New problems for current cosmology

As the observable Universe expands, more problems arise for the current
cosmology.

Researches at Caltech have discovered the oldest galaxy yet to be found
at z = 8.68!

quote from http://www.sciencedaily.com/releases/2015/09/150904144505.htm
"The surprising aspect about the present discovery is that we have
detected this Lyman-alpha line in an apparently faint galaxy at a
redshift of 8.68, corresponding to a time when the universe should be
full of absorbing hydrogen clouds," Ellis says. Prior to their
discovery, the farthest detected galaxy had a redshift of 7.73.
end quote

The scientific article is at
arXiv:1507.02679v3 [astro-ph.GA] 13 Aug 2015

Of course there is even more in the works: The article
arXiv:1502.05681v2 [astro-ph.GA] 22 Feb 2015 reads:

quote
We report on our first set of spectroscopic Hubble Space Telescope
observations of the z = 11 candidate galaxy strongly lensed by the
MACSJ0647.7+7015 galaxy cluster. The three lensed images are faint and
we show that these early slitless grism observations are of sufficient
depth to investigate whether this high-redshift candidate, identified by
its strong photometric break at 1.5mm, could possibly be an emission
line galaxy at a much lower redshift. While such an interloper would
imply the existence of a rather peculiar object, we show here that such
strong emission lines would clearly have been detected. Comparing
realistic, two-dimensional simulations to these new observations we
would expect the necessary emission lines to be detected at 5 sigma
while we see no evidence for such lines in the dispersed data of any of
the three lensed images. We therefore exclude that this object could be
a low redshift emission line interloper, which significantly increases
the likelihood of this candidate being a bona fide z = 11 galaxy.
end quote

We are then approaching z=11! There is NO sign of the announced "dark
ages" where the "primitive" universe should have contained neutral
hydrogen that should block the Ly-alpha emission.

Note that we are at only 420 MY (z=11) after the supposed bang and we
still see fully formed galaxies floating around. And at least with
z=8.68 we can still see the Ly-alpha emission.

Fully formed galaxies after only 420 MY after the big bang is very
difficult to imagine. The time needed to form a SINGLE star is 50 MY.

Yes, it could be that all the stars of that galaxy at z=11 were formed
almost simultaneously, anything can be explained away. But is it
feasible that star forming regions of such a size that they build a
whole galaxy in a few hundred million years exist?

Note that at z=30 (100MY after the BB) the CMB is still 83.7 K, much too
hot still to condense stars, in my humble opinion.

So, the first 150-200 MY are unusable. After the bang the Universe
should cool enough to build stars.

All those stars must have formed "instanstaneously" in around 100-200
million years. And that was happening in all galaxies at z=11 at the
same time. It would be surprising that MACSJ0647.7+7015 was the only
galaxy of the universe at z=11.

The galaxy at z=11 is a lensed galaxy. That means that an enormous
number of such galaxies must exist so that we have in a per chance
alignment the opportunity to see a galaxy exactly at the right place in
the gravitational lens that concentrates the light of that galaxy in our
direction.

Some years ago I "predicted" that the further that we see, we will see
more of the same: galaxies, stars, clusters. There will be no trace of
the supposed cosmology.

The observation of the Ly-alpha emission from that galaxy confirms this.
And we will see more confirmations in the future.

In article ,
jacobnavia writes:
Researches at Caltech have discovered the oldest galaxy yet to be found
at z = 8.68!
arXiv:1507.02679v3 [astro-ph.GA] 13 Aug 2015

and

arXiv:1502.05681v2 [astro-ph.GA] 22 Feb 2015 reads:
We report on our first set of spectroscopic Hubble Space Telescope
observations of the z = 11 candidate galaxy strongly lensed by the
MACSJ0647.7+7015 galaxy cluster.

Both very nice work.

We are then approaching z=11! There is NO sign of the announced "dark
ages" where the "primitive" universe should have contained neutral
hydrogen that should block the Ly-alpha emission.

Robertson et al. (2015 ApJL 802, L19) disagree with you. See their
Fig 3. The neutral fraction for z6 is uncertain but substantial,
much larger than the local value. Perhaps more directly relevant,
Finkelstein et al. (2013 Nature 502, 524) observed 43 high-redshift
galaxies of which only one showed an emission line. Zitrin et
al. (the first preprint above) don't seem to say how many galaxies
they observed to find one with a line, but I'd be surprised if it's a
small number. The upshot is that there is very good evidence for the
"dark ages," but a few lines of sight are not completely opaque.

