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Author Topic:   Cosmological Constant and Dark Energy has been in the news for months.
LamarkNewAge
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Posts: 2497
Joined: 12-22-2015


Message 1 of 53 (917477)
04-09-2024 12:52 AM


But the last week, it has been reported widely.
The largest survey of the sky, reported back in January, showed that there was probably only a 5% chance Dark Energy had the numbers that matched up with a supposed value of the "Cosmological Constant".
I always preferred a 100% flat universe, as it was seen as the most consistent cosmological topography which was consistent with the Many Worlds Theory.
But I doubted the Dark Energy was very good proof of the perfect "cosmological constant".
I dont feel a 100% flat universe is needed for the Many Worlds Theory to be possible.
(Copenhagen is still about to get buried overnight, when psychic studies are finally released
The relevant study, released in January (But the developing results have been leaked for years).
quote:
Will We Ever Know the True Nature of Dark Energy? | NOVA | PBS
Astronomers discovered dark energy in 1998, but are we any closer to understanding what it really is?
MONDAY, JANUARY 27, 2014 THE NATURE OF REALITY
....
Future observations should help narrow down the possibilities. Dark energy’s behavior over time, which is measured by the ratio of its pressure and energy density (called its equation of state, or w) is measured to a precision of about 5% today. But in the next five years, new observations, including those with a special camera fitted onto a telescope in Chile called the Dark Energy Survey , will increase the precision to 2% or 3%, says Mortonson. Future ground- and space-based missions, including a planned European space mission called Euclid and a possible US probe called WFIRST , could make even finer measurements.
These missions will not only probe the expansion history of the universe but also chronicle how the distribution of matter has changed over time. One way to do this is with a method called weak gravitational lensing, which looks for distortions in the light from distant galaxies due to any mass that the light passes on its way to a telescope. If dark energy changes over time or if gravity behaves unexpectedly at large scales, we might see evidence of it in the changing “clumpiness” of matter over space and time.
But Eisenstein points out that there are always going to be exotic dark energy models that behave just like the cosmological constant. “The worry is that if we do all these very accurate measurements, and it still looks like a cosmological constant, then we haven’t actually ruled out a lot of the models,” he says. “I think we have a major challenge on the theory side to try to understand what else we can look for.”
“[To understand] dark energy, we will probably require more time, and I would say not less than 10 years,” says Pettorino.
But it’s worth trying to get to the bottom of the mystery, say the researchers. “We thought we had four forces of nature: gravity, electromagnetism, and the weak and strong nuclear forces. Dark energy is either some new force, or some substantial modification to gravity,” says Eisenstein. “It’s a major actor in cosmology and in the history of the universe.”
Then
quote:
Dark energy survey result dims hope for cosmological constant
January 10,2024
A dark energy survey 10 years in the making has made a surprise finding, suggesting that the theory of the expansion of the universe might not be correct.
The final Dark Energy Survey (DES) measurement was released at the 243rd American Astronomical Society meeting in New Orleans and published on pre-print server arXiv.
Dark energy is dark matter’s even more elusive cousin. Studies have suggested that dark energy is estimated to make up almost 70% of the observable Universe and is immensely important for measurements of the acceleration of the Universe’s expansion. But, scientists also have no idea what it is.
One theory is that this dark energy should fit nicely into something called the ‘cosmological constant’ which Einstein added, and then removed, from his calculations into general relativity.
Although Einstein tossed it, it was later revived when it was realised that the universe was expanding at an accelerating rate.
Supernova ‘standard candles’ not so standard after all
“Einstein’s concept of the cosmological constant could actually explain dark energy if it had a positive value (allowing it to conform to the accelerating expansion of the cosmos),” said Professor Robert Nichol, a member of the DES collaboration in a piece for The Conversation. Nichol is also a Pro Vice Chancellor at the University of Surrey.
If dark energy is the cosmological constant, the “equation of state” of dark energy would equal -1. The DES used the best space object we have to try and measure this equation of state – Type Ia supernovae or ‘standard candles’. These are stellar explosions which release consistently bright flashes, allowing researchers to measure how far away they are in the Universe.
“It is very exciting times to see this innovative technology to harness the power of large astronomical surveys”, says one of the researchers, Dr Anais Möller from Swinburne University of Technology.
“Not only we are able to obtain more type Ia supernovae than before, but we tested these methods thoroughly as we want to do more precision measurements on the fundamental physics of our universe.”
An international team of more than 100 scientists mapped an area almost one-eighth of the sky using the 570-megapixel Dark Energy Camera. They took data for 758 nights across six years.
But the results, weren’t what they were expecting. Instead of an equation of state of -1, the end result from the DES was -0.8.
That’s a pretty large difference in astronomy terms, and would suggest that the cosmology constant is wrong. But scientists aren’t so sure yet.
First there’s the error bars – about plus or minus 0.18. Combined with data from the ESA’s Plank telescope the uncertainty is large enough that there’s still a 5% chance of -1.
That’s only a 1 in 20 odds, not ideal, but the results aren’t sure enough for researchers to confirm either way.
“As usual, scientists want more data,” said Nichol.
“The DES results suggest that our new techniques will work for future supernova experiments with ESA’s Euclid mission (launched July 2023) and the new Vera Rubin Observatory in Chile.”
[ Originally published by Cosmos as Dark energy survey result dims hope for cosmological constant ]

