Early Galaxy Evolution (High-z Metallicity)

[modest]

Hello All

As far as I know the formation of Fe is within the solar envelope. It would take 10 Gyrs for a normal star such as ours to go nova and release the Fe

 

It also might be helpful to note that our sun will never make iron. It isn't massive enough.

 

-modest

[coldcreation]

Do you not feel, coldcreation, that this could at best be described as rather sloppy research and places the rest of your arguments into a questionable light?

 

Sloppy, yes I was. I should not have placed those references next to the sentence in question. Though some of my other references point in the direction I was headed. There was a certain risk-taking involved, and I am prepared to go further in that direction, if observations continue to show old stellar populations, high-metallicity at very large redshift. So, no, I do not simply adapt a wait and see method.

 

Despite the apparent inability at the present time to resolve these conflicting views - one of high-metallicity of deep-space objects (meaning that galaxies appear very similar to local galaxies), and the other, of rapid evolution in the look-back time (where metal-rich objects are located where there should be none, or few objects at all) - modern cosmology has tended to pursue one strategy first - thus limiting the scope of possibilities, or interpretations.

 

But the detection of high-z heavy-metal objects reminds us that cosmology remains an open field and draws attention to a further uncertainty regarding the standard model. That can only be good news since, even if it turns out to be correct, placing it in check from time to time will serve to increase its credibility.

 

However if it turns out to be erroneous, the opposition will have served an important purpose too: that of furthering our understanding of the physical universe and how it evolves with time.

 

What risks (theoretically speaking) are cosmologists prepared to take in order to achieve modest, even marginal, objectives? While the central target, like that of all fields of science where standard models are the norm, is self-preservation, their secondary goal should be to consider alternative possibilities based on interpretations that may lead to increasing risks with respect to standard model viability (or, rather, untenability).

 

Ultimately, this risk-taking (as was the rule for Hoyle, Arp, Narlikar and others in the opposition camp) will lead to further insight to the workings of nature (in the global sense, or universal sense). The risk-taking dilemma is the most important and challenging issue for both the mainstream and their adversary (for both current and future interpretations of observational data).

 

 

CC

[Eclogite]

Sloppy, yes I was. I should not have placed those references next to the sentence in question. Though some of my other references point in the direction I was headed.

Thank you for that concession. I share with you, I believe, serious reservations about the reality of the Big Bang. I am keen to see evidence that questions the current viewpoint. However, since this is counter to the accepted - and quite solidly validated - theory, I think it is necessary to be more precise and more careful than normal in presenting and evaluating such evidence. It was this concern that prompted me to question your references as I did.

[coldcreation]

Thank you for that concession. I share with you, I believe, serious reservations about the reality of the Big Bang. I am keen to see evidence that questions the current viewpoint. However, since this is counter to the accepted - and quite solidly validated - theory, I think it is necessary to be more precise and more careful than normal in presenting and evaluating such evidence. It was this concern that prompted me to question your references as I did.

 

Sure. No problem.

 

Note the the data available at this time is not conclusive for either the BBT or any other theory.

 

 

The contrasting world-views presented above highlight our difficulties in deciding what the universe is up to, and in formulating a tenable model to deal with it. The fundamental query remains: despite the uncertainty concerning the standard model, can current observational data be brought into a constructive partnership with a viable alternative solution, committed to reducing the conflict between theory and observational evidence within a consistent framework?

 

Certainly it is worth the effort. None should waver in his or her determination to maintain a formidable strategy aimed directly at determining metallicity at high-redshift, since it is their where the incoming data will make or break competing models.

 

While that effort is underway at this time, it is evident that this is just the tip of the iceberg.

 

 

CC

[Pluto]

Hello Modest

 

You said

 

It also might be helpful to note that our sun will never make iron. It isn't massive enough.

 

 

Mate I do not know where you get the info from.

 

But! google for the sun properties.

[modest]

Hello Modest

You said

It also might be helpful to note that our sun will never make iron. It isn't massive enough.

 

Mate I do not know where you get the info from.

 

But! google for the sun properties.

 

Then it was a useful thing to mention.

 

Here is the sun's main fusion cycle:

 

 

As you can see, it doesn't fuse elements into iron.

