Big Bang cosmology

Discussions ranging from space technology, near-earth and solar system missions, to efforts to understand the large-scale structure of the cosmos.

Re: Big Bang cosmology

Postby bangstrom on March 31st, 2020, 6:35 am 

BurtJordaan » March 30th, 2020, 5:06 am wrote:

I think you misunderstand what the standard model says. The CMB radiation is also perpetually "replenished", because we see farther as time goes on, bringing in continuous fresh areas of photon emission from the original recombination.

I say CMB is not replenished because it was released in a single event and is no longer being released. It is called "relic" radiation. Starlight is replenished because new stars form from the debris of old stars and starlight is continuously emitted even now. One difficulty with the CMB idea is that the radiation had to pass through a considerable amount of matter dense enough for fusion to take place without being absorbed.
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Re: Big Bang cosmology

Postby davidm on March 31st, 2020, 11:54 am 

bangstrom » March 31st, 2020, 4:35 am wrote:I say CMB is not replenished ...


This is not correct. See here.

The CMB we observe now comes from a thin shell with us in the center, and with a radius equal to the distance that the light has traveled from the Universe was 379,000 years old and until now. As time passes, we will receive CMB from a shell with an increasingly larger radius. As that light has traveled farther through space, it will, as you say, be more redshifted, or "cooler". But it will also have been emitted from more distant regions in the early Universe that, although statistically equivalent, simply will be other regions and hence look different.
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Re: Big Bang cosmology

Postby hyksos on March 31st, 2020, 6:24 pm 

What is the optical limit of today’s best telescopes either on Earth or in space. My understanding is that it is a little over 13 G light years so we can’t visualize older galaxies beyond that point. There are galaxies and more galaxies for as far as we can see up to the optical limit. Radiometric dating also has its limits.

The theory you are proposing asserts that there is no observational evidence of any astrophysical structure being older than 17 billion years. But you assert that the evidence for these older objects is conveniently just beyond the range of our telescopes. Simultaneously, you demand that people on this forum understand and appreciate your "suspicion" that the universe is far older.

The goal of science is to produce a theory that models and predicts a body of data. Your theory says that the milky way happens to accidentally sit in a pocket of the universe where all the astrophysical objects all just happen to be coincidentally young.
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Re: Big Bang cosmology

Postby curiosity on March 31st, 2020, 6:59 pm 

Re: Big Bang cosmology
Postby BurtJordaan on March 28th, 2020, 1:44 am

TheVat » 28 Mar 2020, 00:27 wrote:
Observational analysis of 1a supernovae from last year that questions dark energy as a dominant role in cosmic expansion.

I think if this analysis holds up, it may at most reduce the dominance of the dark energy (cosmological constant).
We must not forget that the CMB measurements did include these anisotropic effects and still indicate a spatially flat observable universe. To remove the cosmological constant completely will mean more than a doubling in the amount of dark matter in order to satisfy the spatial flatness.

So we may see a bit of reshuffle of the curvature parameters - but the jury is still out...


That's pretty much the way I it see too r'e the dark energy... "It cant be removed!!!"
I'm a proponent of bounce cosmology, so any speeding up of the cosmic expansion just doesn't tie in with the model I believe in. Maybe, (As I hope) the researchers have not been as diligent as need be, which would prompt a return to considering the expansion of space-time to be the sole reason for the red-shift,

Although Doppler effect and cosmological red shift, are effects of totally different phenomena... During my studies of cosmic expansion, I have been dismayed by coming across numerous cases where otherwise sane people believe the red-shift resulting from Cosmic expansion, is due to Doppler effect ??? Mixing relativistic effects caused by the speed of light, with effects caused by sub-c-motion, is a recipe for disaster, which I presume the researchers are aware of. The fiasco with the initial inaccuracies of the GPS system was a prime example of what happens when relativity isn't taken into consideration.

On a lighter note. Serendipity has lent me a helping hand with my own research. A perplexing problem I had been struggling with, was answered by something Roger Penrose said whilst talking about an unrelated problem

I just love it when unexpected gifts turn up out of the blue like that. "Happy days !!!"
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Re: Big Bang cosmology

Postby BurtJordaan on April 1st, 2020, 1:47 am 

curiosity » 01 Apr 2020, 00:59 wrote:
I'm a proponent of bounce cosmology, so any speeding up of the cosmic expansion just doesn't tie in with the model I believe in. Maybe, (As I hope) the researchers have not been as diligent as need be, which would prompt a return to considering the expansion of space-time to be the sole reason for the red-shift,

Bounce is still possible with accelerated expansion. I like Sir Roger Penrose's idea that when the matter density has been reduced to a very low value, a quantum fluctuation in a rather large volume of 'empty space' can cause it to collapse and bounce to spruce a new universe. I will have to look for a reference to the talk - it has been quite some time ago.

