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Bluemoon16
2016-Mar-30, 08:49 AM
Hello, I'm new here and have joined to help someone out. He has a theory which we like comments upon please. There are 19 points to this theory. Thank you in advance for your help, Bluemoon16.

1) Astrophysicists tell us that the light from quasars has taken 12.5 billion years to get here travelling at the speed of light. Correct?

2) Astrophysicists tell us that quasars are detected all around us at that distance, making the detected Universe 25 billion light-years across. Correct?

3) Astrophysicists say that because it has taken the light 12.5 years to get here we see quasars how they looked 12.5 billion years ago. Correct?

4) Astrophysicists tell us that at the time the light left those quasars they were travelling away from us at just under the speed of light. Correct?

5) That means that in the 12.5 billion years that it has taken that light (from 12.5 billion years ago) to reach us, the quasars will have moved away by another almost 12.5 billion light-years. Correct?

6) If they have moved by nearly another 12.5 billion light-years that means that they are actually nearly 25 billion light-years away from us. Correct?

7) Given that we see the light from where they were 12.5 billion years ago (the light from where they are now not having reached us yet, and won't reach us for another 25 billion years) we see them where they were 12.5 billion years ago, and not where they actually are now. Correct?

8) From that lot we can say that the quasars were actually 12.5 billion light-years away from us 12.5 billion years ago. Making the Universe at that time, 12.5 billion years ago, 25 billion light-years across. Correct?

9) If we go back in time by 2 billion years, to 14.5 billion years ago, those quasars travelling at almost the speed of light would have been roughly 2 billion light-years closer, at 10.5 billion light-years away. Correct?

10) That means that 14.5 billion years ago, when the Big Bang is supposed to have happened, the quasars were 10.5 billion light-years away from where we are now in all directions, making the Universe 21 billion light-years across at that time. Correct?

11) Astrophysicists tell us that immediately after the Big Bang there was inflationary period when the Universe went from the point entity of the Big Bang to the size of a melon. Correct?

12) Given 10 and 11 that is a melon 21 billion light-years across. Correct?

13) To get back to when the Universe would have been zero across, that is, the time when it was the point entity at the time of the Big Bang, we need to go back another 10.5 billion years before the point in statement 9. Correct?

14) 10.5 billion years before 14.5 billion years is 25 billion years ago. Correct?

15) That means that the most recent the Big Bang can have occurred is 25 billion years ago. Correct?

16) Or from statement 6, the detected part of the Universe is now roughly 50 billion light-years across, although we only see the light from when it was 25 billion light-years across. Correct?

17) And to reduce the size of universe given in statement 16 would take us back to 25 billion years ago. Correct?

18) That also means that the most recent the Big Bang can have occurred is 25 billion years ago. Correct?

19) From either 15 or 18, that means the Big Bang can not have been as recent as 14.5 billion years ago, but must have been at least 25 billion years ago. Correct?

If nobody can find a mistake in the above, which is really just adding, subtracting, and multiplying by 2, with the biggest figure in the maths being 50, then doesn't that mean that I am right? And if I am right, then doesn't that mean that the astrophysicists are wrong?

John Mendenhall
2016-Mar-30, 01:06 PM
You go off the track at about step 11,where you try to assign a size to the universe. The size of the Universe is unknown, and probably unknowable. Density is the big factor in the Big Bang, not size. Oh, and the Universe is probably infinite, and probably always has been, even at its densest.

If you intend to defend your friend's idea, and I recommend that you don't, send a private message to a moderator and ask about Against The Mainstream threads.

antoniseb
2016-Mar-30, 01:35 PM
Actually, I think steps 4 & 5 are a bit naively expressed, and could lead to misunderstanding. Everything after that is just wrongly trying to apply Newtonian mechanics to an expanding universe, in which General Relativity and arithmetic beyond linear algebra is required. So the answer to all of the "correct?" questions from then on is no, not correct. If your friend wants to come defend his/her idea, they should do it directly in the ATM section, and not try to push these non-mainstream ideas in the Q&A area.

korjik
2016-Mar-30, 01:38 PM
Hello, I'm new here and have joined to help someone out. He has a theory which we like comments upon please. There are 19 points to this theory. Thank you in advance for your help, Bluemoon16.

1) Astrophysicists tell us that the light from quasars has taken 12.5 billion years to get here travelling at the speed of light. Correct?

2) Astrophysicists tell us that quasars are detected all around us at that distance, making the detected Universe 25 billion light-years across. Correct?

3) Astrophysicists say that because it has taken the light 12.5 years to get here we see quasars how they looked 12.5 billion years ago. Correct?

4) Astrophysicists tell us that at the time the light left those quasars they were travelling away from us at just under the speed of light. Correct?

5) That means that in the 12.5 billion years that it has taken that light (from 12.5 billion years ago) to reach us, the quasars will have moved away by another almost 12.5 billion light-years. Correct?

6) If they have moved by nearly another 12.5 billion light-years that means that they are actually nearly 25 billion light-years away from us. Correct?

7) Given that we see the light from where they were 12.5 billion years ago (the light from where they are now not having reached us yet, and won't reach us for another 25 billion years) we see them where they were 12.5 billion years ago, and not where they actually are now. Correct?

8) From that lot we can say that the quasars were actually 12.5 billion light-years away from us 12.5 billion years ago. Making the Universe at that time, 12.5 billion years ago, 25 billion light-years across. Correct?

9) If we go back in time by 2 billion years, to 14.5 billion years ago, those quasars travelling at almost the speed of light would have been roughly 2 billion light-years closer, at 10.5 billion light-years away. Correct?

10) That means that 14.5 billion years ago, when the Big Bang is supposed to have happened, the quasars were 10.5 billion light-years away from where we are now in all directions, making the Universe 21 billion light-years across at that time. Correct?

11) Astrophysicists tell us that immediately after the Big Bang there was inflationary period when the Universe went from the point entity of the Big Bang to the size of a melon. Correct?

12) Given 10 and 11 that is a melon 21 billion light-years across. Correct?

13) To get back to when the Universe would have been zero across, that is, the time when it was the point entity at the time of the Big Bang, we need to go back another 10.5 billion years before the point in statement 9. Correct?

14) 10.5 billion years before 14.5 billion years is 25 billion years ago. Correct?

15) That means that the most recent the Big Bang can have occurred is 25 billion years ago. Correct?

16) Or from statement 6, the detected part of the Universe is now roughly 50 billion light-years across, although we only see the light from when it was 25 billion light-years across. Correct?

17) And to reduce the size of universe given in statement 16 would take us back to 25 billion years ago. Correct?

18) That also means that the most recent the Big Bang can have occurred is 25 billion years ago. Correct?

19) From either 15 or 18, that means the Big Bang can not have been as recent as 14.5 billion years ago, but must have been at least 25 billion years ago. Correct?

If nobody can find a mistake in the above, which is really just adding, subtracting, and multiplying by 2, with the biggest figure in the maths being 50, then doesn't that mean that I am right? And if I am right, then doesn't that mean that the astrophysicists are wrong?