Note that we are at only 420 MY (z=11) after the supposed bang and we
still see fully formed galaxies floating around.

What do you mean by "fully formed," and why do you think these high
redshift galaxies fit that category?

The time needed to form a SINGLE star is 50 MY.

Why do you think that?

But is it
feasible that star forming regions of such a size that they build a
whole galaxy in a few hundred million years exist?

Measured star formation rates for observed z=7 galaxes, though very
uncertain, tend to be of order 100 solar masses per year, and the
highest masses (better known but still uncertain) are around 8E9
solar masses. Care to work out the time it takes to form them?

Note that at z=30 (100MY after the BB) the CMB is still 83.7 K, much too
hot still to condense stars, in my humble opinion.

Current guesses are that the first galaxies probably formed around
z=15, but there's no evidence of that so far. I know how to find the
evidence if someone wants to put up about $800M. :-) What is known is
that the space density of galaxies declines very rapidly as redshift
increases. In other words, galaxy numbers increased very rapidly
with time from redshift 8 onward. At higher redshifts there are too
few galaxies known to estimate the space densities, but the trend of
fewer galaxies at higher redshift almost certainly continues.

It would be surprising that MACSJ0647.7+7015 was the only
galaxy of the universe at z=11.

Indeed it would, but it would be equally surprising if galaxy numbers
at z=11 are not far smaller than at z=8.

--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA

In article , jacobnavia
writes:

Researches at Caltech have discovered the oldest galaxy yet to be found
at z = 8.68!

Note that, in terms of time, the difference between z=0 and z=1 is much
greater than between z=7 and z=8.

Note that we are at only 420 MY (z=11) after the supposed bang and we
still see fully formed galaxies floating around.

Who says that they are "fully formed"?

Le 12/09/2015 16:25, Phillip Helbig (undress to reply) a écrit :
In article , jacobnavia
writes:

Researches at Caltech have discovered the oldest galaxy yet to be found
at z = 8.68!

Note that, in terms of time, the difference between z=0 and z=1 is much
greater than between z=7 and z=8.


I know Mr Helbig, everyone knows that, even me. But you skipped all the
points I made, telling a fact that has nothing to do with the points I
raised.

Note that we are at only 420 MY (z=11) after the supposed bang and we
still see fully formed galaxies floating around.

Who says that they are "fully formed"?


I do not know FOR SURE, but hm...

The light from that galaxy is coming to us from a distance of more than
13 200 000 000 light years... Obviously it is a baby galaxy since the
universe should have been only 600 million years old.

But to shine that brightly so that its light reaches us, it was quite
big excuse me. Incredibly big and spriging into life in a mere 0.5 Gy!!!

And this is just a little problem for current cosmology. The real test
is behind that galaxy.

The SEA OF GALAXIES that is waiting for us behind this one. An
astronomer had the good idea of looking at the background of the Hubble
photographs... It looks "grainy"... isn't it?

That is the end of current cosmology.

We arrive at the sea, and all our theories drown in it.

jacob

[[Mod. note -- I'm approving this posting with some reluctance, as our
newsgroup charter forbids "'because I say so' speculations". You haven't
given any theoretical argument here for *why* forming a galaxy in less
than 0.5Gyr is a problem.
-- jt]]

Le 12/09/2015 04:39, Steve Willner a écrit :
The time needed to form a SINGLE star is 50 MY.
Why do you think that?


http://science.nasa.gov/astrophysics...rm-and-evolve/

A star the size of our Sun requires about 50 million years to mature
from the beginning of the collapse to adulthood.


Etc. Extremely massive stars take only a few hundred thousand years.

I know where you are going: The extreme conditions right after the big
bang, etc, all the stars in that galaxy were extremely massive.

That should be seen in a spectrum of that galaxy that corresponds to a
blue color since all the stars that shine are huge and form quickly.

I just think that that will not be the case.