Although Doppler effect and cosmological red shift, are effects of totally different phenomena... During my studies of cosmic expansion, I have been dismayed by coming across numerous cases where otherwise sane people believe the red-shift resulting from Cosmic expansion, is due to Doppler effect ???

The cosmological redshift can be viewed as a large number of infinitesimal Doppler shifts between adjacent comoving observers, simply because small areas of empty space can be viewed as Minkowskian. There is much more to this statement, to which I can give you a rather mathematical reference if you want it.
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Re: Big Bang cosmology

Postby BurtJordaan on April 1st, 2020, 1:58 am 

bangstrom » 31 Mar 2020, 12:35 wrote:I say CMB is not replenished because it was released in a single event and is no longer being released.

Not as per the definition of an 'event' in physics. The CMB photons were all released more or less at the same time, not at a specific spatial location, but everywhere. The spatial region was much, much larger than the patch that we can observe today, as davidm has also referred to. We see light from a larger shell every time we look...
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Re: Big Bang cosmology

Postby bangstrom on April 1st, 2020, 3:16 am 

davidm » March 31st, 2020, 10:54 am wrote:
bangstrom » March 31st, 2020, 4:35 am wrote:I say CMB is not replenished ...

The CMB we observe now comes from a thin shell with us in the center, and with a radius equal to the distance that the light has traveled from the Universe was 379,000 years old and until now. As time passes, we will receive CMB from a shell with an increasingly larger radius. As that light has traveled farther through space, it will, as you say, be more redshifted, or "cooler". But it will also have been emitted from more distant regions in the early Universe that, although statistically equivalent, simply will be other regions and hence look different.


There appears to be some confusion about my word replenished. Recycled may be a better word.

Consider the difficulty that the CMB must have had to pass through a primal universe of atoms having a density great enough to permit the fusion of hydrogen into helium and some of the metals high up on the periodic table. That is a lot of density.

My question is, how did the CMB pass through this density of matter without being absorbed?
Last edited by bangstrom on April 1st, 2020, 3:35 am, edited 1 time in total.
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Re: Big Bang cosmology

Postby bangstrom on April 1st, 2020, 3:31 am 

BurtJordaan » April 1st, 2020, 12:58 am wrote:
The CMB photons were all released more or less at the same time, not at a specific spatial location, but everywhere. The spatial region was much, much larger than the patch that we can observe today,


No, the CMB we observe today initially had to pass through a spacial region when it was much, much smaller than what we see today and it took billions of years to reach us. That tiny region has expanded everywhere and in every direction around us since the recombination event and we are at the observational center of expansion which is where we have always been. The CMB began its journey in the early years of expansion when the entire universe was in an extremely dense state.

Do you see the density problem?
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Re: Big Bang cosmology

Postby socrat44 on April 1st, 2020, 4:32 am 

CMBR is not static, it is expanding . . . according to Big Bang
=====
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Re: Big Bang cosmology

Postby bangstrom on April 1st, 2020, 4:49 am 

socrat44 » April 1st, 2020, 3:32 am wrote:CMBR is not static, it is expanding . . . according to Big Bang
=====

That is what I am saying. Run the Big Bang movie back to the recombination epoch when the universe was 379,000 years old and the CMBR began its expansion through an incredibly dense soup of neutral hydrogen atoms.
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Re: Big Bang cosmology

Postby socrat44 on April 1st, 2020, 5:06 am 

bangstrom » April 1st, 2020, 4:49 am wrote:
socrat44 » April 1st, 2020, 3:32 am wrote:CMBR is not static, it is expanding . . . according to Big Bang
=====

That is what I am saying. Run the Big Bang movie back to the recombination epoch
when the universe was 379,000 years old and the CMBR began its expansion through
an incredibly dense soup of neutral hydrogen atoms.

. . . and the CMBR future is unknown
=====
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Re: Big Bang cosmology

Postby BurtJordaan on April 1st, 2020, 5:07 am 

bangstrom » 01 Apr 2020, 09:31 wrote:
BurtJordaan » April 1st, 2020, 12:58 am wrote:
The CMB photons were all released more or less at the same time, not at a specific spatial location, but everywhere. The spatial region was much, much larger than the patch that we can observe today,


No, the CMB we observe today initially had to pass through a spacial region when it was much, much smaller than what we see today and it took billions of years to reach us. That tiny region has expanded everywhere and in every direction around us since the recombination event and we are at the observational center of expansion which is where we have always been. The CMB began its journey in the early years of expansion when the entire universe was in an extremely dense state.

