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Old 14th August 2022, 02:22 PM   #281
HansMustermann
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Well, it's MOSTLY absorption lines, as I was saying. I mean, there is the fact that what goes up must come down, and that goes for electron orbits too, but that doesn't preserve the direction. The new photon emitted can go in any direction, including half of them being away from you, instead of keeping coming towards you.

Of course, on the opposite side of the star the opposite would hold true, but there's a perfect black body in the way: the star. So that's why that scattering doesn't even out. If the same line is emitted as the one that's absorbed, on the average it's a loss.

I think occasionally you see emitted light too, but I'd have to study some more when that is the case. Like, it's possible that a bigger state jump comes down as two smaller ones (which still aren't directional), but I don't know off the top of my head if that can turn an absorption line into an emission line, or we're talking about some other situation or such.

(This is btw the argument that Ziggurat was trying to tell you as to why your version of tired light doesn't match observations. All mechanisms by which you'd get two lower energy photons out of one more energetic photon will scatter the light, and we just don't see that kind of scattering all the way from there to here for distant galaxies. Essentially everything would look hella foggy and attenuated if that were the case.)

Well, that is, other than for quasars and such. With those you can see light emitted by the gas around it, because it's not excited by another photon from the star per se (like happens in the atmosphere of a star), but by that massive rotating magnetic field. Well, ok, photons are involved in an electromagnetic field too, but you get the idea: those happen when the massive magnetic field hits an atom, rather than being emitted by the star and then absorbed by the atom.

Redshift, btw, is usually based on the Ly-α (Lyman-alpha) line of hydrogen before anything else. Typically that's the most used to determine red-shift, since it's the biggest jump in the spectrum, since it's based on the most abundant element in the universe. If you can do spectrography at all, you can't miss that line.
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Old 14th August 2022, 03:57 PM   #282
RecoveringYuppy
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Originally Posted by HansMustermann View Post
(This is btw the argument that Ziggurat was trying to tell you as to why your version of tired light doesn't match observations. All mechanisms by which you'd get two lower energy photons out of one more energetic photon will scatter the light, and we just don't see that kind of scattering all the way from there to here for distant galaxies. Essentially everything would look hella foggy and attenuated if that were the case.
Wasn't the first time Ziggurat did that. Might want to recall this:

http://www.internationalskeptics.com...d.php?t=348218
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Old 15th August 2022, 12:00 AM   #283
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Yeah, that's not the first time this has come along.
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Old 15th August 2022, 08:50 PM   #284
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Originally Posted by HansMustermann View Post
Well, it's MOSTLY absorption lines, as I was saying. I mean, there is the fact that what goes up must come down, and that goes for electron orbits too, but that doesn't preserve the direction. The new photon emitted can go in any direction, including half of them being away from you, instead of keeping coming towards you.

Of course, on the opposite side of the star the opposite would hold true, but there's a perfect black body in the way: the star. So that's why that scattering doesn't even out. If the same line is emitted as the one that's absorbed, on the average it's a loss.

I think occasionally you see emitted light too, but I'd have to study some more when that is the case. Like, it's possible that a bigger state jump comes down as two smaller ones (which still aren't directional), but I don't know off the top of my head if that can turn an absorption line into an emission line, or we're talking about some other situation or such.
We can tell the oxygen (for example) content of the sun by the absorption lines.

And that works for other stars, and also galaxies.

But is that true for how these elements are detected an high redshifts?

It seems to me they aren't detecting neutral gas, but ionized gas, which they can find by stronger emission lines.

https://www.aanda.org/articles/aa/fu...a13774-09.html





Quote:
(This is btw the argument that Ziggurat was trying to tell you as to why your version of tired light doesn't match observations. All mechanisms by which you'd get two lower energy photons out of one more energetic photon will scatter the light, and we just don't see that kind of scattering all the way from there to here for distant galaxies. Essentially everything would look hella foggy and attenuated if that were the case.)
Well, assuming we know all the mechanisms by which light can redshift, sure.

But this is a different topic.