None of this is anything that adding subtracting multiplying or dividing applies to. None of your points are as simple as you would make them out to be.

01101001
2016-Mar-30, 02:07 PM
Welcome to CosmoQuest to you and your calculating friend. For a fun read about other errant calculations, see: Wikipedia: Observable universe: Misconceptions on its size (https://en.wikipedia.org/wiki/Observable_universe#Misconceptions_on_its_size). It is a well-traveled road, yet beginners may easily get lost.

Grey
2016-Mar-30, 02:42 PM
All of this is a little more complicated than that. For an object that has a "lookback time" of 12.5 billion years (i.e., we see it as it was 12.5 billion years ago), we're talking about a redshift of about z = 5, given current estimates of cosmological parameters. Here (http://scitechdaily.com/galaxy-hdf850-1-as-it-was-12-5-billion-years-ago/)'s an example of an actual galaxy at that distance. But the fact that it took light about 12.5 billion years to get here doesn't mean that it was 12.5 billion light years away at that time. For z = 5, the object would have been about 4.3 billion light years* away when that light was emitted. But the light took longer than 4.3 billion years to get here, because while that light was travelling toward us, the universe was expanding. Envision an ant walking towards us while on a rubber sheet that's being stretched. The ant continues to move at standard ant-speed relative to the sheet, but the distance between us and the ant continues to increase even while the ant is walking. The comoving distance, an estimate of how far that galaxy is "right now" comes out to about 25.9 billion light years. Which makes it seem like that galaxy managed to go 21.6 billion light years in only 12.5 billion years, faster than the speed of light. For that matter, it managed to be 4.3 billion light years away when the universe was only 1.2 billion years old, which again seems faster than the speed of light.

It turns out that this works fine under general relativity, since in this case the distance is increasing due to the expansion of space, and doesn't involve two objects moving past each other at more than the speed of light. That may seem like a quibbling distinction, but it is actually an important one. Anything with a high enough redshift has an effective recession speed higher than the speed of light, and there's not a problem with that within the framework of general relativity. There's a pretty nice paper by Davis and Lineweaver (http://arxiv.org/abs/astro-ph/0310808) that discusses this in more detail.

As far as the actual size of the universe, all of this is only talking about the part of the universe we can see, the observable universe. John is right that there's pretty sound evidence that the universe is much bigger than that, and may be infinite in extent (although it also may not be; the evidence is not conclusive).

* This is actually the angular size distance, which relates to how big an object looks on the sky, and is also linked to how far away the object was when the light was first emitted. But especially for light travel times close to the age of the universe, like this one, that can only be considered a rough estimate of that initial distance, because things get even more complicated.

Reality Check
2016-Mar-30, 10:11 PM
1) Astrophysicists tell us that the light from quasars has taken 12.5 billion years to get here travelling at the speed of light. Correct?
Not correct. The current nearest quasar is IC 2497 (https://en.wikipedia.org/wiki/IC_2497) which is 730 million light years away while ULAS J1120+0641 (https://en.wikipedia.org/wiki/ULAS_J1120%2B0641) is 13.05 billion light years away. The furthest object that we have detected so far is the GN-z11 galaxy (https://en.wikipedia.org/wiki/GN-z11) at 13.4 billion light years.
N.B. These are light travel distances which have no direct physical significance in an expanding universe. The physically relevant distance has to be calculated by adding in the expansion of the universe.
This invalidates the rest of the calculation. That the calculation ignores an expanding universe invalidates it without looking at any numbers.

Interestingly incorrect is 4): All quasars and galaxies at a redshift greater than a certain value (z > 1.407 for the concordance model) are traveling away from us at a speed greater than the speed of light. (http://www.astro.ucla.edu/~wright/cosmology_faq.html#FTL)

John Mendenhall
2016-Mar-31, 01:50 AM
Not correct. The current nearest quasar is IC 2497 (https://en.wikipedia.org/wiki/IC_2497) which is 730 million light years away while ULAS J1120+0641 (https://en.wikipedia.org/wiki/ULAS_J1120%2B0641) is 13.05 billion light years away. The furthest object that we have detected so far is the GN-z11 galaxy (https://en.wikipedia.org/wiki/GN-z11) at 13.4 billion light years.
N.B. These are light travel distances which have no direct physical significance in an expanding universe. The physically relevant distance has to be calculated by adding in the expansion of the universe.
This invalidates the rest of the calculation. That the calculation ignores an expanding universe invalidates it without looking at any numbers.

Interestingly incorrect is 4): All quasars and galaxies at a redshift greater than a certain value (z > 1.407 for the concordance model) are traveling away from us at a speed greater than the speed of light. (http://www.astro.ucla.edu/~wright/cosmology_faq.html#FTL)

Hm, interesting how the a->b error kept creeping further and further back. (If a implies b, and a is false, the truth table for b is true regardless of what b is.) ATM folks stumble on this without even knowing what they are doing, and get great mileage out of it.

Bluemoon16
2016-Mar-31, 08:21 AM
Thank you. I don't defend my friend's theory. Given that it goes against absolutely every other theory I was certain it must be flawed but I don't know enough about this to be able to pinpoint it myself. Bluemoon16

Bluemoon16
2016-Mar-31, 08:26 AM
Thank you I'll check out the link. I was certain that my friend's theory must be flawed given it flies in the face of the evidence but I don't know enough about the subject to be able to evaluate it for myself. Bluemoon16

Swift
2016-Mar-31, 12:38 PM
Thank you. I don't defend my friend's theory. Given that it goes against absolutely every other theory I was certain it must be flawed but I don't know enough about this to be able to pinpoint it myself. Bluemoon16
Bluemoon16,

Just so you know, I've deleted a bunch of duplicate posts. As part of our anti-spam measures we have to keep posts from "newbies" in limbo (the "Moderation Queue") until they can be approved, and so they won't show up right away. If you continue to post, and pass the "newbie" category, it will no longer be an issue.

Bluemoon16
2016-Mar-31, 01:55 PM
I'm relatively new to forums. I'm not sure what you mean about duplicate posts, I thought I was replying individually to each of those who commented on my post and unless I was actual posting elsewhere, I'm not sure why similar comments to each of these people is a problem? Could you let me know please? Thank you Bluemoon16

Swift
2016-Mar-31, 02:29 PM
I'm relatively new to forums. I'm not sure what you mean about duplicate posts, I thought I was replying individually to each of those who commented on my post and unless I was actual posting elsewhere, I'm not sure why similar comments to each of these people is a problem? Could you let me know please? Thank you Bluemoon16
Sorry Bluemoon16, I didn't understand your intent. "Duplicate posts" are posts that seem to be the exact same, or very similar content just repeated over and over. Since we have our anti-spam measures set up the way they are, sometimes a new person won't see their post appear instantly, and they think something when wrong, and they'll just re-write the same post again and again. I assumed that was what happened here.

If you would like to reply explicitly to a particular post, the best way to do that is to go to the post you wish to reply to and in the lower right corner, click "Reply with Quote". That will put a quote of the post you are replying to in your post, and so the person you are replying to will know you were responding to them. That's exactly what I did in this post.