We have just to wait confirmation/non confirmation.

jacob

[[Mod. note -- These 1st-generation stars (known as "population III",
a(nother) example of an infelicitious name that by now we're stuck with)
were indeed very massive (because they're forming from almost pure
hydrogen+helium, with only tiny traces of heavy elements). But that
means that these stars will have very short lifetimes, so within a
few million years of formation each such star will end its life, probably
with a supernova. The next round of star formation will then proceed
from an interstellar medium with nontrivial heavier-element concentration,
leading to a less "top-heavy" mass spectrum. Figuring out the resulting
overall color (low-resolution spectrum) of a galaxy full of these things
after a few 10s or 100 million years is a nontrivial problem (I think
this usually goes by the name "population synthesis).

I believe one of JWST's key science goals is to do spectroscopy of such
(very faint) high-redshift galaxies. That should tell us a lot... once
JWST is launched/debugged/commissioned. Hopefully that's 2019-2020 or
thereabouts.

We should also get a lot of really good data (a lot more photons!) from
the next generation of 30-40m-aperature ground-based telescopes, planned
for first-light around 2022-2025.
-- jt]]

Le 12/09/2015 04:39, Steve Willner a écrit :
What is known is
that the space density of galaxies declines very rapidly as redshift
increases. In other words, galaxy numbers increased very rapidly
with time from redshift 8 onward. At higher redshifts there are too
few galaxies known to estimate the space densities, but the trend of
fewer galaxies at higher redshift almost certainly continues.

http://www.sciencedaily.com/releases...0909091229.htm
quote
In a research paper published today in Nature Communications, the team
describes its use of a new statistical method to analyze Hubble Space
Telescope data captured during lengthy sky surveys. The method enabled
the scientists to parse out signals from the noise in Hubble's deep-sky
images, providing the first estimate of the number of small, primordial
galaxies in the early universe. The researchers concluded that there are
close to 10 times more of these galaxies than were previously detected
in deep Hubble surveys.
end quote


There is a sea of galaxies beyond the ones we perceive now.

The farther we see, the more galaxies we see.

Le 13/09/2015 05:45, jacobnavia a écrit :
[[Mod. note -- I'm approving this posting with some reluctance, as our
newsgroup charter forbids "'because I say so' speculations". You haven't
given any theoretical argument here for*why* forming a galaxy in less
than 0.5Gyr is a problem.
-- jt]]

OK. Let's suppose that the article I cited about that galaxy at z=11 is
confirmed (arXiv:1502.05681v2 [astro-ph.GA] 22 Feb 2015)

We are then at 420 million years after the supposed bang. The CMB at
this time is still around 32K.

When did that galaxy start its star formation?

At t=100 million years we have the CMB at 84.63 Kelvins, much too hot to
form stars. Note that stars (and galaxies) are formed by gravitational
interaction and that the gravitational field is very weak.

A hot gas can't collapse gravitationally because gravity can't
counterbalance the kinetic energy of the gas particles. That situation
is made worst by the absence of grains and heavy elements that could be
used as condensation helpers. According to the BB theory there were only
gases at that time.

At z=20 (t=180 MY) we have a colder situation around 57,33 Kelvins, so
let's start there. We can suppose that the first molecular clouds
collapse in the early universe started about t=180 MY. Then we have

420-180 -- 240 MY.

In only 240 MY that galaxy formed so many billions of stars that its
light reaches us (granted, lensed by a gravitational lens, I will come
back to this later) crossing 13 200 000 000 light years of space!!

In 240 Million Years???

Normal stars like the sun take 50 MY to form. Huge stars take a few
hundred thousand years. Now:

1) It can be possible to form a huge galaxy in 240 MY if all the stars
are HUGE stars that build in much less than a million years.

2) If that is the case the light of that galaxy should be highly blue.
This is the observational test for this hypothesis that would save the
BB theory.

3) Problems with that, is that a sudden "explosion" building billions of
stars in such a short time would considerably heat the gas in that
galaxy, making further star formation very difficult. Star formation is
a process that disrupts star formation. Stars destroy their molecular
clouds once born.


And another problem (this one fatal) is the following: How come that we
can see that galaxy at all? A chance alignment? That galaxy is exactly
at the right position behind a cluster of galaxies in the foreground.

That give us a hint that galaxies at z=11 are SO numerous that we can
find easily one that is at the right position. This give us a hint that
the new observations with Hubble that I cited are right:

There is a sea of galaxies at z=11. So plenty of galaxies that we are
bound to find one that lenses through that cluster.