The big bang being wrong, and one of my ideas being right are two different conversations.
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Old 15th August 2022, 09:06 PM   #285
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All will be revealed here:

https://iai.tv/articles/the-big-bang...ppen-auid-2215

Eric Lerner will be a speaker at our upcoming festival HowTheLightGetsIn London 2022 September 17-18 , taking part in the debate “Cosmology and the Big Bust”.
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Old 15th August 2022, 10:29 PM   #286
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Originally Posted by Mike Helland View Post
Well, assuming we know all the mechanisms by which light can redshift, sure.
No, Mike. That's what I spent pages trying to tell you, and you never learned. Any POSSIBLE mechanism for red shifting, no matter what it is, will either desync clocks or blur the image. There is no possible way around that, regardless of the details.

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The big bang being wrong, and one of my ideas being right are two different conversations.
Not really. They both stem from your fundamental ignorance of physics, and refusal to learn.
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Old 15th August 2022, 10:32 PM   #287
RecoveringYuppy
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Originally Posted by Gord_in_Toronto View Post
All will be revealed here:

https://iai.tv/articles/the-big-bang...ppen-auid-2215

Eric Lerner will be a speaker at our upcoming festival HowTheLightGetsIn London 2022 September 17-18 , taking part in the debate “Cosmology and the Big Bust”.
And when I thought this thread couldn't get more stupid.
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Old 15th August 2022, 10:43 PM   #288
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Originally Posted by Ziggurat View Post
No, Mike. That's what I spent pages trying to tell you, and you never learned. Any POSSIBLE mechanism for red shifting, no matter what it is, will either desync clocks or blur the image. There is no possible way around that, regardless of the details.

Not really. They both stem from your fundamental ignorance of physics, and refusal to learn.
Understood. This thread was not supposed to be about that. I'll start a more interesting one.
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Old 15th August 2022, 10:56 PM   #289
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Is z redshift right?

The unitless value z is what denotes redshift.

At z=1, we are half way to the beginning of time.

At z=infinity, we are at the beginning of time.

It's 1/(z+1).

So at z=2 we see the universe at 1/3 its current age. z=9 is 1/10th.

The CMB is at z=1100.

The difference between z=0 and z=1 is 7 billion years.

The difference between z=9 and z=1100 is 1.3 billion years.

A lot depends on this being right.

What if it isn't?
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Old 16th August 2022, 12:38 AM   #290
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Without going through you math: What makes you think it is not right?

Hans
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Old 16th August 2022, 03:00 AM   #291
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Originally Posted by MRC_Hans View Post
Without going through you math: What makes you think it is not right?
The math is kind important here.
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Old 16th August 2022, 03:51 AM   #292
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Originally Posted by Mike Helland View Post
The math is kind important here.
In that case, you should maybe show it.
In your OP you've put one formula, but that's it.
No math concerning Z and how it shows what it is thought of to show (and no remarks by you where, in your opnioon, the error in the maths is).

Which all comes back to the question posed to you.

Quote:
What makes you think it is not right?
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Old 16th August 2022, 03:57 AM   #293
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Originally Posted by Mike Helland View Post
The unitless value z is what denotes redshift.

At z=1, we are half way to the beginning of time.
No, that's not how z is interpreted as I understand it, though cosmology isn't my field of expertise. At z=1, the universe has expanded to half its current length scale. It would only be "half way to the beginning of time" if the expansion of the universe were linear with time, which, according to current theories, it isn't.

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Old 16th August 2022, 03:57 AM   #294
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Originally Posted by RecoveringYuppy View Post
And when I thought this thread couldn't get more stupid.
My pleasure as always.
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Old 16th August 2022, 05:59 AM   #295
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@Mike Helland
It depends on what's exciting that gas, basically. If it's light from a star behind, it's a net loss. If it's stuff like temperature or magnetic fields, it can be an emission line.
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Old 16th August 2022, 06:04 AM   #296
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Originally Posted by Mike Helland View Post
The big bang being wrong, and one of my ideas being right are two different conversations.
Well, I'm open to both. But as I was saying before, there is a lot of evidence for the big bang, than even how far we see those red-shifted galaxy. A new theory must actually show the evidence and maths that explains all that. Just "I don't understand jack squat about it, therefore it must be wrong" isn't really going to do.