 

Here is what's called the CNO or Carbon-Nitrogen-Oxygen main and secondary cycle. This is not the pp fusion chain! This cycle feeds on elements already present when the star formed, here it is:

 

 

This CNO cycle is responsible for 2% of the sun's fusion and involves the heaviest fusion elements. As you can see, the heaviest element created is fluorine which quickly returns to oxygen. I got these from this site: Solar Fusion & Neutrinos and here is a quote:

 

This completes the picture of nuclear fusion in the sun. As the sun ages it will gain a hotter core, and eventually begin fusing helium into carbon, once the temperature reaches about 10^8 Kelvins. At those higher temperatures, the CNO cycle will also become more important. The sun is not massive enough to go beyond the stage of fusing helium into carbon (and a little oxygen perhaps). It will eventually pass through the stage of Red Giant, followed by planetary nebula, and quietly fade away as a carbon white dwarf. More massive stars will, depending on their mass, fuse heavier nuclei, all the way to iron, which requires central temperatures as high as 3,000,000,000 Kelvins. The most massive stars, those with masses in excess of about 8 to 10 solar masses, will be unable to produce a stable core at all in the normal course of the fusion cycles. Those stars will end as supernova explosions, leaving behind a neutron star or black hole.

 

So, our sun doesn't make iron, it isn't massive enough. Both the main fusion cycle and the CNO cycle stop short of iron. The iron in our sun came from other, more massive, stars.

 

Is this ok?

 

-modest

[coldcreation]

.

 

 

 

In this press release: Old Galaxies in the Young Universe

Very Large Telescope Unravels New Population of Very Old Massive Galaxies it is written...

 

The galaxies appear to have masses in excess of one hundred thousand million solar masses and they are therefore of sizes similar to the most massive galaxies in the present-day Universe. Complementary images taken within the GOODS ("The Great Observatories Origins Deep Survey") survey by the Hubble Space Telescope show that these galaxies have structures and shapes more or less identical to those of the present-day massive elliptical galaxies.

 

The new observations have therefore revealed a new population of very old and massive galaxies.

 

The existence of such massive and old spheroidal galaxies in the early Universe shows that the assembly of the present-day massive elliptical galaxies started much earlier and was much faster than predicted by the hierarchical merging theory. Says Andrea Cimatti (INAF' date=' Firenze, Italy), leader of the team: "Our new study now raises fundamental questions about our understanding and knowledge of the processes that regulated the genesis and the evolutionary history of the Universe and its structures."[/quote']

 

See the original paper here: Old Galaxies in the Young Universe. Here as some words from that paper:

 

In the local universe' date=' over half of all stars are found in massive spheroidal galaxies characterized by old stellar populations and absent or weak star formation. In current galaxy formation scenarios, such early-type galaxies appear rather late as the culmination of a hierarchical merging process. However, observations have not yet established how and when such systems formed, and if their seemingly sudden appearance when the universe was about half its present age (z ? 1) results from a real evolutionary effect or from the observational difficulty of identifying them at earlier epochs.

 

Here we report the spectroscopic and morphological identification of four old, fully assembled massive (> 10^11 solar masses) spheroidal galaxies at 1.6 < z < 1.9, the farthest such objects currently known. The existence of such systems when the universe was only ? 1/4 its present age, shows that the build-up of massive early-type galaxies was much faster in the early universe than so far expected from theoretical simulations

 

 

It is generally thought that the so-called “redshift desert” (i.e. around 1.4 < z < 2.5) represents the cosmic epoch when most star formation activity and galaxy mass assembly took place. Our results show that, in addition to actively star forming galaxies, also a substantial number of “fossil” systems already populate this redshift range, and hence remain undetected in surveys biased towards star-forming systems.

 

The luminous star-forming galaxies found at z > 2 in sub-mm and near-infrared surveys may represent the progenitors of these old and massive systems[/quote']

 

 

And in this work: Galaxy Clustering at z ~ 3, in section 3, it is written: "...it was somewhat surprising to encounter significant "spikes" in the redshift distribution at z ~ 3, where naively one might expect clustering to be significantly weaker than at z < 1 under any structure formation scenario that involves gravitational instability."

See also section 4. My interpretation of the data is that large-scale structures at high-z are very similar to those observed locally. It seems that galaxy clustering at high redshift is not confirming unambiguously the standard model: an apparent disappointment to the authors of the paper.

 

 

CC

[modest]

From NewScientistTech

referencing Astronomy & Astrophysics (vol 416, p L35):

A small, faint galaxy may claim the title of the most distant object known - breaking a record that was set just two weeks ago.

The new find appears to lie 13.2 billion light-years away from Earth and reveals what the earliest galaxies looked like.

Light from this galaxy may have formed a mere 460 million years after the Big Bang, which formed the Universe 13.7 billion years ago, say its discoverers.