It was only a matter of time until the numbers did not match up.
I have mixed feelings :
I feel it is a blow to see the absolutely perfect critical density Dark Energy number miracle fall apart.
But, the (um)clue is a fortunate one, if one values science. It is actually scary to think that a pure coincidence could have caused us to assume all of the expansion of space was due to a "cosmological constant" when our perfect number inflation observation was more of an artifact fluke.
(The more logical heads always knew that the number match value, per the Ia supernova observations, could be just a coincidence, as coincidences can and do happen all the time. Not all observations carry the same weight. This 25 year old - now obsolete - "cosmological constant" is an example of an observation that always could have been interpreted differently)
(A good example of a non-coincidence example would be the hypothetical VHS tape of an alternate universe 1983 AFC Championship game featuring John Elway & the L.A. Raiders defeating Dan Marino's Baltimore Colts at Memorial Stadium in early 1984, then a tape of the Raiders beating the Redskins in the Superbowl with Van McCelroy winning the MVP after intercepting a pass and making 6 tackles. A piece of evidence for a Quantum Tuner, it would be! If only...)

Replies to this message:
 Message 3 by Tanypteryx, posted 04-09-2024 9:31 AM LamarkNewAge has replied
 Message 4 by Percy, posted 04-09-2024 9:40 AM LamarkNewAge has replied
 Message 5 by Taq, posted 04-09-2024 1:03 PM LamarkNewAge has replied

  
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Message 2 of 53 (917479)
04-09-2024 8:00 AM


Thread Copied from Proposed New Topics Forum

  
Tanypteryx
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Posts: 4597
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 9.1


Message 3 of 53 (917480)
04-09-2024 9:31 AM
Reply to: Message 1 by LamarkNewAge
04-09-2024 12:52 AM


(Copenhagen is still about to get buried overnight, when psychic studies are finally released

The relevant study, released in January (But the developing results have been leaked for years).
Really? Psychic studies?
I feel it is a blow to see the absolutely perfect critical density Dark Energy number miracle fall apart.
So, I think it's interesting that the microwave background observations indicate a different expansion rate for the Universe than the observations of Type 1A supernovae, but it seems clear that they must not be measuring the exact same thing, one or the other, or both, have some unknown factors that are skewing the results.
I'm not sure what you want to discuss, or if you really meant psychic studies and miracles, or if it's your personal feelings about cosmology as if you have a stake in the final explanation?