Note the emphasis on maths too. It's kinda important for physics.
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Old 16th August 2022, 06:21 AM   #297
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Originally Posted by Mike Helland View Post
What if it isn't?
Answering that depends on what the evidence is of it being wrong. So, get back to us when you got that.

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Old 16th August 2022, 06:54 AM   #298
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Originally Posted by Mike Helland View Post
A lot depends on this being right.

What if it isn't?
That depends on how not right it is.

Newtonian mechanics is wrong. But most of the time, that doesn't matter. Most of the time, it's still right enough. Or to be more precise in my language, most of the time it's accurate enough.

Could the relationship between age, distance, and z be wrong? Yes. Is there reason to think that it's wildly inaccurate, or even more inaccurate than the calculated error bars? No.
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Old 16th August 2022, 07:27 AM   #299
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Originally Posted by Gord_in_Toronto View Post
All will be revealed here:

https://iai.tv/articles/the-big-bang...ppen-auid-2215

Eric Lerner will be a speaker at our upcoming festival HowTheLightGetsIn London 2022 September 17-18 , taking part in the debate “Cosmology and the Big Bust”.
I took a look at that. He mentions a paper whose title starts with "Panic!" as if that proves cosmologists and astronomers are in disarray. Now, that is indeed a strange way to start a title, so it made me curious enough to look up the paper. The full title is, "Panic! At the Disks: First Rest-frame Optical Observations of Galaxy Structure at z > 3 with JWST in the SMACS 0723 Field". Does this prove that cosmologists and astronomers are panicking? No, it proves they have a sense of humor. It's a joke reference to the music group, "Panic! At The Disco".

Everything else he wrote is basically just the fallacy that our galaxy formation models must be right and so our cosmology must be wrong, with no consideration for the possibility that our galaxy formation models could be wrong. Plus, ignoring the CMB and failing to provide any workable alternative explanation for red shifts. Which is exactly what Mike has been doing. So Mike isn't even original in his nonsensical theories.
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Old 16th August 2022, 08:24 AM   #300
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What is it with people doing bad science and then trying to tart it up with lame jokes?
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Old 16th August 2022, 08:28 AM   #301
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I think in this case it's more like failing to get the joke. Presumably because of not getting much of the science in it. And presumably also because of a dose of cognitive dissonance and wishful thinking: if they wish that the scientists are panicking, it means they must be actually panicking.
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Old 16th August 2022, 08:45 AM   #302
RecoveringYuppy
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Originally Posted by theprestige View Post
What is it with people doing bad science and then trying to tart it up with lame jokes?
Who did the bad science here? The guys who made the Panic joke are apparently doing good science. The guy who failed to get the joke is a bit off. Seems to be a bit out of his field. Not sure how is doing within his field lately either.

Eric Lerner: https://en.wikipedia.org/wiki/Eric_Lerner

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Old 16th August 2022, 09:13 AM   #303
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Originally Posted by RecoveringYuppy View Post
Answering that depends on what the evidence is of it being wrong. So, get back to us when you got that.
If z=1 is halfway to the big bang, and the dark ages are in z>1, then there should be more galaxies at z<1 than z>1. That's not looking like that's the case.

I suppose the relevant data here would be the density of galaxies at different z's.

https://iopscience.iop.org/article/1...X/830/2/83/pdf

https://astronomy.stackexchange.com/...s-per-redshift
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Old 16th August 2022, 09:15 AM   #304
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Originally Posted by RecoveringYuppy View Post
I did not previously know but I'm not surprised to find out that Lerner is a commie. Conspiratorial thinking tends to lead to errors in multiple domains of thought.
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Old 16th August 2022, 09:28 AM   #305
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Originally Posted by Mike Helland View Post
If z=1 is halfway to the big bang, and the dark ages are in z>1, then there should be more galaxies at z<1 than z>1. That's not looking like that's the case.
Why would you think that?

