needs careful study and math to be applied correctly.

No, your calculations are incorrect. We do. See e.g. List of the most distant astronomical objects - Wikipedia: You see, 33.6 billion light-years!

We see the source of the cosmic microwave background. This source is now 46 billion light years away.

Your numbers are off. The radius of the visible universe is about 46 billion light years, not 13.5 billion light years. See the very first comment above. The galaxy did not emit light when the universe was only 40 million light years large. The cosmic microwave background light was emitted then. As I've explained in my previous post, this tiny dot looks not "much", but 12.6 times bigger. It was not "much", but 12.6 times closer.

The farthest galaxy observed today has a redshift of 11.6. This means that when the light was emitted it was 12.6 times closer to us than it is now. This means that the image of the galaxy that we see is 12.6 times larger than it should be for its current distance. A tiny dot enlarged 12.6 times is still a tiny dot.

For each galaxy we measure its redshift, z. The light we see now left the galaxy, which is at the distance d from us now, when it was at the distance d/(z+1) from us.

No. If the light had an odometer attached to it, the odometer would show that it has covered the total distance of 13.5 billion light years.

Million. As it was moving toward us with the speed of light, the distance in front of it that it still had to cover, kept growing.

The light of the cosmic microwave background was emitted from about 40 mln ly away.

I can imagine it to be so if there is little text and the video contains mostly visual and auditory images. These videos don't need to be converted. Let's limit my request to videos that try to convey a textual information / message.