Stop Tzar Vladimir the Condemned!
What if Eleanor Roosevelt had wings? -- Monty Python
One important characteristic of a theory is that it has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie
If evolution is shown to be false, it will be at the hands of things that are true, not made up. --Percy
The reason that we have the scientific method is because common sense isn't reliable. -- Taq
Why should anyone debate someone who doesn't know the subject? -- AZPaul3

This message is a reply to:
 Message 1 by LamarkNewAge, posted 04-09-2024 12:52 AM LamarkNewAge has replied

Replies to this message:
 Message 6 by LamarkNewAge, posted 04-09-2024 2:18 PM Tanypteryx has replied

  
Percy
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Posts: 22953
From: New Hampshire
Joined: 12-23-2000
Member Rating: 6.8


Message 4 of 53 (917481)
04-09-2024 9:40 AM
Reply to: Message 1 by LamarkNewAge
04-09-2024 12:52 AM


Can't tell where you're going with this, but the big cosmological questions of our time are:
  1. What is dark energy?
  2. What is dark matter?
  3. Are all studies and experiments forever doomed to validate the Standard Model?
--Percy

This message is a reply to:
 Message 1 by LamarkNewAge, posted 04-09-2024 12:52 AM LamarkNewAge has replied

Replies to this message:
 Message 7 by LamarkNewAge, posted 04-09-2024 2:40 PM Percy has seen this message but not replied

  
Taq
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Posts: 10302
Joined: 03-06-2009
Member Rating: 7.0


Message 5 of 53 (917486)
04-09-2024 1:03 PM
Reply to: Message 1 by LamarkNewAge
04-09-2024 12:52 AM


LamarkNewAge writes:
But, the (um)clue is a fortunate one, if one values science. It is actually scary to think that a pure coincidence could have caused us to assume all of the expansion of space was due to a "cosmological constant" when our perfect number inflation observation was more of an artifact fluke.
The cosmological constant was thrown out a long time ago once we observed that the universe was expanding. The CC was something Einstein threw in because he thought the universe was eternal and static, so there had to be something that perfectly balanced the universe between expanding and contracting. Once we understood that the universe wasn't static then there was no need for the CC.
Could the CC make a comeback? Maybe. That's what the article you quoted was suggesting. However, the CC isn't a part of modern Big Bang models, so it isn't a problem if the CC is not brought back.
But I doubted the Dark Energy was very good proof of the perfect "cosmological constant".
Who is saying that Dark Energy is good proof of the CC? Einstein called the CC his biggest mistake, and that was before the discovery of dark energy.

This message is a reply to:
 Message 1 by LamarkNewAge, posted 04-09-2024 12:52 AM LamarkNewAge has replied

Replies to this message:
 Message 8 by LamarkNewAge, posted 04-09-2024 3:02 PM Taq has replied

  
LamarkNewAge
Member
Posts: 2497
Joined: 12-22-2015


Message 6 of 53 (917492)
04-09-2024 2:18 PM
Reply to: Message 3 by Tanypteryx
04-09-2024 9:31 AM


quote:
"(Copenhagen is still about to get buried overnight, when psychic studies are finally released

The relevant study, released in January (But the developing results have been leaked for years)."

Really? Psychic studies?
The relevant study had to do with what I quoted. The Chilean observatory DES study.
The other issue:
Copenhagen has a theoretical "COLLAPSE" of the wave function. Undefined numbers of particle get "observed" and the quantum superposition (in Hibbert space) of these particles (however many and in what conglomeration?) collapses, and then classical physics kicks in (at some undefined size boundary, when the quantum object world becomes a classical object.
The Many Worlds Interpretation also has an undefined particle number problem in the first field issue of play, but the conglomeration field is much cleaner: There exists a UNIVERSAL wave function with NO COLLAPSE from Hibbert Space. Instead the entire Universe doubles, perhaps trillions of times - per each individual particle (?) - in a fraction of a second.
(Yes, that means each individual rat, eating cheese in China, has many trillions of particles in which each little quark - on a single rat hair - creates trillions of copies of YOU per FRACTION OF A SECOND.)
Physicist Donnie Deutch feels that the very early stage of the universe splitting is not yet a complete separation into a totally isolated into its self contained, internally consistent isolation. Interactions are still going on, while Sean Carroll defines the complete split slightly earlier.
Quantum Reports | Free Full-Text | Many-Worlds: Why Is It Not the Consensus?
Quantum Reports | Special Issue : The Many-Worlds Interpretation of Quantum Mechanics
MDPI - Publisher of Open Access Journals
quote:
So, I think it's interesting that the microwave background observations indicate a different expansion rate for the Universe than the observations of Type 1A supernovae, but it seems clear that they must not be measuring the exact same thing, one or the other, or both, have some unknown factors that are skewing the results.
The early universe, at 379,000 years old, is clearly "flat". Per CMB.
I dont think there is debate on the first 380,000 years.
The expansion rate of the universe, per Type 1A SUPERNOVAE observations, never has had exactly identical numbers per observation. My way of saving a flat universe (my excuse) was to consider the tiny percentage of the universe containing galaxies as a type of hypothetical gravity trap which stalls the creation of space, per some unknown physical property of gravity. And the effects of the conglomerated gravity radiate outward (some unknown distance) an manipulate the dark energy (whatever it is exactly) in a way the changed the amount of space created.
quote:

