2 minutes ago, Genady said:

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

Please explain.

6 minutes ago, tmdarkmatter said:

I can see that with the expansion, we are just creating new space out of nowhere and we are parking our extra light from these old galaxies there, so it needs more time to reach us. So, actually we suppose that this universe is going to be converted into a lightverse (space only filled with light) without any visible galaxies and that all these galaxies are going to disperse completely unevenly (soccer field with pinhead in the center) until they all desintegrate. During the "big bang", matter was created out of nowhere, so why can we not create "space" out of nowhere too? What if we are wrong with all the redshift theory? Isn´t it much more logical that the universe is not expanding at all, instead of the need to create space and matter out of nowhere? What if gravity is responsible for red shifting instead and bing bang never happened? Did you ever question all these ideas? Isn´t it highly suspicious that we are existing exactly in a perfect time to see a sky full of galaxies? Why do we not exist a couple of billions of years later when most of these galaxies are gone, or a couple of billions of years earlier, when the density of the galaxies would be extremely high so we could not sleep at night. I am wondering what kind of sky the first cyanobacteria on earth had above them. Was it a sky full of galaxies or was it the same then today? Also, the entire universe should be slowly cooling down due to this expansion, so the galaxies we see far away should actually be much hotter than ours.

Anway, of course this is what we have so far. I am just trying to challenge you. There is no need to define me as a troll. I can also accept everything that is beeing offered to me since I was born and never question anything. I can repeat everything like a parrot too. But if we all think alike, no one is actually thinking.

This now reads like a "Gish gallop". You seem to have run up the Jolly Roger and to be throwing as many wrong ideas out at once as you can, perhaps with the object of defeating attempts to correct you. What's all this about galaxies disintegrating? Who says matter was "created out of nowhere"? Have you read the evidence for the expansion of the universe? How would you account for that evidence if there were no expansion?  

As for why do we, the human race, exist when cosmological conditions are, er, favourable for us to exist, that is a bit of a silly question, surely? 

At the moment you remind me more of a seagull than a parrot. Do you want to slow down, take things one at a time and have a discussion we can all learn from? Or are you anxious to move on quickly to some crank agenda of your own, hence all this rubbish in your latest post?  

2 minutes ago, tmdarkmatter said:

Please explain.

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

19 minutes ago, tmdarkmatter said:

Please explain.

I think what @Genady means is space is not some "stuff" of which you can put in more of it. I agree with pretty much everything else he --and others-- have said here. 

You can't use naive addition of velocities to "cancel out" receding speed of galaxies with speed of light. Both have dimensions of length / time, but are very different things. One is an expansion parameter that applies to the whole of the universe as per cosmological standard model; the other is the speed of photons when they go "past your nose" so to speak. The latter is always c (a universal constant.) For photons reaching you from near the cosmic horizon, what you get is extreme Doppler shift, so they are lower and lower frequency (longer and longer wavelenght) the closer you get to this horizon. This horizon is of a kinematical nature, but it doesn't manifest itself as stopping the photons in their tracks, but as making them closer and closer to invisible.

The other mistake that you're making --ignoring space expansion since those photons were emitted-- I also agree with. The fact that it's a mistake, that is.

10 minutes ago, joigus said:

space is not some "stuff" of which you can put in more of it

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

2 hours ago, exchemist said:

2 hours ago, tmdarkmatter said:

If this model works, I think you should be able to tell me where this galaxy was 13.5 billion years ago, where the light was emitted, where the galaxy is now and how fast this light travelled what distance to reach us to see if it makes sense. And why we are seeing tiny dots instead of clusters like the neighboring clusters of our milky way.

But how is it possible that this light travels for 13.5 billion years if the galaxy was only 2.8 billion light years away?

Because of the stretching while it was en route, presumably. 

Hi Joigus, long time no see!

But if we stick to the idea that we are point A and the galaxy we see 13.5 billion years away is point B and the light coming from this point B travelled for 13.5 billion years only to travel 2.8 billion light years, how can you explain that if not combing both movements, the movement of photons and the movement of expansion? Why do we need to separate both movements when the photon travelling remains the same under influence of both movements?

I also think that we still need a better definition of space. If space expands, shouldnt its characteristics change with time? Can a certain amount of space at the beginning of the universe contain the same amount of atoms than space billions of year later, or is there a difference?  Will space always allow for the same movements of particles passing through it or will particles need more/less energy to cross this space in the future? Will the speed of light through this expanding space always remain the same? Will the effect of gravity through this space always remain the same? Will time allways pass by the same in this space? I think we should still investigate all this.