Quote:
I suppose the relevant data here would be the density of galaxies at different z's.

https://iopscience.iop.org/article/1...X/830/2/83/pdf

https://astronomy.stackexchange.com/...s-per-redshift
From that paper:
"The total number of galaxies in the universe is an interesting scientific question, although it may not reveal anything fundamental about the cosmology or underlying physics of the universe."

Galaxy evolution models aren't the same as cosmology. I keep telling you this, but you never learn.
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Old 16th August 2022, 09:36 AM   #306
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Originally Posted by Ziggurat View Post
Why would you think that?
if z=0 to z=1 represents the most recent 50% of the universe and z=1 to z=infinity represents the first 50%, and the first half contains the period where there were no galaxies, wouldn't we expect less galaxies at z>1 than z<1?

As z climbs, we should expect less and less galaxies until the density is zero.
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Old 16th August 2022, 09:45 AM   #307
RecoveringYuppy
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Originally Posted by Mike Helland View Post
If z=1 is halfway to the big bang, and the dark ages are in z>1, then there should be more galaxies at z<1 than z>1.
If you really want your misconceptions corrected you need to show your work and your sources.
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Old 16th August 2022, 09:47 AM   #308
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Originally Posted by Mike Helland View Post
if z=0 to z=1 represents the most recent 50% of the universe and z=1 to z=infinity represents the first 50%, and the first half contains the period where there were no galaxies, wouldn't we expect less galaxies at z>1 than z<1?

As z climbs, we should expect less and less galaxies until the density is zero.
No.
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Old 16th August 2022, 09:59 AM   #309
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Originally Posted by Mike Helland View Post
if z=0 to z=1 represents the most recent 50% of the universe and z=1 to z=infinity represents the first 50%, and the first half contains the period where there were no galaxies, wouldn't we expect less galaxies at z>1 than z<1?
That might make sense if there was no mechanism to reduce the number of galaxies over time. But there is: galaxy mergers. Which your source talks about, but you seem to have ignored.

You have a habit of never actually understanding your own links. One wonders if you even read them.
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Old 16th August 2022, 10:03 AM   #310
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Originally Posted by Ziggurat View Post
That might make sense if there was no mechanism to reduce the number of galaxies over time. But there is: galaxy mergers. Which your source talks about, but you seem to have ignored.
Yeah, in the first half of the universe.

Page 10:

"One of the major results we find is that the total number
density of galaxies in the universe declines with time from from
high to low redshift when using a M * =10 6 M e limit. In fact,
what we find is that measured mass functions down to a limit of
M * =10 6 M e give a total number density that declines by a
factor of 10 within the first 2 Gyr of the universe’s history, and
a further reduction at later times. This decline may further level
off between redshifts of z= 1 and z=2."
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Old 16th August 2022, 10:17 AM   #311
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Why exactly would you expect "expect less galaxies at z>1 than z<1?"

I mean, even as of the latest message (#14), you seem to even confuse density with total number.

Quick question: if I draw a circle of radius r2=2, and a concentric one of radius r1=1, what's the ratio between the surface of the radius 1 circle and the band between 1<r<=2? (Spoiler: 3.)

Well, ok, in this case the distance for z=1 is about 7.7 light years, and the maximum distance we can see us for HD-1 which is approximately 13.5 light years. (Back when that light was emitted.) So the surface ratio between the inner circle and the outer band is only approximately 2.

But wait, we're actually talking spheres, not flat circles. So we're talking volume. In which case the outer band has 4.4 TIMES the volume of the inner sphere.

So, you know, even if the density had stayed constant, which it didn't, you'd still multiply that density by 4.4 times more volume for z>1 than for z<1.
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Old 16th August 2022, 10:27 AM   #312
Mike Helland
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Originally Posted by HansMustermann View Post
Why exactly would you expect "expect less galaxies at z>1 than z<1?"

I mean, even as of the latest message (#14), you seem to even confuse density with total number.

