• This is a political forum that is non-biased/non-partisan and treats every person's position on topics equally. This debate forum is not aligned to any political party. In today's politics, many ideas are split between and even within all the political parties. Often we find ourselves agreeing on one platform but some topics break our mold. We are here to discuss them in a civil political debate. If this is your first visit to our political forums, be sure to check out the RULES. Registering for debate politics is necessary before posting. Register today to participate - it's free!

Crisis in Cosmology?

DCCougar

DP Veteran
Joined
Sep 6, 2022
Messages
7,462
Reaction score
8,286
Location
North Idaho
Gender
Male
Political Leaning
Slightly Liberal
I see these YouTube videos about how the Webb telescope is showing "galaxies older than the universe" and other sensationalistic claims. I've seen this sort of thing before in cosmology. Of course, it always turns out to be wrong. Here is the latest:

"Not long after the James Webb Space Telescope began science operations in July 2022, breathless headlines proclaimed that observations of distant galaxies were “breaking theories of cosmic evolution.” Astronomers had found galaxies that appeared much brighter than expected. If all of that light came from stars, then those galaxies would have formed so many stars, so quickly, that the leading theory for the universe’s formation and evolution could not explain them.​
​
New research finds that some of those early galaxies are in fact much less massive than they first appeared. Much of their light came, not from stars, but from a hot accretion disk surrounding a supermassive black hole."​
​
Full article
 
Isn't it nice when science adjusts to new knowledge?
 
I wouldn't classify revising claims as a crisis in science unless its always been in a state of crisis.

Over the past 50 years the most significant discoveries are exo-planets, super massive black holes at the center of galaxies, dark matter and dark energy. The last two are the most shocking. No one would have guessed years ago that all that we see accounts for less than 1/5 or what exists and that the remaining mass is undetectable. On a side note were if not for dark matter...we wouldn't be here.
 
Lol, I read ’cosmetology!’
 
Rexedgar said:
Lol, I read ’cosmetology!’
Click to expand...
""Recently at a New York cocktail party, a young physicist was asked how he made his living and he replied that he was by specialty a cosmologist. While it might be debated whether cosmology constitutes a "living," his host remained undeterred and immediately inquired if it would be possible to make an appointment for a manicure and a haircut."" - Rothman​
 
DrewPaul said:
Over the past 50 years the most significant discoveries are exo-planets, super massive black holes at the center of galaxies, dark matter and dark energy.
Click to expand...
Actually, it's almost 100 years for dark matter, which was posited in 1930 by Fritz Zwicky based on his observations of the Coma Cluster.

And there are still people looking for a different explanation (like "modified gravity"), even in the face of pretty clear confirmation of dark matter by the Bullet Cluster observations.

But Dark Energy -- Wow, nobody saw that one coming -- still pretty recent and darn near wholly unexplained. (Cosmic inflationary residue in the vacuum?)

"....astronomers thus found themselves astounded, if not totally floored, by what supernovae revealed [about the cosmic acceleration]. They have, however, leaped from the carpet, dusted themselves off, and proceeded to investigate the universe." - Goldsmith​
 
DCCougar said:
Actually, it's almost 100 years for dark matter, which was posited in 1930 by Fritz Zwicky based on his observations of the Coma Cluster.
Click to expand...
I guess I should add that Zwicky's work did not receive widespread attention until much later, when similar discrepancies were observed in the rotation curves of individual galaxies by astronomer Vera Rubin and others in the 1970s.
 
DCCougar said:
Science is self correcting, or as Planck said "continually advancing on incontestably safe tracks."
Click to expand...
Completely disagree.
Science follows science. Unusual things occur and science doesn't have the answer to them, but that doesn't mean they shy away from the search.
 
mrjurrs said:
Isn't it nice when science adjusts to new knowledge?
Click to expand...

For about sixty percent of the world, science adjusting to meet new knowledge feels like apostasy and sacrilege.
To this bumbling majority, now fast growing even in America, science is religion and religion is based on sacred laws and edicts carved in stone by the finger of a gigantic bearded old man who lives in the sky and who never lies, thus the changes in science feel like a religion that is based on LIES.

This is the price we amateur libertarians and anarchists pay for generational ignorance; superstition and conspiracy theories valued the same as fact.
 
Be leery of headlines and articles written by laymen and non-scientists that oversimplify and sensationalize astrophysics "facts", because too often we end up with misleading and even downright false conclusions from them.

Astrophysicists use the term "known universe" to describe what we're able to see. From there, they try to determine its size, and thus its age. But it's only ever the size and age of the "known universe". Not "the universe" like layman non-scientist authors and YT content creators might call it.

Since JWST is much more powerful than Hubble, and was always expected to be able to see galaxies much further away than Hubble ever could, the size (and thus age) of the "known universe" was absolutely expected to increase. (In fact, it pretty much doubled last year, from 13 to 26 b/ly.)