I'm not sure what you want to discuss, or if you really meant psychic studies and miracles, or if it's your personal feelings about cosmology as if you have a stake in the final explanation?
What is magic to one generation is science to another.
What is a miracle to one generation is part of the known physical laws of the universe to another.
Stephen Hawking said something - once controversial - that became part of the lyrics of a 1990s song. He said FOR MILLIONS OF YEARS MAN LIVED WITH THE DINOSAURS. Birds, indeed.

This message is a reply to:
 Message 3 by Tanypteryx, posted 04-09-2024 9:31 AM Tanypteryx has replied

Replies to this message:
 Message 9 by Tanypteryx, posted 04-09-2024 3:10 PM LamarkNewAge has replied

  
LamarkNewAge
Member
Posts: 2497
Joined: 12-22-2015


Message 7 of 53 (917495)
04-09-2024 2:40 PM
Reply to: Message 4 by Percy
04-09-2024 9:40 AM


quote:
Can't tell where you're going with this, but the big cosmological questions of our time are:

What is dark energy?
What is dark matter?
Are all studies and experiments forever doomed to validate the Standard Model?
Dark Energy being understood has just about the same chance of us finding a complete cure to every single type of cancer, a complete cure to hardening arteries, a completely safe & cheap prevention pill for blood clots, and a discovery of a medicine that stalls and then reverses aging.
We better hope those quantum computers, we are developing, can tune into & receive signals from a parallel universe that is already millions of years into the future, so we can get all these things downloaded.
As for the majority view of particle physics:
The biggest question is whether one can solve the two totally different sets of physical laws that divide the quantum world from the classical world. Per Copenhagen, the quantum world has different physical laws than classical physics. But the size barrier is undefined.
Many Worlds proponents say the problem is already solved. We are all living in the quantum world. There is no size barrier that divides a classical object from a quantum object.
You are a quantum pea.
It is all a grand unified quantum physics.
(String Theory has its critics, like Bret/Eric Weinstein, and problems abound, granted)

This message is a reply to:
 Message 4 by Percy, posted 04-09-2024 9:40 AM Percy has seen this message but not replied

  
LamarkNewAge
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Posts: 2497
Joined: 12-22-2015


Message 8 of 53 (917496)
04-09-2024 3:02 PM
Reply to: Message 5 by Taq
04-09-2024 1:03 PM


quote:
The cosmological constant was thrown out a long time ago once we observed that the universe was expanding. The CC was something Einstein threw in because he thought the universe was eternal and static, so there had to be something that perfectly balanced the universe between expanding and contracting. Once we understood that the universe wasn't static then there was no need for the CC.
One has to know the composition of the universe, the rough age of the universe, and many other physical properties, forces, fields, etc. to even come close to understanding the inflation of the universe and the results of its interactions.
Einstein was at even more of a disadvantage than we are in. He lived the vast majority of his life before 1950.
He could not help but be wrong, whether he accepted a CC or not.
quote:
Could the CC make a comeback? Maybe. That's what the article you quoted was suggesting. However, the CC isn't a part of modern Big Bang models, so it isn't a problem if the CC is not brought back.
A Cosmological Constant DID make a comeback - in 1998, and it is not a stretch to say that most cosmologists felt that Dark Energy was proof of the Cosmological Constant, especially when the observations produced results that backed up a completely flat universe at exactly 100% the critical density needed for a 100% flat universe.
The 2024 story is that the newer Dark Energy version of the Cosmological Constant had a life that spanned from 1998-2024, then it died.
Dark Energy exists but there could be literally 100 different drivers that constitute its total value.
(Some sort of constant might make up a certain percentage of its total whole, but good luck sorting that one out)
And its total value is not certain, though there is a range.