I hope that is clear.

John Mendenhall
2016-Mar-31, 02:45 PM
I'm relatively new to forums. I'm not sure what you mean about duplicate posts, I thought I was replying individually to each of those who commented on my post and unless I was actual posting elsewhere, I'm not sure why similar comments to each of these people is a problem? Could you let me know please? Thank you Bluemoon16

Not bad, Bluemoon, best newbie thread in quite a while.

Bluemoon16
2016-Mar-31, 03:47 PM
Sorry Bluemoon16, I didn't understand your intent. "Duplicate posts" are posts that seem to be the exact same, or very similar content just repeated over and over. Since we have our anti-spam measures set up the way they are, sometimes a new person won't see their post appear instantly, and they think something when wrong, and they'll just re-write the same post again and again. I assumed that was what happened here.

If you would like to reply explicitly to a particular post, the best way to do that is to go to the post you wish to reply to and in the lower right corner, click "Reply with Quote". That will put a quote of the post you are replying to in your post, and so the person you are replying to will know you were responding to them. That's exactly what I did in this post.

I hope that is clear.

Thank you.

George
2016-Mar-31, 06:08 PM
What the heck; I'll use my limited knowledge of BBT to help you with many of these, hopefully...

1) Astrophysicists tell us that the light from quasars has taken 12.5 billion years to get here travelling at the speed of light. Correct?

Assuming you wish to use this distance as an example, then yes. This may be the most important fact when hearing that something is such and such distance in lightyears away. It often can get confusing from here.

2) Astrophysicists tell us that quasars are detected all around us at that distance, making the detected Universe 25 billion light-years across. Correct? This statement implies that specific distance of 12.5 Glyrs. is the edge of the universe, so this part would be incorrect. The latest value for the age, thus distance in Glyrs, is 13.8 billion years, so this would be the farthest thing possible in terms of Glyrs (as we actually observe things). However, astronomers can only see light from the time it was free to travel outward. This happened about 380,000 years after the Bang when things cooled down enough for electrons to bind to the nucleus forming the first atoms, and essentially all this happened at once. This produced a flash that has redshifted ever since into the microwave band and is known as the CMB (Cosmic Microwave Background). This happens to be the best, of many, objective evidence for the Big Bang Theory.

Doubling the distance, however, is somewhat correct but only if you are clear that we are talking about the time it took the farthest light to reach us traveling from any other direction.

3) Astrophysicists say that because it has taken the light 12.5 [billion] years to get here we see quasars how they looked 12.5 billion years ago. Correct? Yes, only the light that reaches us is what we see, so it must be as it was at that time. [Interestingly, because we were much closer to it at that time, it would have appeared larger, which is what astronomers see. This apparent size oddity varies with redshift (distance).]

4) Astrophysicists tell us that at the time the light left those quasars they were travelling away from us at just under the speed of light. Correct? Probably, but, surprisingly, we can see things that were traveling even faster than the speed of light, up to a point. This is another fun, though a bit bizarre, fact about an expanding universe. Light from these objects will soon reach regions where the expansion rate is less than the speed of light (relative to us), thus it will continue toward us and reach us.

5) That means that in the 12.5 billion years that it has taken that light (from 12.5 billion years ago) to reach us, the quasars will have moved away by another almost 12.5 billion light-years. Correct? Basically, yes, but there is more to this story...

6) If they have moved by nearly another 12.5 billion light-years that means that they are actually nearly 25 billion light-years away from us. Correct?
Basically, yes. [However, the “devil is in the details”. The universe is not expanding at a rate that has, and will, never vary. Also, the universe has “shape” so you can’t exactly graph it on a flat sheet of paper. GR (General Relativity) addresses how to deal with what astronomers discover, so it gets complicated, but you are on the right track, at least how I understand BBT.]

7) Given that we see the light from where they were 12.5 billion years ago (the light from where they are now not having reached us yet, and won't reach us for another 25 billion years) we see them where they were 12.5 billion years ago, and not where they actually are now. Correct? Kinda, but in an expanding universe, the farther an object is from you, the faster it will be seen as traveling away from you, so the math gets more complicated.]

8) From that lot we can say that the quasars were actually 12.5 billion light-years away from us 12.5 billion years ago. Making the Universe at that time, 12.5 billion years ago, 25 billion light-years across. Correct? No. If the universe was static (no expansion), then this would be true (ignoring the 13.8 billion year Bang moment), but we were much closer to everything 12.5 billion years ago. (see #3)

9) If we go back in time by 2 billion years, to 14.5 billion years ago, those quasars travelling at almost the speed of light would have been roughly 2 billion light-years closer, at 10.5 billion light-years away. Correct? Though the expansion rate is almost a constant, it still means that objects you are closer to are travelling slower away from you than the more distant objects. Cut a rubber band and make an ink spot every inch along it. Then stretch the rubber band greatly in one second. Assume that you are in the middle spot, what do you notice about the speed of all the other spots? The farthest spot will have moved a much greater distance (in one second) than the closer spots, right? This is why many are confused about such things.

10) That means that 14.5 billion years ago, when the Big Bang is supposed to have happened, the quasars were 10.5 billion light-years away from where we are now in all directions, making the Universe 21 billion light-years across at that time. Correct?No. There are a couple things worth mentioning here. The Big Bang Theory begins when physics begins to work, which it does but only after a tiny, tiny portion of a second after whatever occurred at t=0. All space, as we know it, was snuggled closed, very close – nanoinches. Whatever may have been outside of our tiny universe is strictly suppositional; if it can’t be observed or tested, it is outside of the purview of science. Keep in mind that the Big Bang was a sudden and dramatic expansion of space, not an explosion within space.

11) Astrophysicists tell us that immediately after the Big Bang there was inflationary period when the Universe went from the point entity of the Big Bang to the size of a melon. Correct? Yes, but see above. You are referring to the Inflation Theory that was introduced to explain some oddities with BBT.

12) Given 10 and 11 that is a melon 21 billion light-years across. Correct? No. The melon refers to a normal sized melon. As you go back in time, the expanding universe becomes a shrinking universe.

13) To get back to when the Universe would have been zero across, that is, the time when it was the point entity at the time of the Big Bang, we need to go back another 10.5 billion years before the point in statement 9. Correct? see 12

14) 10.5 billion years before 14.5 billion years is 25 billion years ago. Correct? Fortunately, it isn’t this complicated.

15) That means that the most recent the Big Bang can have occurred is 25 billion years ago. Correct? There is only one Big Bang and it began 13.8 billion years ago. [Multiple bangs have been suggested but there are wrinkles in them with things like entropy.]

16) Or from statement 6, the detected part of the Universe is now roughly 50 billion light-years across, although we only see the light from when it was 25 billion light-years across. Correct? This is somewhat back on track. Try the links to get a more accurate value for this.