When the CMB was released, the area was not as small and dense as you seem to think. Remember that it happened 380,000 years after the BB, when our observable patch was around 80 million light years in diameter (1/1100 of today's 92 billion light years). The matter density was ~5x10-18 kg/m3, meaning each cubic meter held one billion atoms at most. Atom mass is around 10-27 kg per atom and atomic diameter is half a nano-meter at most.

Now spread that one billion atoms uniformly over that cubic meter and you will find that most of the space was empty - apart from CMB photons passing through. As the universe expanded, it got even more empty, except for some over-dense spots where the matter structures later grew...
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Reason: Corrected the diameter of the observable patch at CMB release. It had no influence on the later calculations or conclusions
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Re: Big Bang cosmology

Postby BurtJordaan on April 2nd, 2020, 3:18 am 

socrat44 » 01 Apr 2020, 11:06 wrote:That is what I am saying. Run the Big Bang movie back to the recombination epoch
when the universe was 379,000 years old and the CMBR began its expansion through
an incredibly dense soup of neutral hydrogen atoms.

That 'incredibly dense soup' was there before recombination, first quark-soup and later free electrons and protons/neutrons. After recombination, they were mainly hydrogen atoms and not very dense anymore, as I have calculated before.

At recombination, the recession rate of the limits of the observable cosmos away from the center, where we are today, was around 66c. Those picturesque visualizations are not linearly scaled and can be very misleading if taken at face value.
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Re: Big Bang cosmology

Postby bangstrom on April 2nd, 2020, 4:20 am 

I would think after recombination the density would be far greater than that for fusion to take place. Fusion normally takes a great deal both confinement and heat but, if confinement is lacking, greater heat should suffice. I will take that under consideration.
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Re: Big Bang cosmology

Postby socrat44 on April 2nd, 2020, 6:41 am 

Book: ''a universe from nothing''
---
'' Indeed, by the time the inflation ends (solving the Horizon
Problem), the curvature of the universe (if it non-zero to begin
with) gets driven to an absurdly small value so that, even today,
the universe appears essentially flat when measured accurately.
. . . But more that this, . . . the laws of quantum mechanics imply
that, on very small scales, for very short times, empty space can
appear to be boiling, bubbling, brew of virtual particles and fields
wildly fluctuating in magnitude. These '' quantum fluctuations''
may be important . . . .''
/ by Lawrence M. Krauss, page 97 /
----
So, when CMBR will come to end - the universe will be flat, but not dead.
----
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Re: Big Bang cosmology

Postby socrat44 on April 2nd, 2020, 10:33 am 

The form of the universe is depended on the cosmological constant.
1 - the cosmological constant for the universe as whole can be so small
that the universe is practically flat ( WMAP)
2 - according to quantum physics the cosmological constant
on very small scales, for very short times can increase and as
result the ''quantum fluctuations'' can appear.
3 - Dirac theorem isn't interesting in the form or size of the
universe as whole. Dirac's theory says: ''virtual particles'' exist
in the vacuum ''sea'' . . . ( no matter of form and size of vacuum ''sea'':
big, small, flat, curved, static or spiraling . . . )
4 - these small ''quantum fluctuations'' and tiny ''virtual particles''
may be important for understand the universe on larger scales.
===
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Re: Big Bang cosmology

Postby hyksos on April 2nd, 2020, 1:06 pm 

bangstrom » March 28th, 2020, 11:32 am wrote:Can you give me an example of where I deny any of the evidence?


I have already posted the following :

hyksos » March 24th, 2020, 10:25 pm wrote:
Image

That Table 4 you are looking at here looks small, punctual and simple. But every metric shown here is the results collated and cross-corroborated by several dozen orbital and ground-based telescopes over the course of 2 decades. This is the case for each age estimate listed. The tiny table masks a much more complex experimental reality.


All these estimates all mysteriously cluster around 13.7 Gyr. The mainstream consensus in science already has a theory that explains and predicts such clustering. It is called the Big Bang. The mainstream is not confused by this data. The mainstream is not surprised by this data. The mainstream is not in a state of "theoretical crisis" over this data.

These numbers are not mere educated guesses. Read any single one of the enumerated papers (they are available online) you will see how much money, time, man hours , blood, sweat and tears went into every one of these age estimations. Multiple telescope readings from multiple ground-based and low-earth orbit telescopes all cross-corroborating.


The entire body of your posts in this thread have made no attempts -- zero attempts -- at replying to , criticizing, extrapolating upon or even acknowledging the existence of this data. You are simply acting like I never posted it. No hypothesis you have put forward has made an attempt to better explain this data, or apparently even made an attempt to check itself against it. If that does not constitute "evidence denial" then what constitutes evidence denial?
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Re: Big Bang cosmology

Postby bangstrom on April 3rd, 2020, 12:55 am 

hyksos » April 2nd, 2020, 12:06 pm wrote:
bangstrom » March 28th, 2020, 11:32 am wrote:Can you give me an example of where I deny any of the evidence?