This message is a reply to:
 Message 5 by Taq, posted 04-09-2024 1:03 PM Taq has replied

Replies to this message:
 Message 10 by Taq, posted 04-09-2024 3:12 PM LamarkNewAge has replied

  
Tanypteryx
Member
Posts: 4597
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 9.1


Message 9 of 53 (917497)
04-09-2024 3:10 PM
Reply to: Message 6 by LamarkNewAge
04-09-2024 2:18 PM


The relevant study had to do with what I quoted. The Chilean observatory DES study.
Really? I couldn't find anything related to "psychic studies."
The early universe, at 379,000 years old, is clearly "flat". Per CMB.

I dont think there is debate on the first 380,000 years.
Well, it wasn't the cosmic microwave background when it was emitted. And we are trying to compare observations made here and now on Earth of events that occurred in the distant past.
quote:

I'm not sure what you want to discuss, or if you really meant psychic studies and miracles, or if it's your personal feelings about cosmology as if you have a stake in the final explanation?
What is magic to one generation is science to another.
What is a miracle to one generation is part of the known physical laws of the universe to another.
You seem to be taking us from science to magic and miracles, rather than the other way around.
This hasn't made it any clearer what you want to discuss.
The expansion rate of the universe, per Type 1A SUPERNOVAE observations, never has had exactly identical numbers per observation.
I think that can be said for any scientific observations. Exactly identical numbers per observation would be a clue that you might have a problem with your equipment or your analysis.

Stop Tzar Vladimir the Condemned!
What if Eleanor Roosevelt had wings? -- Monty Python
One important characteristic of a theory is that it has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie
If evolution is shown to be false, it will be at the hands of things that are true, not made up. --Percy
The reason that we have the scientific method is because common sense isn't reliable. -- Taq
Why should anyone debate someone who doesn't know the subject? -- AZPaul3

This message is a reply to:
 Message 6 by LamarkNewAge, posted 04-09-2024 2:18 PM LamarkNewAge has replied

Replies to this message:
 Message 11 by LamarkNewAge, posted 04-09-2024 3:30 PM Tanypteryx has replied

  
Taq
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Posts: 10302
Joined: 03-06-2009
Member Rating: 7.0


(1)
Message 10 of 53 (917498)
04-09-2024 3:12 PM
Reply to: Message 8 by LamarkNewAge
04-09-2024 3:02 PM


LamarkNewAge writes:
A Cosmological Constant DID make a comeback - in 1998, and it is not a stretch to say that most cosmologists felt that Dark Energy was proof of the Cosmological Constant
From my limited understanding as a physics layperson . . .
The accelerating expansion of the universe is the evidence for dark energy. It is no different than watching two masses being attracted to one another and calling it gravity. I don't understand why CC even has to be brought into the conversation because dark energy already encompasses what is being observed.

This message is a reply to:
 Message 8 by LamarkNewAge, posted 04-09-2024 3:02 PM LamarkNewAge has replied

Replies to this message:
 Message 12 by LamarkNewAge, posted 04-09-2024 3:38 PM Taq has replied

  
LamarkNewAge
Member
Posts: 2497
Joined: 12-22-2015


Message 11 of 53 (917503)
04-09-2024 3:30 PM
Reply to: Message 9 by Tanypteryx
04-09-2024 3:10 PM


quote:
Really? I couldn't find anything related to "psychic studies."
I thought is said that was a "hypothetical" study and/or an unreleased study.
I started talking about Many Worlds because many have long speculated that Hibbert Space takes the UNIVERSAL UNCOLLAPSING macro-particle (entire universe) conglomeration "ray" to the hypothetical multiverse real-estate.
In a flat universe, with both early ​(first fraction of a second) Inflation, plus (separately) physical laws brought by an infinite local universe expansion (via Dark Energy), there is a place for these ever duplicating macro-particles (our duplicating universe!) to go.
quote:
Well, it wasn't the cosmic microwave background when it was emitted. And we are trying to compare observations made here and now on Earth of events that occurred in the distant past.

