Galaxy cluster at z=4.31

ALMA sees very far. And at z=4.31, just 1.4 Gy after the supposed
"bang"... it sees a galaxy cluster the mass of the coma cluster...

http://www.eso.org/public/archives/r...2/eso1812a.pdf

Interesting read that article.

Now, wait a minute. If that huge concentration of mass existed 1.4Gy
after the "beginning" we should see an object in the CMB isn't it?

If we look at that particular direction, do we see a change in the
composition of the CMB?

1.4 Gy after the big bang, that huge concentration of mass hasn't the
time to move a lot, and should be there as a variation of the CMB light.

If we take the CMB measurements of the Planck satellite, at that
particular point in our horizon we should see this object.

What is more interesting, besides the death of the nth cosmology we have
produced, is that there is apparently an evolution or rather a change.
Galaxies were much younger 12.7 Gy ago. And this forming cluster, that
was already a heavyweight at that time, must be a gargantuan object now.

The team identified 14 galaies, and they are producing stars at an
incredible rate... the excesses of youth. :-)

But can we extrapolate from a few objects to an universal evolution?

Difficult. Until a lot of more observations are done, nobody can say
with any satatistical relevance that "the universe" and galaxies were
"younger" at that time. This is a young object, but observer bias is a
reality: it is quite bright of course, given its huge dimensions and
star formation rates. Other objects, less luminous, could be there and
they could be old objects already then, 12.7 Gy ago.

In any case, this is not just a galaxy (as I have repeatedly reported in
this group) at this enormous distances that poses a huge problem. It is
a CLUSTER of them... with an incredible mass. Clusters weren't supposed
to exist before 10Gy ago. Now we find one at more than 12Gy!