I have already posted the following :

hyksos » March 24th, 2020, 10:25 pm wrote:
Image

That Table 4 you are looking at here looks small, punctual and simple. But every metric shown here is the results collated and cross-corroborated by several dozen orbital and ground-based telescopes over the course of 2 decades. This is the case for each age estimate listed. The tiny table masks a much more complex experimental reality.


All these estimates all mysteriously cluster around 13.7 Gyr. The mainstream consensus in science already has a theory that explains and predicts such clustering. It is called the Big Bang. The mainstream is not confused by this data. The mainstream is not surprised by this data. The mainstream is not in a state of "theoretical crisis" over this data.


I saw your chart and I have seen others similar. I have also seen a few others that offer a quite different set of data based on other estimates such as the ages of star clusters. You didn’t give a source for the origin of the chart or any background information so I don’t have sufficient information to comment about it other than the following.

We have the same interpretation of the chart. As you said, “Nevertheless, they curiously, or not-so-curiously all cluster around 13.7 Gyr.” I see this interpretation as a problem. The methods used to estimate the dates trace back to the origins of things found in our contemporary universe but not expected to be found in a newly formed universe. All of the age estimates lie uncomfortably close to 13.7 BB origin or slightly older.

A simplistic interpretation of the chart is that the ages of objects in the universe are either the same age as the universe or slightly older. If all of the ages cluster around the same date as the origin of the universe, this suggests an instant creation as if by fiat and I see this as a problem.
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Re: Big Bang cosmology

Postby BurtJordaan on April 3rd, 2020, 1:32 am 

bangstrom » 02 Apr 2020, 10:20 wrote:I would think after recombination the density would be far greater than that for fusion to take place. Fusion normally takes a great deal both confinement and heat but, if confinement is lacking, greater heat should suffice. I will take that under consideration.

As I said above, the average matter density at he CMB-relarase was ~5x10-18 kg/m3, meaning each cubic meter held one billion atoms at most. The 'ripples' that we see in the CMB is 1 part in 105. The over-dense portions only much later (800 million years, after the 'dark ages') clumped those atoms gravitationally together sufficiently to ignite the first fusion driven-stars, due to local pressure.

I reckon you were originally thinking of the nucleosynthesis that happened long before the CMB were released, mere minutes after inflation ended. And as you hinted at, it was temperature, not pressure that did the job here. It is important to think about these two things (pre-CMB nucleosynthesis and gravitational collapse causing fusion) separately.
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Re: Big Bang cosmology

Postby BurtJordaan on April 3rd, 2020, 1:43 am 

bangstrom » 03 Apr 2020, 06:55 wrote:
A simplistic interpretation of the chart is that the ages of objects in the universe are either the same age as the universe or slightly older. If all of the ages cluster around the same date as the origin of the universe, this suggests an instant creation as if by fiat and I see this as a problem.

A non-simplistic interpretation says that this is what "instant creation" looked like:

Image,

from a real decent discussion: Peering toward the Cosmic Dark Ages.

Note that it does not portray the size of the universe at any point, only the chronology.
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Re: Big Bang cosmology

Postby hyksos on April 4th, 2020, 2:41 am 

bangstrom » April 3rd, 2020, 8:55 am wrote:
hyksos » April 2nd, 2020, 12:06 pm wrote:
bangstrom » March 28th, 2020, 11:32 am wrote:Can you give me an example of where I deny any of the evidence?


I have already posted the following :

hyksos » March 24th, 2020, 10:25 pm wrote:
Image

That Table 4 you are looking at here looks small, punctual and simple. But every metric shown here is the results collated and cross-corroborated by several dozen orbital and ground-based telescopes over the course of 2 decades. This is the case for each age estimate listed. The tiny table masks a much more complex experimental reality.


All these estimates all mysteriously cluster around 13.7 Gyr. The mainstream consensus in science already has a theory that explains and predicts such clustering. It is called the Big Bang. The mainstream is not confused by this data. The mainstream is not surprised by this data. The mainstream is not in a state of "theoretical crisis" over this data.


I saw your chart and I have seen others similar. I have also seen a few others that offer a quite different set of data based on other estimates such as the ages of star clusters.
.
.
.

A simplistic interpretation of the chart is that the ages of objects in the universe are either the same age as the universe or slightly older. If all of the ages cluster around the same date as the origin of the universe, this suggests an instant creation as if by fiat and I see this as a problem.