The previous record-holder, reported in February 2004, dates back to 750 million years after the birth of the Universe...

 

Named Abell 1835 IR1916, the new galaxy appears to form stars at the rate of between one and five suns per year and contains ten thousand times less matter than our Milky Way. Such small, star-forming galaxies are expected in the early Universe as they are thought to be the building blocks of the large galaxies seen today.

 

So, what kind of stars were being made in this galaxy 13.2 Gyrs ago?:

 

DISCOVERY OF HE 1523−0901, A STRONGLY R-PROCESS ENHANCED METAL-POOR STAR WITH

DETECTED URANIUM

is the discovery of the oldest uranium dated star. It has the exact age as our distance estimated for our oldest galaxy above - 13.2 billion years. The star is a great indication of what the universe was like 460 million years after the Big Bang. The star putts an independently measured lower limit on the age of the universe as well.

1523−0901 and CS 31082-001 are in good agreement with the WMAP result of 13.7Gyr for the age of the Universe

 

Wouldn't it be something crazy if a star was uranium dated to something like 30 or 40 billion years

[coldcreation]

Wouldn't it be something crazy if a star was uranium dated to something like 30 or 40 billion years :)

 

 

 

Stars have been found in globular clusters to be up to 18 Gyr old:

 

How Old is the Universe?

 

The oldest globular clusters contain only stars less massive than 0.7 solar masses. These low mass stars are much dimmer than the Sun. This observation suggests that the oldest globular clusters are between 11 and 18 billion years old. The uncertainty in this estimate is due to the difficulty in determining the exact distance to a globular cluster (hence' date=' an uncertainty in the brightness (and mass) of the stars in the cluster). Another source of uncertainty in this estimate lies in our ignorance of some of the finer details of stellar evolution. Presumably, the universe itself is at least as old as the oldest globular clusters that reside in it.[/quote']

 

 

And check this out: Globular clusters, Hipparcos, and the age of the galaxy

 

 

Given accurate distance estimates, matching those data against the predictions of theoretical models allows one to estimate the age of the cluster from the luminosity (mass) at the main-sequence turnoff. The most extreme metal-poor clusters generally are also found to be the oldest, weighing in at ages of 16–22 Gyr. The uncertainties in those ages, which are a result of uncertainties in the underlying stellar physics, were estimated as only ?15% (3). Thus, T0, the age of the universe, can be deduced as being at least 17 Gyr.

 

This too may be only the tip of the iceberg.

 

 

 

 

Something has only just begun.

 

 

 

 

CC

[coldcreation]

Thank you for that concession. I share with you, I believe, serious reservations about the reality of the Big Bang. I am keen to see evidence that questions the current viewpoint. However, since this is counter to the accepted - and quite solidly validated - theory, I think it is necessary to be more precise and more careful than normal in presenting and evaluating such evidence. It was this concern that prompted me to question your references as I did.

 

 

Only with the injunction of exotic dark energy and nonbaryonic dark matter (96% of the mass-energy density) is the BBT "validated."

 

 

But we shouldn't count on miracles to solve the age problem.

 

 

You name the problem in astrophysics, and a scientist somewhere will be working on a technical solution. But the problem with determining the ages of stars is not solely a technical one that can be remedied technologically.

 

 

It is a political problem.

 

 

When new observational data comes in (regarding not only the age of stars in the Milky Way Galaxy, but, too, those confined in the abyssal depths of the universe), it is very unlikely that the data will be part of the solution - on the contrary, just another part of the problem.

 

 

 

CC

[modest]

Wouldn't it be something crazy if a star was uranium dated to something like 30 or 40 billion years

 

Stars have been found in globular clusters to be up to 18 Gyr old:

 

I followed your first link. It says:

 

The expansion age measured by WMAP is larger than the oldest globular clusters, so the Big Bang theory has passed an important test. If the expansion age measured by WMAP had been smaller than the oldest globular clusters, then there would have been something fundamentally wrong about either the Big Bang theory or the theory of stellar evolution. Either way, astronomers would have needed to rethink many of their cherished ideas. But our current estimate of age fits well with what we know from other kinds of measurements: the Universe is about 13.7 billion years old!

 

I don’t know why you referenced this webpage. It is current and disproves your claim explicitly and completely - odd.