17) And to reduce the size of universe given in statement 16 would take us back to 25 billion years ago. Correct? All clocks in the universe operate at essentially the same rate (ignoring gravity wells, etc.), so reversing time will put the entire universe back to almost a singularity at 13.8 billion years ago, “mas e minus”.

If nobody can find a mistake in the above, which is really just adding, subtracting, and multiplying by 2, with the biggest figure in the maths being 50, then doesn't that mean that I am right? And if I am right, then doesn't that mean that the astrophysicists are wrong? There are significant reasons behind the claims made by astrophysicists. Since science is self-correcting due to its objectivity, astrophysicists can be shown to be wrong, but usually by other astrophysicists who can demonstrate prior errors.

Geo Kaplan
2016-Mar-31, 09:59 PM
Hello, I'm new here and have joined to help someone out. He has a theory which we like comments upon please. There are 19 points to this theory. Thank you in advance for your help, Bluemoon16.

Encourage your friend to take the time to study the subject prior to wasting any more time trying to develop a new theory. Though that is common sense, there seems to be something about cosmology that makes people feel that they can bypass the hard work of studying the subject first. There is no shortcut.

There are a great many errors (both subtle and not) in the list you've provided, some of which have been pointed out already. The age of the universe is about 13.8 billion years, while the observable universe has a diameter of almost 100 billion light-years, not the (2 x 13.8)Glyr one might compute using the same naive assumptions as in the list you presented.

The universe has been expanding all that time. So light emitted near the time of the big bang (formally, near the time of photon decoupling) has had to travel farther to get here. That's how one may reconcile the age of the universe with the observed extent of the universe.

I would direct your friend toward http://www.astro.ucla.edu/~wright/cosmology_faq.html. It is an excellent introduction to many of the important concepts your friend needs to understand before he/she can even begin to construct alternative theories. It is not possible to displace a theory that one does not understand.

Bluemoon16
2016-Apr-12, 10:48 AM
All of this is a little more complicated than that. For an object that has a "lookback time" of 12.5 billion years (i.e., we see it as it was 12.5 billion years ago), we're talking about a redshift of about z = 5, given current estimates of cosmological parameters. Here (http://scitechdaily.com/galaxy-hdf850-1-as-it-was-12-5-billion-years-ago/)'s an example of an actual galaxy at that distance. But the fact that it took light about 12.5 billion years to get here doesn't mean that it was 12.5 billion light years away at that time. For z = 5, the object would have been about 4.3 billion light years* away when that light was emitted. But the light took longer than 4.3 billion years to get here, because while that light was travelling toward us, the universe was expanding. Envision an ant walking towards us while on a rubber sheet that's being stretched. The ant continues to move at standard ant-speed relative to the sheet, but the distance between us and the ant continues to increase even while the ant is walking. The comoving distance, an estimate of how far that galaxy is "right now" comes out to about 25.9 billion light years. Which makes it seem like that galaxy managed to go 21.6 billion light years in only 12.5 billion years, faster than the speed of light. For that matter, it managed to be 4.3 billion light years away when the universe was only 1.2 billion years old, which again seems faster than the speed of light.

It turns out that this works fine under general relativity, since in this case the distance is increasing due to the expansion of space, and doesn't involve two objects moving past each other at more than the speed of light. That may seem like a quibbling distinction, but it is actually an important one. Anything with a high enough redshift has an effective recession speed higher than the speed of light, and there's not a problem with that within the framework of general relativity. There's a pretty nice paper by Davis and Lineweaver (http://arxiv.org/abs/astro-ph/0310808) that discusses this in more detail.

As far as the actual size of the universe, all of this is only talking about the part of the universe we can see, the observable universe. John is right that there's pretty sound evidence that the universe is much bigger than that, and may be infinite in extent (although it also may not be; the evidence is not conclusive).

* This is actually the angular size distance, which relates to how big an object looks on the sky, and is also linked to how far away the object was when the light was first emitted. But especially for light travel times close to the age of the universe, like this one, that can only be considered a rough estimate of that initial distance, because things get even more complicated.

Hi, I showed my friend your excellent answer pointing out his obvious errors. This is his reply, words fail me! I need to do a lot of drawings to show why your respondent is wrong about the ant on the stretching rubber sheet.

He/she assumes that the ant itself, and we, will not be affected by the expanding space-time continuum. However, if the space-time continuum is expanding in that way, then the ant, and we, being entirely within, and part of, the space time continuum, will be expanding at the same rate, and so will the Earth, and the Solar system, and the Milky Way Galaxy, and the whole Universe, so proportionality would stay the same, and we wouldn't be able to detect any difference. So the ant would not appear to be going backwards even though it is walking forwards.

If the ant is separate from the space-time continuum (which it would have to be in order to remain the same size, and that is impossible, but I'll go along with it for this sentence) then there would be a complete discontinuity between the ant's space-time and the space-time continuum, so the ant wouldn't be carried along with the expansion but stay where it was.

Either way, the ant-on-a-rubber-sheet theory fails miserably, but this will be a lot clearer with loads of drawings showing how discontinuities occur under different scenarios of what happens to objects within an expanding universe.

Bluemoon16
2016-Apr-12, 10:55 AM
Encourage your friend to take the time to study the subject prior to wasting any more time trying to develop a new theory. Though that is common sense, there seems to be something about cosmology that makes people feel that they can bypass the hard work of studying the subject first. There is no shortcut.

There are a great many errors (both subtle and not) in the list you've provided, some of which have been pointed out already. The age of the universe is about 13.8 billion years, while the observable universe has a diameter of almost 100 billion light-years, not the (2 x 13.8)Glyr one might compute using the same naive assumptions as in the list you presented.

The universe has been expanding all that time. So light emitted near the time of the big bang (formally, near the time of photon decoupling) has had to travel farther to get here. That's how one may reconcile the age of the universe with the observed extent of the universe.

I would direct your friend toward http://www.astro.ucla.edu/~wright/cosmology_faq.html. It is an excellent introduction to many of the important concepts your friend needs to understand before he/she can even begin to construct alternative theories. It is not possible to displace a theory that one does not understand.

Thanks for that. I shall let him know. Unfortunately he considers he has studied the subject [self taught!!]

Grey
2016-Apr-12, 04:08 PM
Hi, I showed my friend your excellent answer pointing out his obvious errors. This is his reply, words fail me! I need to do a lot of drawings to show why your respondent is wrong about the ant on the stretching rubber sheet.

He/she assumes that the ant itself, and we, will not be affected by the expanding space-time continuum. However, if the space-time continuum is expanding in that way, then the ant, and we, being entirely within, and part of, the space time continuum, will be expanding at the same rate, and so will the Earth, and the Solar system, and the Milky Way Galaxy, and the whole Universe, so proportionality would stay the same, and we wouldn't be able to detect any difference. So the ant would not appear to be going backwards even though it is walking forwards.

If the ant is separate from the space-time continuum (which it would have to be in order to remain the same size, and that is impossible, but I'll go along with it for this sentence) then there would be a complete discontinuity between the ant's space-time and the space-time continuum, so the ant wouldn't be carried along with the expansion but stay where it was.