On the other hand, I wanted somebody to tell me if the light coming from a galaxy far away would not need much more time to travel through the first lightyear of space (effective distance) then to travel through the last lightyear (effective distance) before reaching us, because the effect of expansion on these photons is much higher at the beginning of their journey, because the distance to point A is much longer and therefore there is more expansion of the space in between. Of course this is if we are allowed to combine the movement of photons with the movement of expansion in a common space.

I also still do not understand why the image of the light coming from this galaxy far away would not be more similar to a galaxy at a distance of 2.8 billion light years or even closer, because this light never was 13.5 billion light years away from us. But I think Genady already said that the galaxy looks much bigger than it should be.

17 minutes ago, Genady said:

What happens is, the geometry of the space changes.

What does that mean? We just make the same space bigger?

1 minute ago, tmdarkmatter said:

Hi Joigus, long time no see!

But if we stick to the idea that we are point A and the galaxy we see 13.5 billion years away is point B and the light coming from this point B travelled for 13.5 billion years only to travel 2.8 billion light years, how can you explain that if not combing both movements, the movement of photons and the movement of expansion? Why do we need to separate both movements when the photon travelling remains the same under influence of both movements?

I also think that we still need a better definition of space. If space expands, shouldnt its characteristics change with time? Can a certain amount of space at the beginning of the universe contain the same amount of atoms than space billions of year later, or is there a difference?  Will space always allow for the same movements of particles passing through it or will particles need more/less energy to cross this space in the future? Will the speed of light through this expanding space always remain the same? Will the effect of gravity through this space always remain the same? Will time allways pass by the same in this space? I think we should still investigate all this.

On the other hand, I wanted somebody to tell me if the light coming from a galaxy far away would not need much more time to travel through the first lightyear of space (effective distance) then to travel through the last lightyear (effective distance) before reaching us, because the effect of expansion on these photons is much higher at the beginning of their journey, because the distance to point A is much longer and therefore there is more expansion of the space in between. Of course this is if we are allowed to combine the movement of photons with the movement of expansion in a common space.

I also still do not understand why the image of the light coming from this galaxy far away would not be more similar to a galaxy at a distance of 2.8 billion light years or even closer, because this light never was 13.5 billion light years away from us. But I think Genady already said that the galaxy looks much bigger than it should be.

What does that mean? We just make the same space bigger?

Now you are throwing out even more nonsensical questions. If you read any article on the Big Bang theory it will explain that the early universe was denser, i.e. more matter in a more confined space, than today. So what's all this about whether it can hold the same number of atoms?

You don't need "energy" to "cross space". Space does not inhibit particles from passing through it.  You are suddenly writing as though you have no grasp of any physics at all.  

It's absurd of you to reel off a list of dumb questions and airily state that we should "investigate all this". Ballocks! All we should do is get you to sit down and learn some damned physics. 

2 minutes ago, tmdarkmatter said:

We just make the same space bigger?

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. 

8 hours ago, Genady said:

It is homogenous and isotropic on the scale of >100 Mpc (>300 million light years).

Also, this is not compatible with a universe where the acceleration depends on the distance away from us. If galaxies 13.5 billion light years away move away from us almost at the speed of light and galaxies next to us almost do not move away from us in the same time frame, this is not possible.

4 minutes ago, Genady said:

Space does not have "size", to start with. Also, space does not have identity to be "the same" or not

Do you mean that space cannot be measured?

2 minutes ago, tmdarkmatter said:

Also, this is not compatible with a universe where the acceleration depends on the distance away from us. If galaxies 13.5 billion light years away move away from us almost at the speed of light and galaxies next to us almost do not move away from us in the same time frame, this is not possible.

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.

10 minutes ago, exchemist said:

Now you are throwing out even more nonsensical questions.

Ok, so it is wrong to even ask these questions about space.

11 minutes ago, Genady said:

I am happy to explain complications, but basics, you should learn yourself. If you really want to know, that is.

So you mean that galaxies all move away from us at the same speed and that from our perspective we see the ones further away moving away faster only because the light needs more time to reach us?

29 minutes ago, tmdarkmatter said:

So you mean that galaxies all move away from us at the same speed and that from our perspective we see the ones further away moving away faster only because the light needs more time to reach us?

No, I do not mean anything like this.

6 minutes ago, Genady said:

So you mean that galaxies all move away from us at the same speed and that from our perspective we see the ones further away moving away faster only because the light needs more time to reach us

But you mean that the space between each pair of galaxies should expand at the same speed and therefore those that are far away move away faster because there are more of these "distances between galaxies" and this speed is even increasing (acceleration).