"the ages of objects in the universe are either the same age as the universe or slightly older."
Sorry about the confusion. bangstrom, you are reading this table incorrectly. What this is showing is that among the various dating techniques, the numbers given are the very oldest objects found for that particular method.

Follow this :

Radiometric dating is applied to several tens of thousands of galaxies in a survey. The oldest galaxy seen by this method is HD 115444CS, and is listed in the table. All other galaxies in the survey were aged younger than that galaxy..

Main sequence turnoff. Hundreds of thousands of stars in the main sequence are examined in a survey. The oldest is "Multiple Globular Cluster" written Multiple GCs in the table. All other clusters are young than that one.

White dwarf cooling is measured by hundreds of known dwarfs. The oldest in that survey is M 4 . All other dwarfs in the survey were younger.
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Re: Big Bang cosmology

Postby bangstrom on April 4th, 2020, 6:14 pm 

hyksos » April 4th, 2020, 1:41 am wrote:
Follow this :

Radiometric dating is applied to several tens of thousands of galaxies in a survey. The oldest galaxy seen by this method is HD 115444CS, and is listed in the table. All other galaxies in the survey were aged younger than that galaxy..

Main sequence turnoff. Hundreds of thousands of stars in the main sequence are examined in a survey. The oldest is "Multiple Globular Cluster" written Multiple GCs in the table. All other clusters are young than that one.

White dwarf cooling is measured by hundreds of known dwarfs. The oldest in that survey is M 4 . All other dwarfs in the survey were younger.

I don’t follow your logic. The study looks for the oldest representatives of each category so it should expected that all other representatives are younger? Why is this remarkable?

My observation is that the oldest representatives on the chart are the same age as, or older than, the age of the universe universe. This can be explained as experimental errors or errors of interpretation but it is poor support for the estimated age of the universe. Don’t you find it strange that anything in the universe could be older than the universe?

What is the source for your chart?
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Re: Big Bang cosmology

Postby hyksos on April 6th, 2020, 1:06 pm 

I don’t follow your logic.

There is no logic to follow here. You read a table wrongly, and I told you how to read it correctly. I apologized for the confusion because I know the table is ambiguous. It doesn't exactly say that the lefthand column is a "method" of dating. "Object" is not much of an explanation.

The study looks for the oldest representatives of each category so it should expected that all other representatives are younger? Why is this remarkable?

This table is a summary of gigantic surveys of the sky some of which took years to complete. The papers listed there have something like 80 authors.

My observation is that the oldest representatives on the chart are the same age as, or older than, the age of the universe universe. This can be explained as experimental errors or errors of interpretation but it is poor support for the estimated age of the universe. Don’t you find it strange that anything in the universe could be older than the universe?

Certainly any working cosmologist at Stanford, Oxford, MIT, et cetera would be extremely concerned over the fact that these numbers do not exactly match 13.7 Gyr. Even more unsettling for working cosmologists is the fact that the standard deviations do not overlap. Sure. This may even cause them to lose sleep. Working scientists want the measurements to match their theoretical predictions to several decimal places. They want exactitude.

You and I are not working cosmologists. For the context of this thread, which is the context of Big Bang denial, what matters it that these datasets and their estimates do not wildly contradict the consensus model of the cosmos. DO they differ from the ideal number of 13.7? Yes. I admitted such above. Given. Check. Got it.

But they are not off by an order of magnitude. We do not see globular clusters that are 93 billion years old. We do not measure galaxies that are 276 billion years old. Instead, the data shows that the very oldest galaxy is going to be at worst 16.5 billion years old. That is the generous upper bound. In the grand scheme of science and society, these numbers are excruciatingly squeezed around the theoretical predictions.

Is the current theoretical model of the universe perfect? No.

Is the current theory completely off-base? Cosmologists are extrapolating General Relativity and presuming the universe can be described as a 4-dimensional pseudo-Riemannian manifold. Its dynamics (or "evolution") are described the Einstein field equations. How do they know this? They don't know any of this. They presume it.

Is this presumption completely off-base ? Are cosmologists barking up the wrong tree?

They are not. As the observations come in, and the archives grow into databases, and as the databases grow into terabytes, that data is agreeing with the theory.

What is the source for your chart?

It's you're lucky day. I'm going to give you a full bibliography.