Quick question: if I draw a circle of radius r2=2, and a concentric one of radius r1=1, what's the ratio between the surface of the radius 1 circle and the band between 1<r<=2? (Spoiler: 3.)
I guess I am pretty dumb. Somehow I get 2.

Quote:
Well, ok, in this case the distance for z=1 is about 7.7 light years, and the maximum distance we can see us for HD-1 which is approximately 13.5 light years. So the surface ration between the inner circle and the outer band is only approximately 2.

Even if the density stayed constant, which it didn't (because of those mergers), even a middle-schooler who hasn't slept in maths class should be able to figure out to expect twice as many at z>1.
If 0>z>1 represents 50% of the universe, and 1>z>2 represents 16.6% of the universe, in which range would one expect to find more galaxies?

4>z>5 is 1/5 - 1/6, or 3.33% of the universe. How many of the universe's galaxies should we expect in that range? 3.33%, right?
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Old 16th August 2022, 10:28 AM   #313
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Originally Posted by Mike Helland View Post
Yeah, in the first half of the universe.
But you don't understand why that still matters to your claim.

You aren't very good at math. Or logic.
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Old 16th August 2022, 10:36 AM   #314
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Originally Posted by Mike Helland View Post
I guess I am pretty dumb. Somehow I get 2.
Area, not circumference. But even with that mistake, the point is it's not 1. Can you understand why that's significant?

No, probably not.

Quote:
4>z>5 is 1/5 - 1/6, or 3.33% of the universe. How many of the universe's galaxies should we expect in that range? 3.33%, right?
Wrong.
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Old 16th August 2022, 10:37 AM   #315
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Originally Posted by Ziggurat View Post
Wrong.
Ok then.

How many of the universe's galaxies should have a z between 4 and 5?
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Old 16th August 2022, 10:44 AM   #316
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Volume of a sphere is V = 4/3 πr3. Power of 3. So yes, a sphere with the radius of 13.5 billions of light years, has a volume 5.4 times higher than one with a radius of 7.7 billion light years. Take the difference and you have 4.4 times more volume in the outer band than in the inner sphere.

In fact, even if the density of galaxies were to increase linearly between the 13.5 billion years ago and present (IRL it decreased), you'd STILL have more stars above z=1 than below z=1.

But yeah, it seems like we were wrong about what the problem with these threads was. I thought it was "I don't understand advanced astrophysics, so I think I'm smarter than the scientists who do", when in fact it turns out to be more of a case of "I don't understand even middle school geometry, so I think I'm smarter than the scientists"
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Old 16th August 2022, 10:46 AM   #317
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Originally Posted by Ziggurat View Post
Area, not circumference. But even with that mistake, the point is it's not 1. Can you understand why that's significant?
Actually, technically his answer would be wrong even for circumference, since the problem asked for the difference.
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Old 16th August 2022, 10:50 AM   #318
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Originally Posted by HansMustermann View Post
Volume of a sphere is V = 4/3 πr3. Power of 3. So yes, a sphere with the radius of 13.5 billions of light years, has a volume 5.4 times higher than one with a radius of 7.7 billion light years. Take the difference and you have 4.4 times more volume in the outer band than in the inner sphere.
I thought you were talking about circles with radius of 1 and 2.

In any case, the volume's you are comparing here have a z of 1 and infinity.

The CMB is at z=1100, so there aren't galaxies between then and z=infinity.
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Old 16th August 2022, 10:51 AM   #319
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Originally Posted by HansMustermann View Post
Actually, technically his answer would be wrong even for circumference, since the problem asked for the difference.
You asked for the ratio.

It's easy to make someone look silly when you flat up lie.
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Old 16th August 2022, 11:06 AM   #320
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Originally Posted by Mike Helland View Post
Ok then.

How many of the universe's galaxies should have a z between 4 and 5?
That depends on stuff like galaxy merger rates, and we don't have any theoretical models for stuff like that which are independent of observations. So there's basically no way of predicting that with any accuracy, we need to measure that in order to inform our models.
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