So you suppose that the "network of galaxies" is perfect and homogeneously expaning?

Of course, all this should apply if the universe is infinite.

3 minutes ago, tmdarkmatter said:

But you mean that the space between each pair of galaxies should expand at the same speed and therefore those that are far away move away faster because there are more of these "distances between galaxies" and this speed is even increasing (acceleration).

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? 

2 hours ago, Genady said:

What happens is, the geometry of the space changes.

As the geometry changes does the geometry of an atom change?

Assuming we measured hydrogen geometry 7 billion years ago is it similar to today's hydrogen geometry?

Are atoms part of space?

2 hours ago, Genady said:

Space does not have "size", to start with. Also, space does not have identity to be "the same" or not.

What is that that doesn't have identity or size?...I thought when you are referring to size their is aspects of dimensions and when their is dimensions there is geometry.

29 minutes ago, MJ kihara said:

As the geometry changes does the geometry of an atom change?

Assuming we measured hydrogen geometry 7 billion years ago is it similar to today's hydrogen geometry?

Are atoms part of space?

What is that that doesn't have identity or size?...I thought when you are referring to size their is aspects of dimensions and when their is dimensions there is geometry.

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

 

4 hours ago, tmdarkmatter said:

I also still do not understand why the image of the light coming from this galaxy far away would not be more similar to a galaxy at a distance of 2.8 billion light years or even closer, because this light never was 13.5 billion light years away from us

Quantum of light is photon...the object in the image is perceived as of when that object emitted, reflected e.t.c those photons..you see the sun as when those photons in sunlight were emitted roughly 8 minutes ago therefore,if you see  a galaxy that is 7 billion years older it mean the photons your detecting were emitted or came from the galaxy 7 billion years ago...in those 7 billion years where you are present( the position in the universe) in our galaxy was much closer to that galaxy position.As the photons were moving from that galaxy to your present position the space was expanding and since the speed of light(photon) is constant,therefore,it had to cover a larger distance to reach your present position,to cover or move a certain distance it's work done,therefore,those photons became less energetic i.e red shifted..at the same time the space within the photons wavelength is expanding,therefore,also contributing to red shift phenomenon.

If the universe was static those photon could have passed your position long time ago...meaning perceiving the past could have been much difficult,since we can't be able to chase after the light 'nothing moves faster than speed of light'.

8 hours ago, Genady said:

Do you see that this dependence of expansion rate on distance is the same for all galaxies and thus means homogeneity? 

Yes, I understand what you mean. But instead of increasing the distance between the galaxies, we can also say that all the galaxies are just shrinking and the result would be the same. This would mean that all atoms and even photons are shrinking. If space cannot be defined as an identity or size, there is no real reference for us to compare our sizes with, so the measuring tape we are using to measure objects on earth would also be shrinking and therefore we would not even realize that we are indeed shrinking. Maybe the size of the universe is always the same and it just began with a lot of huge galaxies with enormous atoms that have been shrinking since the beginning. This would be the "shrinkverse" lol. If we could observe the universe from outside (with other benchmarks) and it would not change its size, then the "shrinkverse" would definitely be a reality.

It is also strange that there is absolutely no expansion within galaxies because of the effect of gravity holding the galaxies together. It seems artificial that there should be absolute borders between regions with expansion and regions without. Will gravity (a weak force) really be strong enough to hold all kind of objects together, even some highly scattered huge nebulae?

On the other hand it is also quite strange that the expansion of the universe is completely homogeneous. Why would that be the case? It seems completely unnatural, because it would be the only force or effect in the universe that is absolutely homogeneous.

I think there are two ways to absolutely confirm that the universe is expanding.

1. If we can really confirm that galaxies are getting smaller because they are moving away from us. In order to do this, we would need to observe the same galaxy for millions of years.

2. If, from the 200 billion galaxies we found so far, there is at least one of them becoming invisible because it is crossing the visible horizon so we can no longer see it. That would also be a perfect proof that galaxies are moving away.

Until we get this confirmation, we will just keep holding on to red shift as the only "proof" of expansion, but considering that gravity can also be the cause of red shift, I think that this "proof" alone is insufficient. But this is only my opinion.

The only thing we would need to find is a mechanism of why light coming from the furthest galaxies has to leave a bigger gravitational well than light coming from closer galaxies and suddenly the universe never expanded. Therefore, I wish we would have one of the methods mentioned above to actually confirm the expansion.