Either way, the ant-on-a-rubber-sheet theory fails miserably, but this will be a lot clearer with loads of drawings showing how discontinuities occur under different scenarios of what happens to objects within an expanding universe.Systems like individual galaxies or the solar system are gravitationally bound, which is why they don't expand at the same rate as the rest of the universe. Both the gravitation of bound systems and the overall expansion are described extremely well by general relativity, and there's no conflict there. So, he's simply wrong that "if the space-time continuum is expanding in that way, then the ant, and we, being entirely within, and part of, the space time continuum, will be expanding at the same rate". But if he's reasoning from his own ideas, and isn't interested in learning or understanding general relativity or cosmology, he's not going to accept that.

I think this kind of attitude is what some people find frustrating in AtM proponents. Hundreds or thousands of extremely bright people have spent years studying cosmology, dedicating their entire careers to it. Our modern view of the universe and how it behaves has been refined over the span of more than a century, constantly comparing the predictions of our theories and models to observations to determine what works and what doesn't. And yet the AtM proponent comes in, assumes that he or she understands things better than all of those people, and does so without being willing to take the time to even really understand those theories and models. In this case, your friend is misunderstanding a number of things, and yet is trying to draw a logical conclusion that depends on all of those points being true.

If he or she really wants to discuss these things, I'd encourage your friend to join the board and discuss them "in person". And if you're confused by whether to take your friend seriously, when everyone here seems to disagree, you can take the time yourself to learn more about cosmology and astronomy (reading online, and asking questions here when something seems confusing), so that you have a better understanding of things. If you're friend won't be persuaded, don't worry about it too much. Lots of people hold mistaken beliefs, and thinking the universe is older than professional astronomers do won't really cause too many problems in life (unless you're looking for a career in astronomy, of course!).

PetTastic
2016-Apr-12, 04:09 PM
.... there seems to be something about cosmology that makes people feel that they can bypass the hard work of studying the subject first. ....

I think you must see to outsiders, not being able to explain what 80% of your inputs are does cause a credibility issue.
I think this will only change if dark matter and dark energy are found to have real basis in physics and are proved not to be correction factors.

John Mendenhall
2016-Apr-12, 04:45 PM
I think you must see to outsiders, not being able to explain what 80% of your inputs are does cause a credibility issue.
I think this will only change if dark matter and dark energy are found to have real basis in physics and are proved not to be correction factors.

I think I'm missing the point here. Who can't explain 80% of what?

Bluemoon16
2016-Apr-12, 05:09 PM
Systems like individual galaxies or the solar system are gravitationally bound, which is why they don't expand at the same rate as the rest of the universe. Both the gravitation of bound systems and the overall expansion are described extremely well by general relativity, and there's no conflict there. So, he's simply wrong that "if the space-time continuum is expanding in that way, then the ant, and we, being entirely within, and part of, the space time continuum, will be expanding at the same rate". But if he's reasoning from his own ideas, and isn't interested in learning or understanding general relativity or cosmology, he's not going to accept that.

I think this kind of attitude is what some people find frustrating in AtM proponents. Hundreds or thousands of extremely bright people have spent years studying cosmology, dedicating their entire careers to it. Our modern view of the universe and how it behaves has been refined over the span of more than a century, constantly comparing the predictions of our theories and models to observations to determine what works and what doesn't. And yet the AtM proponent comes in, assumes that he or she understands things better than all of those people, and does so without being willing to take the time to even really understand those theories and models. In this case, your friend is misunderstanding a number of things, and yet is trying to draw a logical conclusion that depends on all of those points being true.

If he or she really wants to discuss these things, I'd encourage your friend to join the board and discuss them "in person". And if you're confused by whether to take your friend seriously, when everyone here seems to disagree, you can take the time yourself to learn more about cosmology and astronomy (reading online, and asking questions here when something seems confusing), so that you have a better understanding of things. If you're friend won't be persuaded, don't worry about it too much. Lots of people hold mistaken beliefs, and thinking the universe is older than professional astronomers do won't really cause too many problems in life (unless you're looking for a career in astronomy, of course!).

Thank you. You've hit the nail on the head where you say if he's reasoning from his own ideas... I have suggested he join the forum but I doubt he will considering everyone is, quite rightly, telling him he has got things very wrong.

George
2016-Apr-12, 07:06 PM
Thank you. You've hit the nail on the head where you say if he's reasoning from his own ideas... I have suggested he join the forum but I doubt he will considering everyone is, quite rightly, telling him he has got things very wrong. Is the real reason with his reasoning a religious interpretation he is choosing to hold on to? We all tend to believe what we want to believe. If so, science won't likely resolve his real issue. The points above may cause some discomfort and possible, but not likely, some enlightenment. Last year I saw a presidential candidate state the 2nd law argues against the Big Bang Theory. It was never repeated after I sent a letter explaining the error, which I believe was the reason he stopped, though, as someone once said, "we tend to believe...." :)

Bluemoon16
2016-Apr-12, 07:20 PM
Is the real reason with his reasoning a religious interpretation he is choosing to hold on to? We all tend to believe what we want to believe. If so, science won't likely resolve his real issue. The points above may cause some discomfort and possible, but not likely, some enlightenment. Last year I saw a presidential candidate state the 2nd law argues against the Big Bang Theory. It was never repeated after I sent a letter explaining the error, which I believe was the reason he stopped, though, as someone once said, "we tend to believe...." :)

Nothing religious. His is a purely scientific [in his case, maybe I should put scientific in inverted commas] belief. He genuinely believes that he knows more about cosmology and astrophysics than everyone else, and that everyone else is wrong and that he is right.

Reality Check
2016-Apr-12, 11:49 PM
Either way, the ant-on-a-rubber-sheet theory fails miserably, ...
only if your friend has the delusion that this is an actual ant :D!
Tell your friend that the ant on a rubber sheet is an analogy that is used to visualise the situation ("Envision an ant...").
Envision a 2D rubber sheet. Think about a path from point A to point B. It will have a length. To measure the length have a 2D "ant" walk from A to B and count its footsteps. The path will be X steps long.
Now envision the same 2D sheet with the same points A and B that is being stretched in all directions. The path from A to B will now have a longer length in "ant" steps.

Cougar
2016-Apr-13, 01:30 AM
I think this kind of attitude is what some people find frustrating in AtM proponents. Hundreds or thousands of extremely bright people have spent years studying cosmology, dedicating their entire careers to it. Our modern view of the universe and how it behaves has been refined over the span of more than a century, constantly comparing the predictions of our theories and models to observations to determine what works and what doesn't. And yet the AtM proponent comes in, assumes that he or she understands things better than all of those people, and does so without being willing to take the time to even really understand those theories and models.

Quite.

korjik
2016-Apr-13, 03:35 AM
I think you must see to outsiders, not being able to explain what 80% of your inputs are does cause a credibility issue.
I think this will only change if dark matter and dark energy are found to have real basis in physics and are proved not to be correction factors.

Quantum Mechanics is a 'correction factor'.