Before you dig into this material : "M4" is shorthand for globular cluster Messier 4. https://en.wikipedia.org/wiki/Messier_4


r-Process Abundances and Chronometers in Metal-poor Stars
John J. Cowan, B. Pfeiffer, K.-L. Kratz, F.-K. Thielemann, Christopher Sneden, Scott Burles, David Tytler, and Timothy C. Beers
The Astrophysical Journal, Volume 521, Number 1

The r-Process in the Neutrino Winds of Core-Collapse Supernovae and U-Th Cosmochronology
Shinya Wanajo and Naoki Itoh
Department of Physics, Sophia University
Yuhri Ishimaru Institut d'Astrophysique de Paris,
Satoshi Nozawa Josai Junior College for Women,
and
Timothy C. Beers Department of Physics and Astronomy, Michigan State University
Received 2002 February 20; accepted 2002 June 8
The Astrophysical Journal, 577:853-865, 2002 October 1

Distances, Ages, and Epoch of Formation of Globular Clusters
Eugenio Carretta and Raffaele G. Gratton Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5,
and
Gisella Clementini and Flavio Fusi Pecci
Osservatorio Astronomico di Bologna,
Received 1999 February 3; accepted 1999 November 30
The Astrophysical Journal, 533:215-235, 2000 April 10

Theoretical Uncertainties in the Subgiant Mass-Age Relation and the Absolute Age of ω Centauri
Brian Chaboyer and Lawrence M. Krauss
Published 12 February 2002 • © 2002. The American Astronomical Society. All rights reserved. Printed in U.S.A. The Astrophysical Journal Letters, Volume 567, Number 1



Hubble Space Telescope observations of the white dwarf cooling sequence of M4
Brad M. S. Hansen,Harvey B. Richer,Greg. G. Fahlman,Peter B. Stetson, James Brewer, Thayne Currie, Brad K. Gibson, Rodrigo Ibata, R. Michael Rich, and Michael M. Shara
Received 2004 January 27; accepted 2004 July 3

The Astrophysical Journal Supplement Series, 155:551–576, 2004 December
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Re: Big Bang cosmology

Postby Hendrick Laursen on April 10th, 2020, 6:00 am 

I guess Popper was kinda incorrectly quoted here. According to Popper "falsifiability" is a defining feature of scientist theory, which is to say, if you can't possibly falsify a scientific theory, it's most probably not science.
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Re: Big Bang cosmology

Postby hyksos on April 18th, 2020, 2:08 pm 

Hendrick Laursen » April 10th, 2020, 2:00 pm wrote:I guess Popper was kinda incorrectly quoted here. According to Popper "falsifiability" is a defining feature of scientist theory, which is to say, if you can't possibly falsify a scientific theory, it's most probably not science.

Ignoring a giant body of evidence, or feeling one has no responsibility to consider what is measured... whatever that method is, it is not science.
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Re: Big Bang cosmology

Postby bangstrom on April 18th, 2020, 7:39 pm 

hyksos » April 18th, 2020, 1:08 pm wrote:
Ignoring a giant body of evidence, or feeling one has no responsibility to consider what is measured... whatever that method is, it is not science.


The problem is knowing where to draw the fine line between what is observed and what is speculation about what is observed. One specific problem, among several, with the ages of the astronomical objects in the chart is that the ages have been shortened by the use of the Lambda-CDM Model.

Dark matter, dark energy, and accelerated expansion are speculations made about what is directly observed. They are not observations in themselves and they not a difficulty for most models outside the BBT. The use of the Lambda-CDM Model is the application of fudge factors to make the theory fit the observations rather than examining the basic assumptions made within the BBT itself.

Ignoring what is being measured is not the same as ignoring what we think is being measured because the latter is likely to be wrong if the two are in conflict. So go with the evidence and not the theory. I think this is what you are saying but I don't trust evidence that has been "cooked" to fit the theory.
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Re: Big Bang cosmology

Postby hyksos on April 19th, 2020, 6:52 pm 

bangstrom » April 19th, 2020, 3:39 am wrote:The use of the Lambda-CDM Model is the application of fudge factors to make the theory fit the observations rather than examining the basic assumptions made within the BBT itself.

I both went over this -- and I have already replied to it. But if you like we can start going in circles.

The basic assumptions are being Unexamined? The basic assumptions are lain bare in an honest, open and forthright way.

1. MOND
Alternative theories that gravity is maybe not quite right on large scales are known, documented, talked about, written about, debated, even even compared against measurements. The idea that that dark matter doesn't exist and gravity must be modified for tiny accelerations (Modified Newtonian Dynamics =MOND) is not fitting the data, now that some 20+ galaxies have been identified that do not have dark matter. If galaxy rotation curves are due to a fundamental law of physics, the existence of galaxies which violate the law would be impossible. Woopsie, there are now 26 of them on record.

2. GR is wrong
The current consensus model is that General Relativity is the right model for the entire universe. Do cosmologists know this? They do not. They assume it. What do you do next? You measure the sky, and compare those observations against the assumptions. Are they matching? They are. ( I already wrote this above. You ignored it. Now I'm writing it again. )


I think this is what you are saying but I don't trust evidence that has been "cooked" to fit the theory.