11 hours ago, tmdarkmatter said:

Ok, so it is wrong to even ask these questions about space.

 

Don't be a jerk. That is not what I said at all.

What is irritating and unacceptable is for you to ask a raft of questions that are stupid , AND then insist that "we" investigate them, as if they are in some way profound or unanswered as yet.

The questions you have started asking, in profusion, halfway through this thread, suggest a complete  lack of understanding of physics, totally inconsistent with the level at which you started the thread. You are screwing around with us. 

Edited August 9, 20232 yr by exchemist

3 hours ago, tmdarkmatter said:

But instead of increasing the distance between the galaxies, we can also say that all the galaxies are just shrinking and the result would be the same. This would mean that all atoms and even photons are shrinking.

No, you can’t just say it. You need a model, and have to look at the implications of the model to see if it’s consistent with what we observe. 

There are threads discussing shrinking matter conjectures, and why they don’t work.

such as https://www.scienceforums.net/topic/128216-on-the-observational-constrains-of-shrinking-matter-theories/

 

 

7 hours ago, exchemist said:

level at which you started the thread.

So I started the thread at a higher level. Interesting. I think science is not about me or how smart I am. I think it is about finding answers to questions. But if you think that space does not need a good definition or that we already know everything about space, ok, whatever. Then explain to me how this space expands and why.

And I must say that the article swansont posted here is quite interesting. Thank you.

And I have another question:

If Earth is moving at a speed of about 30 km/s around the sun, shouldn´t we see the milky way more red shifted when it is moving away from us compared to when it is moving towards us? If we can detect the effect of gravity in a little tower on the red shift of light, I think we should also be able to detect this difference every year.

And if we move at a speed of about 300 km/s around the center of the milky way, shouldn´t we see the galaxies behind us on this journey more red shifted than the galaxies in front of us? Unfortunately, it seems that we can still not confirm in what direction we are moving around the center of the milky way, but what if we are moving towards Andromeda and this galaxy therefore appears to be moving into our direction because it is more "blue shifted"?

By the way, you can give me a -1000 too, I really don´t care about this "reputation" or whatever that should be.

If asking the wrong questions means a lower reputation then something is wrong here. Bad reputation should be if I insult somebody or if I do not let others speak or if I post racist text or pornography. So this reputation is just that you do not like somebody showing up with different ideas or asking questions that "apparently were already answered".

So the lower my "reputation" gets while asking questions in a civilized manner, the lower the reputation of this website gets and the less credibility I have that people here are objective and open-minded.

I am really lucky for not beeing one of your children.

Edited August 10, 20232 yr by tmdarkmatter

This "reputation" seems to be only related to resentment the guys here have lol

How can asking questions reduce your reputation? This definitely does not make any sense, but it´s funny and shows me where human science stands today. This would have been totally different 30 years ago.

 

This page does not seem to be serious.

I came to this conclusion:

 

"If asking questions reduces the reputation, then this is the wrong place to ask questions."

"And if this is not a place to ask questions, then it is not a "scientific" forum at all."

3 hours ago, tmdarkmatter said:

How can asking questions reduce your reputation?

It doesn't.  Ignoring the answers can result in negative points.  Asking the same question over and over while ignoring the  answers that people took time to write will definitely give you negative points.  

Making up spur of the moment conjectures to answer your own question, because you don't like the answers you received is also an excellent way to get down votes.

Edited August 10, 20232 yr by Bufofrog

6 hours ago, tmdarkmatter said:

If asking the wrong questions means a lower reputation then something is wrong here. Bad reputation should be if I insult somebody or if I do not let others speak or if I post racist text or pornography.

Fallacious reasoning is your enemy here. It's insulting when someone bothers to explain something to you and then you reply using logical fallacies or some twisted version of what they said.

This, for example, is a classic strawman:

20 hours ago, tmdarkmatter said:

I think science is not about me or how smart I am. I think it is about finding answers to questions. But if you think that space does not need a good definition or that we already know everything about space, ok, whatever.

I found this extremely insulting. This got you 4 downvotes. It reminds me of the nationalist zealots who respond to any criticism of war with "If you think our troops don't need any support, ok, whatever". As a response, it seemed petulant and childish. Nobody suggested we already know everything about space.

And btw, science is NOT about finding answers to questions. It's about finding the explanations that have the most evidence to support them, so we can trust those explanations, and keep looking for better ones. If you think you've found the answer to a question, you stop looking, and we definitely don't want that.