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Blind Watchmaker

Can we see a correlation between the Cosmic microwave background map and the visible universe?

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Hi all,

I guess that all of you familiar with this picture of the Cosmic microwave background map:

https://upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Ilc_9yr_moll4096.png/1920px-Ilc_9yr_moll4096.png

But is there a strong correlation between this map and the current visible universe?

Can we really see stars and galaxies in the red spots, and an empty space (without stars and matter) in the azure and blue areas?

Shouldn't we see such correlation?

Thanks!

 

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That is a temperature 'map' from over 13.5 billion years ago.

Features on that map would have been 'seeds' for present features.
But you won't see a correlation between features ( like maybe galaxies/clusters but certainly not stars ) and differently colored ( temperature ) areas.

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10 hours ago, MigL said:

That is a temperature 'map' from over 13.5 billion years ago.

Features on that map would have been 'seeds' for present features.
But you won't see a correlation between features ( like maybe galaxies/clusters but certainly not stars ) and differently colored ( temperature ) areas.

But why wouldn't we see a correlation between the cosmic microwave background map and the current state of the universe?

If I understand it right, the different colors in this map represent different temperatures, which represent different density of matter in the early universe, so I would expect that for example in the red areas of the map, which represents high density of matter, we will find (today) clusters of galaxies, and that in the blue areas which represent low density of matter, we will find an empty space with almost no dust and not galaxies.

Where am I wrong?

 

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I don't think you are wrong.  The cold areas DO correspond to voids, and warmer areas DO correspond to regions where there are galaxies.

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Those variances you see ( as color ) evolved after 300000 years.
It has been approximately 13500000000 years since then.
Do you think not much has changed ???

From the latest measurements, once you subtract the dipole anisotropy ( due to the sun/galaxy motion against the relatively fixed CMBR background ), you are left with a variance of 0.0002 deg K. Just because they seem so much different when they are colored red and blue, does not mean there is more than a couple of parts in 10000 difference.

https://wmap.gsfc.nasa.gov/universe/bb_cosmo_fluct.html

The variances have value in the study of structure formation, but I really don't think you can point to a particular area and say " this cooler/denser area has become this particular galactic cluster" or "This hotter area has become this particular void".

Edited by MigL

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45 minutes ago, MigL said:

Those variances you see ( as color ) evolved after 300000 years.
It has been approximately 13500000000 years since then.
Do you think not much has changed ???

From the latest measurements, once you subtract the dipole anisotropy ( due to the sun/galaxy motion against the relatively fixed CMBR background ), you are left with a variance of 0.0002 deg K. Just because they seem so much different when they are colored red and blue, does not mean there is more than a couple of parts in 10000 difference.

https://wmap.gsfc.nasa.gov/universe/bb_cosmo_fluct.html

The variances have value in the study of structure formation, but I really don't think you can point to a particular area and say " this cooler/denser area has become this particular galactic cluster" or "This hotter area has become this particular void".

That is very interesting, since I had always assumed, when looking at the CMB map, that the blue "cold" regions would become voids and the red "warmer" regions were where stars and galaxies would form.  And yet you said "cooler/denser area" may have corresponded to a galactic cluster, and the warmer areas became voids.  Then I found this on Wikipedia where a great cold spot is thought to be a great void.

"The CMB Cold Spot or WMAP Cold Spot is a region of the sky seen in microwaves that has been found to be unusually large and cold relative to the expected properties of the cosmic microwave background radiation (CMBR). 

Various alternative explanations exist, including a so-called Eridanus Supervoid or Great Void."

https://en.wikipedia.org/wiki/CMB_cold_spot

On this map you see colors ranging from blue to red with yellow and green in between.

https://www.bing.com/search?q=wmap+microwave+sky&FORM=R5FD2

 

 

Edited by Airbrush

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Could be I have it backwards...
Just going by gas laws, cooler would indicate denser.

Edit:
Going by your link, there are various possible explanations.
If there was a correlation between the "cold' spot and the supervoid, the other possibilities would be easily eliminated.
Instead, it seems, since the discovery evidence has mounted against a correlation ( also from your link ).
And this is a single anomaly in the gaussian temp distribution.
Where are the other correlation indicators ?

Edited by MigL

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Cooler indicates less dense. A higher density would be hotter. Hence at time of CMB the mean average temperature was roughly 3000 CMB. Temperature drops on the inverse of the scale factor a.

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Sorry Mordred.
Edited my post after you replied.
I stand corrected.

Edited by MigL

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1 hour ago, MigL said:

Those variances you see ( as color ) evolved after 300000 years.
It has been approximately 13500000000 years since then.
Do you think not much has changed ???

From the latest measurements, once you subtract the dipole anisotropy ( due to the sun/galaxy motion against the relatively fixed CMBR background ), you are left with a variance of 0.0002 deg K. Just because they seem so much different when they are colored red and blue, does not mean there is more than a couple of parts in 10000 difference.

https://wmap.gsfc.nasa.gov/universe/bb_cosmo_fluct.html

The variances have value in the study of structure formation, but I really don't think you can point to a particular area and say " this cooler/denser area has become this particular galactic cluster" or "This hotter area has become this particular void".

Yes, I know that this map shows how the universe looked like 380,000 years after the Big Bang, but still, I thought that there should be a nice correlation between this and the current state of the universe. My intuition tells me that at least statically, we should find more galaxies clusters in the areas with lot of red color on the right side of the map:

 

1920px-Ilc_9yr_moll4096.png

 

and much less galaxies and matter on the middle where you see the large cold blue area (or the opposite, I wasn't follow).

 

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No the mass distribution is homogeneous and isotropic. Homogeneous is no preferred location and isotropic is no preferred direction. In essence the distribution is uniform when both the above is involved 

 However one must look on scales  roughly 100 Mpc. This will even out the large scale clusters such as galaxies etc. (Averages to the above).

Those temperature differences you see on that map is only 1/1000's of a degree difference. In essence incredibly uniform. The image would correlate early LSS such as galaxy cluster  filaments in early development.

Edited by Mordred

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12 hours ago, Mordred said:

No the mass distribution is homogeneous and isotropic. Homogeneous is no preferred location and isotropic is no preferred direction. In essence the distribution is uniform when both the above is involved 

 However one must look on scales  roughly 100 Mpc. This will even out the large scale clusters such as galaxies etc. (Averages to the above).

Those temperature differences you see on that map is only 1/1000's of a degree difference. In essence incredibly uniform. The image would correlate early LSS such as galaxy cluster  filaments in early development.

Very interesting.  Here are a few questions:

How many light years is one Mpc?

What is "LSS"?

Do you agree that on the color diagram (above) the dark blue areas would evolve into voids, and the warmest areas are red where more matter exists and where galaxies would evolve?

On the map the great, dark-blue region in the middle resembles the Atlantic Ocean (is this where the Great Cold Spot is?) with N & S Americas to the left and Europe/Africa to the right.

Edited by Airbrush

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2 minutes ago, Airbrush said:

How many light years is one Mpc?

3.262e+6
 

5 minutes ago, Airbrush said:

What is "LSS"?

Large scale structure 

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4 minutes ago, iNow said:

3.262e+6
 

Large scale structure 

Do you mean that one million parsecs is about 3.26 million light years?  That would mean one parsec is about 3.26 light years.

Thanks!

Edited by Airbrush

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24 minutes ago, Airbrush said:

That would mean one parsec is about 3.26 light years.

Correct

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