I would consider the question to be the accuracy of the measuring technique and the resolution of the image. Do have any comments on how recent the CMB data brings us to a clear picture, and how clear would you call the picture?
On the Type IA Supernovae observations, and the never matching values in the light shift measurements:
quote:
I think that can be said for any scientific observations. Exactly identical numbers per observation would be a clue that you might have a problem with your equipment or your analysis.
CMB and Type IA Supernova observations are clearly different techniques.
Both are trying to see what speed the inflation of the universe was moving at and at what time.
CMB has a great ability to let us look at the topography an spatial dimensions

This message is a reply to:
 Message 9 by Tanypteryx, posted 04-09-2024 3:10 PM Tanypteryx has replied

Replies to this message:
 Message 21 by Tanypteryx, posted 04-09-2024 6:08 PM LamarkNewAge has replied

  
LamarkNewAge
Member
Posts: 2497
Joined: 12-22-2015


Message 12 of 53 (917505)
04-09-2024 3:38 PM
Reply to: Message 10 by Taq
04-09-2024 3:12 PM


quote:
The accelerating expansion of the universe is the evidence for dark energy. It is no different than watching two masses being attracted to one another and calling it gravity. I don't understand why CC even has to be brought into the conversation because dark energy already encompasses what is being observed.
You seem to be saying there is no practical value to knowing what Dark Energy comes from.
I massively disagree, especially if it is relevant to alternate universes.
Inflation is 100% relevant to the multiverse ( whether alternate universes exist or not), as all can agree.
String Theory is highly relevant to the early cosmic inflation.
Dark Energy is also relevant to whether you get crushed like a quantum bug.

This message is a reply to:
 Message 10 by Taq, posted 04-09-2024 3:12 PM Taq has replied

Replies to this message:
 Message 13 by Taq, posted 04-09-2024 3:56 PM LamarkNewAge has replied

  
Taq
Member
Posts: 10302
Joined: 03-06-2009
Member Rating: 7.0


(1)
Message 13 of 53 (917508)
04-09-2024 3:56 PM
Reply to: Message 12 by LamarkNewAge
04-09-2024 3:38 PM


LamarkNewAge writes:
You seem to be saying there is no practical value to knowing what Dark Energy comes from.
No. I am saying that the CC doesn't seem to have any practical value, at least in the eyes of this poorly informed physics layman.

This message is a reply to:
 Message 12 by LamarkNewAge, posted 04-09-2024 3:38 PM LamarkNewAge has replied

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 Message 14 by LamarkNewAge, posted 04-09-2024 4:17 PM Taq has replied

  
LamarkNewAge
Member
Posts: 2497
Joined: 12-22-2015


Message 14 of 53 (917514)
04-09-2024 4:17 PM
Reply to: Message 13 by Taq
04-09-2024 3:56 PM


Dark Energy has a measurable value.
What is your opinion on the average number value of Dark Energy?

This message is a reply to:
 Message 13 by Taq, posted 04-09-2024 3:56 PM Taq has replied

Replies to this message:
 Message 15 by Taq, posted 04-09-2024 4:35 PM LamarkNewAge has replied

  
Taq
Member
Posts: 10302
Joined: 03-06-2009
Member Rating: 7.0


Message 15 of 53 (917516)
04-09-2024 4:35 PM
Reply to: Message 14 by LamarkNewAge
04-09-2024 4:17 PM


Re: Dark Energy has a measurable value.
LamarkNewAge writes:
What is your opinion on the average number value of Dark Energy?
I don't have an opinion on it. It is my understanding that the value ascribed to dark energy is just a product of how much acceleration is measured in the expansion of space. It's like asking my opinion on the speed of light.

This message is a reply to:
 Message 14 by LamarkNewAge, posted 04-09-2024 4:17 PM LamarkNewAge has replied

Replies to this message:
 Message 16 by LamarkNewAge, posted 04-09-2024 4:40 PM Taq has replied

  
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