 

I follow your second link:

 

Given accurate distance estimates, matching those data against the predictions of theoretical models allows one to estimate the age of the cluster from the luminosity (mass) at the main-sequence turnoff. The most extreme metal-poor clusters generally are also found to be the oldest, weighing in at ages of 16–22 Gyr. The uncertainties in those ages, which are a result of uncertainties in the underlying stellar physics, were estimated as only ?15% (3). Thus, T0, the age of the universe, can be deduced as being at least 17 Gyr.

 

So, the first thing I notice, it was written 10 years ago. You and I both know what mistakes were made involving distance and age calculations with globular clusters in the 90’s. But, I will set that aside and read what you’ve referenced.

 

It is as you quote above and goes on to say:

 

This lower limit is in stark contrast to cosmological estimates, based on the most recent determinations of the large-scale Hubble expansion.

 

As I expect and as you portray.

 

Even the lower values of H0=50–55 km•s^-1 Mpc^-1 favored by Sandage et al. (5) can scarcely accommodate a 12-Gyr-old, critical-density universe.

 

The info’s out of date, but it is as you represent. Then I read the next paragraph:

 

The crucial point, however, emphasized by Sandage (6), is that the accuracy of the cluster ages depends crucially on the accuracy of the cluster distances. The turnoff mass in globular clusters is close to 1 M⊙, where a small change in mass (luminosity) represents a change in the main-sequence lifetime of 1+Gyr. As we shall describe, the availability of new, high-accuracy trigonometric parallax measurements for a larger sample of nearby halo subdwarfs has permitted a critical reevaluation of the cluster-distance scale. When the recalibrated cluster color-magnitude diagrams are combined with the latest stellar models, it becomes clear that the data are compatible with ages that are significantly younger than had been the norm. Although the age paradox does not vanish utterly, the discrepancy is reduced to a matter of no more than 1 Gyr.

 

Did you read this? This paper is written after or perhaps as the new geometric distance data was done. It, in fact, counters your point again. You should have found a paper perhaps 2 years older and it would be ignorant of the discrepancy and appear problematic for the standard model as you suggest.

 

As your links tell us, there is no problem with stellar ages in globular clusters vs. the standard model. They support one another. This is well-known. Also, there is a more-direct way to determine the age of the oldest stars with less uncertainty and less variables. See my post above.

 

-modest

[coldcreation]

.

 

 

 

In this article, Is the Universe Younger than its Oldest Stars?, it is written:

 

In 1994 globular cluster stars were generally accepted as the oldest stars we can see' date=' but that is no longer the case. The last couple of years has seen an attempt to derive the ages of old metal-poor galactic halo stars (see for instance, "r-process abundances and chronometers in metal-poor stars" by J.J. Cowan et al., Astrophysical Journal 521(1): 194-205, Part 1, August 10 1999). The few reported ages are in the 15 billion year range; the cited paper by Cowan et al. gives 15.6±4.6 billion years, which covers the rather expansive range of 11.0 billion to 20.2 billion years. The range of ages allowed by the HST Key Project results falls just short of 15 billion, but the majority of the bottom half of the uncertainty range cited by Cowan et al. falls within the Key Project range. So even if we include the halo stars, there is still no major conflict between the cosmological and astrophysical ages for the universe. And if the accepted value of H0 should move downward (as Sandage & Tammann and others would have it), the older halo stars are even easier to accomodate. But the argument over H0 remains on the table.

 

The bottom line is that there is not now a conflict between the astrophysically determined ages of the oldest stars, and the cosmologically determined age of the universe. While there was one in 1994 it was predictably short lived. While it made good reading for the popular press, astronomers were already busy trying to find the right solution. The result was that the cosmological age moved up (as H0 moved down), through the addition of more and better data, and the astrophysical ages moved down, through the addition of more precise techniques and more detailed models. In short, we learned more about the problem, and exercised that knowledge to reach a new conclusion. But I think it is safe to say that the universe is definitely not less than 10 billion years old, and definitely not more than 20 billion years old, if the expanding universe and big bang cosmology is correct.[/quote']

 

 

Here is the original paper: R-Process Abundances and Chronometers in Metal-Poor Stars" by J.J. Cowan (et al)

 

Comparing with the theoretical ratio suggests an average age of these two very metal poor stars to be approximately 15.6 +/- 4.6 Gyr' date=' consistent with earlier radioactive age estimates and recent globular and cosmological age estimates.[/quote']

 

 

That gives the age of stars between 11 and 20.2 billion years old.

 

 

 

 

CC

[modest]

That gives the age of stars between 11 and 20.2 billion years old.

CC

 

Very nice.

 

Also, those same stars were looked at again (1) in 2001 with improved Th/U dating giving a lower limit of 10 to 11 Gyrs.