Bluemoon16
2016-Apr-13, 10:43 AM
only if your friend has the delusion that this is an actual ant :D!
Tell your friend that the ant on a rubber sheet is an analogy that is used to visualise the situation ("Envision an ant...").
Envision a 2D rubber sheet. Think about a path from point A to point B. It will have a length. To measure the length have a 2D "ant" walk from A to B and count its footsteps. The path will be X steps long.
Now envision the same 2D sheet with the same points A and B that is being stretched in all directions. The path from A to B will now have a longer length in "ant" steps.

Good point re 'an actual ant'! I have just emailed him using two quotes from his various attempts to explain the rubber sheet business and, after those quotes, have put the only logical [nonsensical] conclusion that can be drawn from them ......
Quotes
1] In the mean time, try this: draw a galaxy (NOT just a dot) on a balloon and measure it. Now inflate the balloon (the expansion of the space-time continuum) and measure the size of the galaxy while the balloon is inflated.
Is the galaxy the same size as it was? No it isn't.
Why isn't it the same size? Because it is within the space-time continuum of the surface of the balloon, and so expands as the space-time continuum of the surface of the balloon expands.

2] He/she assumes that the ant itself, and we, will not be affected by the expanding space-time continuum. However, if the space-time continuum is expanding in that way, then the ant, and we, being entirely within, and part of, the space time continuum, will be expanding at the same rate.

My ‘conclusion’
So, if the galaxy gets bigger [part 1] and the ant also gets bigger [part 2]
that means that if I draw a galaxy on a balloon, then put an ant on one of the stars in my galaxy and then inflate the balloon, the galaxy will expand and so will the ant.

Grey
2016-Apr-13, 01:45 PM
So your friend claims that either the "ant" would have to expand with the balloon, or else it would have to stay in one place. And yet, with actual ants on a balloon, neither of those things happen. The ants don't get any bigger, and they do get further apart. So why is this, and does it have any relevance to the actual universe?*

For the first part, the ant does feel a stretching force from the surface of the balloon as it expands, trying to push its legs further apart. So why doesn't the ant get bigger? Because there are other forces (in this case, electromagnetic forces between the atoms of the ant) that are holding it together, and on a local scale, these forces are stronger than the forces from the expanding balloon. So the ant stays the same size, even while the balloon expands. Why doesn't this work the same with your friend's suggestion of a galaxy drawn on the balloon? Because in that case, he's chosen an example where those additional forces aren't present. But unlike the drawing, a galaxy does have a force keeping it together: gravity. The gravity keeping a galaxy bound is greater locally than the effect of cosmological expansion, so the galaxy stays roughly the same size (galaxies are dynamic objects, they change size and shape over time for a variety of reasons, but are more or less stable), even while space expands. Note that the galaxy is not made of the same thing that's expanding: it's not made of spacetime, it's made of matter, and spacetime is the background on which it moves and interacts. It's really more like the ant than like the drawing.

And for the second part, even though the ants aren't part of the balloon itself, the changing surface of the balloon does affect their relative distances. If there are ants just standing still, they'd be justified in claiming that their positions are not changing. And yet, for two such ants, even though neither of their positions is changing, they still get farther apart. For galaxies in spacetime, even if they aren't moving through space, the distances between them will still get larger, because the space between them is expanding.

And as a preemptive comment in case of complaining about a situation where one force can be neglected on one scale, while being dominant on a different scale, that happens all the time. For example, when looking at particle interactions at the LHC, they completely ignore gravity. It's just not relevant at that scale, because it's so much weaker than the electromagnetic and nuclear forces at short ranges. And yet, if you change your view to a larger scale, and consider the Earth's motion around the Sun, now you don't have to consider the nuclear forces at all, and gravity is completely dominant. In the same way, the effect of cosmological expansion on the scale of a person, a planet, a stellar system, or a galaxy is completely swamped by the local effects of gravity and other forces; it's not noticeable in any way. But on the scale of thousands of megaparsecs, gravity and the other forces become negligible, and cosmological expansion is dominant.

* I don't want to push the analogy further than it should be, but I think my point here does not do so.

Lucretius
2016-Apr-13, 03:06 PM
only if your friend has the delusion that this is an actual ant :D!
Tell your friend that the ant on a rubber sheet is an analogy that is used to visualise the situation ("Envision an ant...").
Envision a 2D rubber sheet. Think about a path from point A to point B. It will have a length. To measure the length have a 2D "ant" walk from A to B and count its footsteps. The path will be X steps long.
Now envision the same 2D sheet with the same points A and B that is being stretched in all directions. The path from A to B will now have a longer length in "ant" steps.

I fail to see how any of these 2D analogies have any value. Take away any one of the three physical dimensions and you're left with nothing.

George
2016-Apr-13, 04:08 PM
I fail to see how any of these 2D analogies have any value. Take away any one of the three physical dimensions and you're left with nothing. Once the simple step of seeing distance increasing with time is understood, then we can add point C (twice as far from A as B for simplicity) and show that C is moving away faster (2x) than B if we are at A. We can then chose to be at point B and note that A and C are moving away at the same rate, and from C, A is moving away at the same rate as is claimed from those at A measuring the velocity of C. The expansion rate (Hubble constant) is velocity per unit distance.

Bluemoon16
2016-Apr-13, 06:47 PM
So your friend claims that either the "ant" would have to expand with the balloon, or else it would have to stay in one place. And yet, with actual ants on a balloon, neither of those things happen. The ants don't get any bigger, and they do get further apart. So why is this, and does it have any relevance to the actual universe?*

For the first part, the ant does feel a stretching force from the surface of the balloon as it expands, trying to push its legs further apart. So why doesn't the ant get bigger? Because there are other forces (in this case, electromagnetic forces between the atoms of the ant) that are holding it together, and on a local scale, these forces are stronger than the forces from the expanding balloon. So the ant stays the same size, even while the balloon expands. Why doesn't this work the same with your friend's suggestion of a galaxy drawn on the balloon? Because in that case, he's chosen an example where those additional forces aren't present. But unlike the drawing, a galaxy does have a force keeping it together: gravity. The gravity keeping a galaxy bound is greater locally than the effect of cosmological expansion, so the galaxy stays roughly the same size (galaxies are dynamic objects, they change size and shape over time for a variety of reasons, but are more or less stable), even while space expands. Note that the galaxy is not made of the same thing that's expanding: it's not made of spacetime, it's made of matter, and spacetime is the background on which it moves and interacts. It's really more like the ant than like the drawing.

And for the second part, even though the ants aren't part of the balloon itself, the changing surface of the balloon does affect their relative distances. If there are ants just standing still, they'd be justified in claiming that their positions are not changing. And yet, for two such ants, even though neither of their positions is changing, they still get farther apart. For galaxies in spacetime, even if they aren't moving through space, the distances between them will still get larger, because the space between them is expanding.