It is the observation of this galaxy background (that we are getting
hints now) and will be made shortly, that will definitely kill BB
theory. See

http://www.sciencedaily.com/releases...0909091229.htm

We know nothing about the Universe because we haven't seen anything yet.
13-14 Bilion years is nothing compared to that background sea that is
waiting for us.

In article ,
jacobnavia writes:
http://science.nasa.gov/astrophysics...rm-and-evolve/
A star the size of our Sun requires about 50 million years to mature
from the beginning of the collapse to adulthood.

I don't understand that assertion. Maybe they are taking an
extremely early moment as "the beginning of the collapse." Regardless
of that, star formation in the Milky Way (which is what the statement
refers to) must be quite different from star formation in distant
galaxies because the physical conditions are entirely different. In
particular, the initial collapsing clouds are likely far more massive
than typical molecular clouds in the Milky Way. (Look up "Jeans
mass" to see why.)

Etc. Extremely massive stars take only a few hundred thousand years.

Which is the more relevant time scale.

I know where you are going: The extreme conditions right after the big
bang, etc, all the stars in that galaxy were extremely massive.

Not necessarily "all the stars," but certainly "all the stars that
produce the light we observe." The longest wavelength observed
(excluding ALMA observations, which don't show starlight, of a few)
for any of these galaxies is 4.5 microns. Divide that by 1+z to get
the emitted wavelength. Stars less than a couple of solar masses
contribute nothing to the light we can see.

That should be seen in a spectrum of that galaxy that corresponds to a
blue color since all the stars that shine are huge and form quickly.

In most cases, the observed continuum slope is fairly blue.

[[Mod. note -- These 1st-generation stars (known as "population III",
....
Figuring out the resulting
overall color (low-resolution spectrum) of a galaxy full of these things

More generally, figuring out the "initial mass function" even for
nearby galaxies is nearly impossible. The stars we can detect in any
galaxy are the most massive ones that exist in the population, and
the number of less massive stars is _assumed_ based mostly on what's
known locally. (I'm being a little over-pessimistic here for effect
but not much.)

--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA

In article ,
jacobnavia writes:
http://www.sciencedaily.com/releases...0909091229.htm
quote
In a research paper published today in Nature Communications,

The UCI press release is at
http://news.uci.edu/press-releases/p...iest-galaxies/
and a preprint of the article is at
http://arxiv.org/abs/1509.02935

providing the first estimate of the number of small, primordial
galaxies in the early universe. The researchers concluded that there are
close to 10 times more of these galaxies than were previously detected
in deep Hubble surveys.

Not the first estimate by any means. The reported results are
tentative and model dependent but no great surprise. If there are
some number of luminous galaxies, one expects much larger numbers of
galaxies of lower luminosity. It's actually those galaxies, not the
most luminous ones, that reionize the universe, so they have to be
there. _Detecting_ them is a much harder matter -- one of the prime
goals of JWST -- and I wouldn't say this paper has done it yet
because the uncertainties are so large. But they have to be there
unless we have a huge surprise in store.

--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA

In article , jacobnavia
writes:

And another problem (this one fatal) is the following: How come that we
can see that galaxy at all? A chance alignment? That galaxy is exactly
at the right position behind a cluster of galaxies in the foreground.

Where is the problem? This is standard stuff, going back to at least
the paper by Turner, Ostriker and Gott. One can calculate the
probability that a distant galaxy is lensed by a closer one and/or a
cluster. Of course it is a chance alignment, but that doesn't means it
can't happen. It is improbable for any person to win the lottery, yet
someone wins every week.

You seem to be implying that a "chance alignment" is improbable unless
your sea of galaxies exists. You need some maths to back that up.

Keep in mind that cosmology is pretty straightforward compared to star
formation and galaxy formation. If there is really some sort of
conflict, I would bet that it is the star-formation or galaxy-formation
stuff which is wrong, or not completely understood. People still work
on this, so obviously not all is known, whereas classical cosmology is
rather mature by now. If I recall correctly (this is not my field, but
occasionally I read about other stuff), one still doesn't have a theory
which can calculate the initial mass function of stars. If that is true
(I could try to find the reference if someone doubts this), then it is
clear that all details of star formation are not yet clear.

And if you doubt the big bang, of course, you need a theory which
explains all the other stuff the big-bang theory does.