 

It seems clear that our best data about the age of the universe is closely supported by many independent methods of calculation and the better our accuracy in measurement - the better supported it is.

 

-modest

[coldcreation]

Very nice.

 

Also, those same stars were looked at again (1) in 2001 with improved Th/U dating giving a lower limit of 10 to 11 Gyrs.

 

It seems clear that our best data about the age of the universe is closely supported by many independent methods of calculation and the better our accuracy in measurement - the better supported it is.

 

-modest

 

Recall that 10 years ago it was thought the universe was 15 Gyr old. Then after the SNe Ia data came in, the age of the universe had to be revised downward, to 13.7 Gyr.

 

That, of course revivified the age crisis. It was previously thought globular clusters were around 14 - 20 Gyr old (some estimates were closer to 20 - 30 Gyr) - an age crisis in itself at the time, but nothing in comparison with a 13.7 Gyr cosmos.

 

So it became clear (politically) that something had to be done (quantitatively) to lower the age of stars (dramatically).

 

In other words, what you call improved Th/U methods of dating is really just producing figures that are more acceptable politically.

 

 

 

 

CC

[Mike C]

The problem is that technology has caught up with the standard model for galaxy evolution, and telescope resolution has now reached the point that exceedingly distant and massive objects are observed to contain high metallicity. We have seen this problem looming for nearly twenty years but until recently have been unable to verify the extent to which observations of deep space objects could meet the requirements for survivability of the standard model.

 

Efforts to develop a full understanding of galaxy formation have been embodied the Hubble Ultra Deep Field program. Results have not offered clear evidence for hierarchical evolution of galaxies from fragmentary star clusters to pathological colliding galaxies, to full spirals and ellipticals. The strongest direct visual evidence to determine cosmological evolution consistent with the hot big bang/cold dark matter cosmology where the universe expands from a hot dense state has not been forthcoming. So the idea that matter cools and coagulates and triggers the onset of star formation shortly after an epoch called the "dark ages" or "redshift desert" has run into serious trouble. Scientists would have been delighted if observational evidence had been found consistent within this framework, but new surprises on observational fronts have surfaced that challenge theory.

 

 

Simply put, and pending further (I still have to study the latest findings) investigation, the supposition that the morphology of galaxies in the Hubble Deep Fields is very different in the past than in the present is not a confirmed observational fact, when redshift and surface brightness are taken into account.

 

 

Efforts to develop a new model of galaxy formation are embodied in the idea that stars formed much earlier than previously thought, and so too galaxies (that was already a problem post-1998 SNe Ia data). In effect, observations that show metal-rich massive objects thriving during the supposed "dark ages" are not easily absorbed into the mainstream world view..Snip.

 

Thanks CC for this information that adds to all the other evidence that refutes the BBU.

 

The BB'ers cannot even answer a simple question like -

What is driving the 'expansion of space'?

 

Mike C

[Pluto]

Hello All

 

Hello CC and MC

 

For 40 yrs I have been discussing the Big Bang and its lack of logic and evidence and that the theory was based on ad hoc ideas supported on very weak foundations.

 

and yet,,,,,,,,,,,,,,,it did become the standard model supported by politics, churches and school systems, Oh!!!!!!!!!!! yes AND lots of money.

 

Most links on the net refer to the BB as an event, that did happen and proceed to explain and support the theory.

[coldcreation]

Very nice.

 

Also, those same stars were looked at again (1) in 2001 with improved Th/U dating giving a lower limit of 10 to 11 Gyrs.

 

It seems clear that our best data about the age of the universe is closely supported by many independent methods of calculation and the better our accuracy in measurement - the better supported it is.

 

-modest

 

You mention the lower limit of 11 Gyr, but say nothing of the upper limit.

 

It seems, from the paper you link, that the new and inproved Th/Eu dating gives an average chronometric age for at least two well known stars of 15.6 Gyr plus or minus 4.6 Gyrs. That is between 11 Gyr and 20.2 Gyr.

 

Obviously the upper limit is in gross violation of the estimated 13.7 Gyr old universe (according to the standard model; Lambda-CDM).

 

But even if we take the 15.6 Gyr at face value we still have a large problem. Perhaps more dark matter and dark energy will solve the problem (99% of the combined mass-energy density, as opposed to 96%, currently favored), but I doubt it.

 

It doesn't seem clear that "our best data about the age of the universe is closely supported by many independent methods of calculation" from the paper you link.

.

 

 

What gives?

 

 

 

CC