And as a preemptive comment in case of complaining about a situation where one force can be neglected on one scale, while being dominant on a different scale, that happens all the time. For example, when looking at particle interactions at the LHC, they completely ignore gravity. It's just not relevant at that scale, because it's so much weaker than the electromagnetic and nuclear forces at short ranges. And yet, if you change your view to a larger scale, and consider the Earth's motion around the Sun, now you don't have to consider the nuclear forces at all, and gravity is completely dominant. In the same way, the effect of cosmological expansion on the scale of a person, a planet, a stellar system, or a galaxy is completely swamped by the local effects of gravity and other forces; it's not noticeable in any way. But on the scale of thousands of megaparsecs, gravity and the other forces become negligible, and cosmological expansion is dominant.

* I don't want to push the analogy further than it should be, but I think my point here does not do so.

It turns out that he was under the impression that 'the experts' [as he refers disparagingly to those who in fact know far more than he does] actually believed that the ant referred to re the rubber sheet was real!!!!! He further believed that they based their ideas about how expansion works on this 'real' ant! He quite obviously has no real idea what he's talking about so there is no point in taking this any further; I think you would agree?

Reality Check
2016-Apr-13, 10:08 PM
Good point re 'an actual ant'!
As mentioned, no one expects galaxies or stellar systems or planets or us or atoms or this "ant" to expand because they are bound systems. Frequently Asked Questions in Cosmology: Why doesn't the Solar System expand if the whole Universe is expanding? (http://www.astro.ucla.edu/~wright/cosmology_faq.html#SS)
There are about 100 observed blue-shifted galaxies (http://www.spaceanswers.com/deep-space/apart-from-andromeda-are-any-other-galaxies-moving-towards-us/). For example, the Andromeda Galaxy (https://en.wikipedia.org/wiki/Andromeda_Galaxy) is blue-shifted and likely to collide with us in ~4 billion years.

So the best balloon analogy is not galaxies = dots on the balloon. The more physical balloon analogy is galaxies = cotton tufts glued to the balloon that do not expand as the balloon expands.

As an aside: There is some evidence that atoms do not expand with an expanding universe. Light from a galaxy a billion light years away is from more than a billion years in the past when presumably atoms were smaller. That light's spectrum will include the hyperfine structure (https://en.wikipedia.org/wiki/Hyperfine_structure). These are small shifts and splitting in the spectrum lines caused by the interaction of electrons with the nucleus. We should expect that smaller atoms in the past will have different hyperfine structure from the same atoms in the present. This is not the case.

Reality Check
2016-Apr-13, 10:12 PM
It turns out that he was under the impression that 'the experts' [as he refers disparagingly to those who in fact know far more than he does] actually believed that the ant referred to re the rubber sheet was real!!!!! He further believed that they based their ideas about how expansion works on this 'real' ant! He quite obviously has no real idea what he's talking about so there is no point in taking this any further; I think you would agree?
Thinking that science is worked out using analogies rather than analogies are based on existing science does suggest some ignorance about science. If your friend is incapable of understanding this point then I agree that there is no point in taking this any further.

Bluemoon16
2016-Apr-15, 02:40 PM
So your friend claims that either the "ant" would have to expand with the balloon, or else it would have to stay in one place. And yet, with actual ants on a balloon, neither of those things happen. The ants don't get any bigger, and they do get further apart. So why is this, and does it have any relevance to the actual universe?*

For the first part, the ant does feel a stretching force from the surface of the balloon as it expands, trying to push its legs further apart. So why doesn't the ant get bigger? Because there are other forces (in this case, electromagnetic forces between the atoms of the ant) that are holding it together, and on a local scale, these forces are stronger than the forces from the expanding balloon. So the ant stays the same size, even while the balloon expands. Why doesn't this work the same with your friend's suggestion of a galaxy drawn on the balloon? Because in that case, he's chosen an example where those additional forces aren't present. But unlike the drawing, a galaxy does have a force keeping it together: gravity. The gravity keeping a galaxy bound is greater locally than the effect of cosmological expansion, so the galaxy stays roughly the same size (galaxies are dynamic objects, they change size and shape over time for a variety of reasons, but are more or less stable), even while space expands. Note that the galaxy is not made of the same thing that's expanding: it's not made of spacetime, it's made of matter, and spacetime is the background on which it moves and interacts. It's really more like the ant than like the drawing.

And for the second part, even though the ants aren't part of the balloon itself, the changing surface of the balloon does affect their relative distances. If there are ants just standing still, they'd be justified in claiming that their positions are not changing. And yet, for two such ants, even though neither of their positions is changing, they still get farther apart. For galaxies in spacetime, even if they aren't moving through space, the distances between them will still get larger, because the space between them is expanding.

And as a preemptive comment in case of complaining about a situation where one force can be neglected on one scale, while being dominant on a different scale, that happens all the time. For example, when looking at particle interactions at the LHC, they completely ignore gravity. It's just not relevant at that scale, because it's so much weaker than the electromagnetic and nuclear forces at short ranges. And yet, if you change your view to a larger scale, and consider the Earth's motion around the Sun, now you don't have to consider the nuclear forces at all, and gravity is completely dominant. In the same way, the effect of cosmological expansion on the scale of a person, a planet, a stellar system, or a galaxy is completely swamped by the local effects of gravity and other forces; it's not noticeable in any way. But on the scale of thousands of megaparsecs, gravity and the other forces become negligible, and cosmological expansion is dominant.

* I don't want to push the analogy further than it should be, but I think my point here does not do so.

Thanks. I'll tell him this but I doubt he'll accept it. I'll let you know if he has anything to say.

Bluemoon16
2016-Apr-16, 09:28 AM
So your friend claims that either the "ant" would have to expand with the balloon, or else it would have to stay in one place. And yet, with actual ants on a balloon, neither of those things happen. The ants don't get any bigger, and they do get further apart. So why is this, and does it have any relevance to the actual universe?*

For the first part, the ant does feel a stretching force from the surface of the balloon as it expands, trying to push its legs further apart. So why doesn't the ant get bigger? Because there are other forces (in this case, electromagnetic forces between the atoms of the ant) that are holding it together, and on a local scale, these forces are stronger than the forces from the expanding balloon. So the ant stays the same size, even while the balloon expands. Why doesn't this work the same with your friend's suggestion of a galaxy drawn on the balloon? Because in that case, he's chosen an example where those additional forces aren't present. But unlike the drawing, a galaxy does have a force keeping it together: gravity. The gravity keeping a galaxy bound is greater locally than the effect of cosmological expansion, so the galaxy stays roughly the same size (galaxies are dynamic objects, they change size and shape over time for a variety of reasons, but are more or less stable), even while space expands. Note that the galaxy is not made of the same thing that's expanding: it's not made of spacetime, it's made of matter, and spacetime is the background on which it moves and interacts. It's really more like the ant than like the drawing.

And for the second part, even though the ants aren't part of the balloon itself, the changing surface of the balloon does affect their relative distances. If there are ants just standing still, they'd be justified in claiming that their positions are not changing. And yet, for two such ants, even though neither of their positions is changing, they still get farther apart. For galaxies in spacetime, even if they aren't moving through space, the distances between them will still get larger, because the space between them is expanding.