I implore you, bangstrom,.. implore you to go and engage with telescope data on the aging methods of globular clusters. Learn to read the temperature/luminosity scatterplots. Hell, go ahead and download the data in CSV format and graph them yourself in excel.

I am perfectly confident in stating the following : You will find that nothing about the this data is being "cooked" to "fit a theory". These measurements do not even rely on an interpretation of decay rates of radioactive elements.

On a personal note, I am schooled in the school of Big Bang denial. I've heard every argument made by every denier and read all the blogs and even biographies of Fred Hoyle line my shelf. What changed my mind?

Globular cluster data.

It broke my camel's back. After learning how to read this data, I came to realize that the structures around us in the sky have an age -- indeed -- a cut-off point in their ages. If there were older ones, we would absolutely see them and easily so. (Hell, they should already be archived.) We do not see them.

One might complain that we cannot rely on a single datapoint or single method. Correct. That's good skepticism. Luckily other techniques of aging are used and those estimates more-or-less agree with G.C. data. We have corroboration. If you are doing science, then you are obligated to address these corroborations, not dismiss them offhand.
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Re: Big Bang cosmology

Postby bangstrom on April 21st, 2020, 2:51 am 

hyksos » April 19th, 2020, 5:52 pm wrote:
I both went over this -- and I have already replied to it. But if you like we can start going in circles.

The basic assumptions are being Unexamined? The basic assumptions are lain bare in an honest, open and forthright way.

The basic assumptions are not being examined to keep up with new observations. That is my complaint. The problem is that over time assumptions tend to become “facts” even when no longer supported by observations. I find it necessary to distinguish between observations and assumptions with the greatest amount of credence being placed on observations.

One basic assumption that has long been suspect, even by Hubble himself, is that galactic redshifts are reliable indicators of recessional velocities or even if they are recessional velocities and not something entirely different. The interpretation of galactic redshifts as recessional velocities was once the most intuitive explanation but it seems like an artifact of an earlier time when the galaxies were commonly thought of as ejecta from some giant explosion expanding into pre-existing space.

hyksos » April 19th, 2020, 5:52 pm wrote:
1. MOND
Alternative theories that gravity is maybe not quite right on large scales are known, documented, talked about, written about, debated, even even compared against measurements. The idea that that dark matter doesn't exist and gravity must be modified for tiny accelerations (Modified Newtonian Dynamics =MOND) is not fitting the data, now that some 20+ galaxies have been identified that do not have dark matter. If galaxy rotation curves are due to a fundamental law of physics, the existence of galaxies which violate the law would be impossible. Woopsie, there are now 26 of them on record.


This isn’t clear. What law of gravity is being violated? Is it some classical law, GR, MOND? And of the 26 galaxies without dark matter, are you saying they are anomalies or the same condition we should expect of other galaxies?

hyksos » April 19th, 2020, 5:52 pm wrote:
2. GR is wrong
The current consensus model is that General Relativity is the right model for the entire universe. Do cosmologists know this? They do not. They assume it. What do you do next? You measure the sky, and compare those observations against the assumptions. Are they matching? They are. ( I already wrote this above. You ignored it. Now I'm writing it again. )


I replied earlier that observations don’t match the assumptions or GR which predicts a universe with a slowing expansion rate. If they matched there would be no need for the various patches such as Guth’s inflation, dark matter, dark energy, or the lambda factor.
I am not ignoring what you say. I just don’t find it convincing. I have looked over much of the same evidence and found it either lacking or better explained outside the BB box.

hyksos » April 19th, 2020, 5:52 pm wrote:
I implore you, bangstrom,.. implore you to go and engage with telescope data on the aging methods of globular clusters. Learn to read the temperature/luminosity scatterplots. Hell, go ahead and download the data in CSV format and graph them yourself in excel.

I am perfectly confident in stating the following : You will find that nothing about the this data is being "cooked" to "fit a theory". These measurements do not even rely on an interpretation of decay rates of radioactive elements.

In the seventies the Allan Sandage team of astronomers was discovering globular clusters in excess of 20G years when the universe was thought to be no older than 15G years. Later the Sandage data was reviewed and negotiated down to barely fit within 15G year estimate with most outliers on the older side.

This prompted Edward Harrison to try plugging in different density values into the Friedman equation and he found that a universe of greater density and several times older and larger than 15G years fit all observed parameters without modification.
Later when the age of the universe was adjusted downward to 13.8G years the cluster data was boiled down a bit more with the lambda-CDM to fit the estimated younger age.
This is why I say the data looks “cooked.”

Harrison’s calculations of a larger, older universe seem perfectly plausible to me and consistent with observations. The total flatness of the universe suggests a universe that is either not expanding or one that is much older than indicated by the Hubble constant. The Hubble constant is only as reliable as the assumption that galactic redshifts equate to true recessional velocities.

hyksos » April 19th, 2020, 5:52 pm wrote:
Globular cluster data.

It broke my camel's back.

What broke my camel’s back was the BOOMERANG observation that the expansion of the universe was accelerating. I have long had my suspicions that there is more to galactic redshifts than simple recessional velocities. The redshifts are indicators of global change that may not even be recessional.

An accelerated expansion of the universe violates laws of physics and all previous predictions of either non-expansion or a slowing expansion. Even worse, is the ad hoc assumption of dark energy and the implication that 96 percent of the universe consists of something unknown and unexplainable. This is a bridge too far.

hyksos » April 19th, 2020, 5:52 pm wrote:
If you are doing science, then you are obligated to address these corroborations, not dismiss them offhand.

What I don’t dismiss offhand are corroborations that examine the same data using the same science- GR included- but drawn from a different point of view rather than looking at a single model to the exclusion of all others. This is a much less forgiving method of examination because you have other models for comparison and the BBT often doesn’t fare well when compared with other possible explanations.
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Re: Big Bang cosmology

Postby hyksos on April 21st, 2020, 4:54 am 

bangstrom,

As I already said earlier (which is ignored and now I'm writing it again). The professional cosmologists at Oxford get very upset over deviations of 2% , and 4% makes them very nervous. They want their models to match observations right on the head every time. In their isolated cloisters, they even go as far as to say a 4% deviation is a "crisis in cosmology". That's overweening academia.

Everything in your post is about percentage differences -- which I fully admit are very important for the working cosmologist who wants to publish. Admittedly so. You are getting into details about ages of 15 versus 20. But that's not the point of this thread at all. These are distractions and useless details.

The observational data is in. The data shows that the universe has a finite age. That's what matters here, in this thread. You can slice the cake however, but when I say "Big Bang" I mean the evidence of a finite age. A finite age means there was a beginning. That beginning (I make no commitments of its nature) was the Big Bang. It's that simple.

(marginal sidebars like singularities, Hawking, beginnings of time. Those are speculatory sidebars. I will bring them up or I won't. There is no commitment)

I am not here to adjudicate accelerated expansion versus slowing expansion versus constant expansion. My posts do not contain any talk of any of those things. All nice topics. YOu can make a new thread at your leisure. This thread is about Big Bang denial. The topical laserpointer won't be moved.


I replied earlier that observations don’t match the assumptions or GR which predicts a universe with a slowing expansion rate. If they matched there would be no need for the various patches such as Guth’s inflation, dark matter, dark energy, or the lambda factor

I'm not Alan Guth. I'm not a spokeperson for Alan Guth, and you will not be debating him through me as a proxy. You tried this already in this thread, and I didn't take your bait. I'm not taking it now.

I am not ignoring what you say. I just don’t find it convincing.

You are ignoring what I say. I am repeating myself. Anyone reading this thread can see this happening.

An accelerated expansion of the universe violates laws of physics and all previous predictions of either non-expansion or a slowing expansion. Even worse, is the ad hoc assumption of dark energy and the implication that 96 percent of the universe consists of something unknown and unexplainable. This is a bridge too far.

This looks like an admission that the acceleration is real. You seem wholly convinced that accelerated expansion has been definitively observed. That would entail that you believe metric expansion is happening. Metric expansion of spacetime is one of the hallmark predictions of General Relativity. But wait , that would mean that GR is a correct description of the universe, right? What am I missing?


This isn’t clear. What law of gravity is being violated? Is it some classical law, GR, MOND? And of the 26 galaxies without dark matter, are you saying they are anomalies or the same condition we should expect of other galaxies?

It's perfectly clear. Lets not dance around this bonfire. Do you deny the existence of dark matter? Yes or no?
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Re: Big Bang cosmology

Postby Hendrick Laursen on April 23rd, 2020, 11:00 pm 

hyksos » April 18th, 2020, 8:08 am wrote:
Hendrick Laursen » April 10th, 2020, 2:00 pm wrote:I guess Popper was kinda incorrectly quoted here. According to Popper "falsifiability" is a defining feature of scientist theory, which is to say, if you can't possibly falsify a scientific theory, it's most probably not science.

Ignoring a giant body of evidence, or feeling one has no responsibility to consider what is measured... whatever that method is, it is not science.


Can it be improved? Can it be false? Can it be refuted and be replaced with something else? If the answer to these questions is not yes we're not dealing with science.
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