And as a preemptive comment in case of complaining about a situation where one force can be neglected on one scale, while being dominant on a different scale, that happens all the time. For example, when looking at particle interactions at the LHC, they completely ignore gravity. It's just not relevant at that scale, because it's so much weaker than the electromagnetic and nuclear forces at short ranges. And yet, if you change your view to a larger scale, and consider the Earth's motion around the Sun, now you don't have to consider the nuclear forces at all, and gravity is completely dominant. In the same way, the effect of cosmological expansion on the scale of a person, a planet, a stellar system, or a galaxy is completely swamped by the local effects of gravity and other forces; it's not noticeable in any way. But on the scale of thousands of megaparsecs, gravity and the other forces become negligible, and cosmological expansion is dominant.

* I don't want to push the analogy further than it should be, but I think my point here does not do so.

He's still not convinced!!!!!!

"No one expects galaxies or stellar systems or planets or us or atoms to expand because they are bound systems."

Some people do expect them to expand, because the energy in the expansion of the space-time continuum is sufficient to force entire galaxies along faster than they would travel if the force was restricted to the explosive expansion of the Big Bang.

If it wasn't sufficient, then the expansion of the space-time continuum would simply by-pass the galaxies. As an analogy, if you place a heavy luggage trolley/galaxy in a light wind/expanding space-time continuum the trolley/galaxy stays where it is through inertia and the wind/expanding space-time continuum goes past it. To get the trolley/galaxy moving the energy from the wind/expanding space-time continuum has to be increased by increasing the force of the wind until it has sufficient energy.

To then say that such a massive force as that required to move the entire galaxy would be insufficient to expand the gap between molecules and so insufficient to cause everything within the space-time continuum to expand doesn't ring true. What you are requiring is that either objects become completely disconnected from space-time and would vanish from reality (we don't see that happening), or that the space-time continuum within objects doesn't expand, whilst the space-time around them does so.

One of two things would then happen.
Either
the time-space continuum would rupture at the junction between the expanding and non-expanding parts of the universe, which would leave the objects disconnected in a bubble with the two boundaries separated by an area with no space-time in it,
or
the boundaries would stay connected but there would be extreme distortion at the boundary.

The first option can be envisaged as a cardboard "galaxy" stuck by a small dot of glue in the middle of its back to a balloon/space-time continuum. Then draw round the "galaxy" on the balloon/space-time and draw a grid of parallel lines on the whole with several lines crossing the "galaxy". When you inflate the balloon/expand the space-time you will see the grid expand and the border that you drew round the "galaxy" move away form it leaving a clear gap all round, and which represents the area with no space-time. If that happened we would not be able to see into, or through, the area with no space-time. We can see distant galaxies so that option is obviously not reality.

The second option can be envisaged in exactly the same way, but with the entire back of the cardboard "galaxy" glued to the balloon/space-time. This time when you inflate the balloon/space time you will see that the grid lines close to the "galaxy" become distorted. They are parallel across the "galaxy", then they diverge from the edge of the "galaxy" to become parallel again some distance from it. This divergence would cause things outside of a real galaxy to appear much enlarged. We don't see that either, so that option is also not reality.

Having shown that neither option of having some non-expanding parts of the Universe matches reality, that leaves only the option that everything within the expanding space-time continuum expands along with it. The systems may be bound so that they maintain their wholeness, but it will be an expanded wholeness.

The interesting thing in this scenario, is that we would not be aware of the expansion because the relative sizes of objects in relation to each other would remain the same, so we would not see any differences. This can be demonstrated by drawing a stick man and a measuring stick of the same height next to him on a balloon and then inflating it.

When the size of the drawing has doubled, stick man and his measuring stick would still be the same size as each other, and stick man would consider that he was still the same size, one measuring stick high, as he always was. We acting as gods looking down on stick man would say that he had doubled in size, but if he could look up and see us he would consider that what had happened was that we had halved in size.

As it happens we seen no signs of ourselves expanding, which is precisely what is predicted if we are expanding along with the space-time continuum, so the evidence supports this view.

PetersCreek
2016-Apr-16, 03:51 PM
Bluemoon16,

Please have a care. Although you may not intend it, the tone and extensiveness of your last post makes it look very much like an ATM argument by proxy. This poses two problems. We do not allow ATM claims outside of the ATM forum...and we do not allow claims via proxy. If you wish to present and defend his claims, you'll need to do it in the ATM forum. If he wishes to present and defend his claims, he'll need to register and do it in the ATM forum.

Solfe
2016-Apr-16, 03:52 PM
Consider 9 seats in a square. Each seat is on casters. Every seat can move in relation to another. If the outer eight seats move outwards, neither the chair nor the person in it gets bigger yet the space between them does. Interestingly, each person sees every chair receding from them. If you had a lot more chairs, then you have an approximation for our universe and it's galaxies.

If you like the reverse, you can have two rolling chairs connected with a rope. If someone coils the rope, the chairs roll closer to each other. The chairs and the people sitting in the chairs don't shrink, but the space between them does.

profloater
2016-Apr-16, 04:06 PM
Has and it's not just space but space time . So imagine the light in the thought experiment travels at just one foot per second and that is the limit for all information. As the chairs separate you lose sight of changes not because they stopped emitting or the speed of light changed but the space time carried them away.

Bluemoon16
2016-Apr-16, 04:11 PM
Bluemoon16,

Please have a care. Although you may not intend it, the tone and extensiveness of your last post makes it look very much like an ATM argument by proxy. This poses two problems. We do not allow ATM claims outside of the ATM forum...and we do not allow claims via proxy. If you wish to present and defend his claims, you'll need to do it in the ATM forum. If he wishes to present and defend his claims, he'll need to register and do it in the ATM forum.

I didn't realise that, I posted this as part of the conversation I've been having with various people on this thread. Also, I am definitely not defending his claims. I am convinced he is wrong but I don't know enough about the subject myself to point out where he is wrong and came here for help.

PetersCreek
2016-Apr-16, 04:24 PM
I didn't realise that, I posted this as part of the conversation I've been having with various people on this thread. Also, I am definitely not defending his claims. I am convinced he is wrong but I don't know enough about the subject myself to point out where he is wrong and came here for help.

I do understand the point of this thread. Asking/answering such question is what this forum is for. However, there is a point (and not a clearly defined point, at that) where one can cross the line from just asking questions, to posting a claim on behalf of someone else...something my warning was intended to forestall. Please feel welcome to ask questions and continue the discussion but another post that looks like it could have been typed or dictated by your friend will probably cross the line again.

And another of our rules prohibits the questioning, arguing, or discussing of moderator actions within the thread. You can do that via PM, the report button, or the feedback forum.

antoniseb
2016-Apr-16, 04:25 PM
I didn't realise that, I posted this as part of the conversation I've been having with various people on this thread. ...
Just to be clear, you are welcome here, but we gave you friendly slack as a new member, and we need to stick to the rules now. I'm going to close this thread so that no one is tempted to take this over the line thread further in the wrong direction.