But we get laymen and non-scientists saying sensationalist crap like, "This galaxy is older than the universe!" and "That galaxy existed before the Big Bang!" and "This other galaxy is breaking the laws of physics!"

No they're not. The only folks who thought the age & size of the universe were positively known are folks who are not astrophysicists but are trying and failing to speak for them. The author you quoted above used the phrase "the leading theory for the universe’s formation and evolution could not explain them" - what leading theory? The previously-thought age & size. That's it. That's the "leading theory" the author is referring to. And it's not a "leading theory" at all, because no astrophysicist has ever claimed that the known size/age of the universe is the actual size/age of the universe.
 
There are several crises in cosmology.

1) Voids

2) The Hubble Tension. (Unresolved by JWST)

3) Things that shouldn’t exist. (Including large galaxies with old stars observed by JWST when/where the model says they shouldn’t be there)

As for what it all means - there are two camps of physicists. The first camp believes there are new physics which, once we figure out what they are, can be plugged into the existing cosmological model and solve all our problems. The second camp believes the cosmological model and everything we thought we knew about the physical laws is wrong and we need to start from the drawing board.

I tend to side with the later as it is the most loyal to the scientific method. When observation conflicts with theory or model then it is falsified. That falsifiability is what separates science from pseudoscience. Unfortunately, the first camp and the popular practice boils down to insisting that the current cosmological model is not falsifiable and we can just plug the holes by making things up such as dark matter and dark energy. In my view, because of a combination of ego and the fact that no living physicist has the chops to replace it.
 
Binary_Digit said:
Be leery of headlines and articles written by laymen and non-scientists that oversimplify and sensationalize astrophysics "facts", because too often we end up with misleading and even downright false conclusions from them.
Click to expand...
Agreed
Well, if cosmic inflation is anywhere near correct, "the universe" is many, many orders of magnitude larger than the visible universe. That does NOT mean that it began at some time different from the visible universe. It means they began together and have the same age.
What YouTube video did you get THAT from, lol. The size and age of the universe were certainly NOT expected to increase because of the JWST. If anything, the estimated age just became more precise.
Binary_Digit said:
The only folks who thought the age & size of the universe were positively known are folks who are not astrophysicists but are trying and failing to speak for them.
Click to expand...
"Size" is not such an issue since it is changing due to accelerating expansion. But astrophysicists have been narrowing the age of the universe since it was discovered to be expanding. (Before that, it was thought to be "eternal.") At this point it is right around 13.8 billion years, plus or minus a hundred million or so. This is not contested (except perhaps in misguided YouTube videos). The only question is how precise is the estimate. Is it 13.7 or 13.9?
Binary_Digit said:
The author you quoted above used the phrase "the leading theory for the universe’s formation and evolution could not explain them" - what leading theory?
Click to expand...
Well, that would be the FLRW [Friedman-Lemaitre-Robertson-Walker] Big Bang model, coupled with the ΛCDM Model (Lambda Cold Dark Matter model).
Binary_Digit said:
And it's not a "leading theory" at all, because no astrophysicist has ever claimed that the known size/age of the universe is the actual size/age of the universe.
Click to expand...
As I said, the only question about the age of the Universe is the accuracy of the estimate. We are fortunate to be living in an era of precision cosmology.
 
Napoleon said:
There are several crises in cosmology.
1) Voids
Click to expand...
How is that a "crisis"? Voids are the result of gravity acting on the overdensities in the CMB.
Napoleon said:
2) The Hubble Tension. (Unresolved by JWST)
Click to expand...
This "crisis" is simply a matter of narrowing down the estimate of the Hubble constant. Different methods of estimating reach different results, but they're really not that far apart. 68 or 72?
Napoleon said:
3) Things that shouldn’t exist. (Including large galaxies with old stars observed by JWST when/where the model says they shouldn’t be there)
Click to expand...
That's what the link in the OP addresses. The makeup of the most distant galaxies were being misinterpreted -- the observed brightness is not from so many early stars but rather from the early galaxy's black hole accretion disk.
Simplistically false.

"If history has taught us one thing it is that, with hindsight, newly discovered laws always turn out to be quite logical extensions of what we have already known for a long time." -- Gerard 't Hooft​
​
"One can imagine a category of experiments that refute well-accepted theories, theories that have become part of the standard consensus of physics. Under this category I can find no examples whatever in the past one hundred years." -- Steven Weinberg​
Oh please. These are certainly not just "made up."

As to the scientific method....

"Making a model of the universe is like trying to pitch a tent on a moonless night in a howling Arctic wind. The tent is theory. The wind is experiment. When one gets to the precipice, where the secure lands of the known have been left behind and the dark canyons of the unknown fill one's field of view, it becomes very difficult to guess just where to set the tent pegs and to predict which ones will hold once the wind comes up." -- Timothy Ferris​
 
"The current paradigm, ΛCDM, describes the Universe from a fraction of a second after the big bang, when seeds for all the structure we see today were quantum fluctuations on subatomic scales, to the present, 13.80 ± 0.023 Gyr later. ΛCDM is supported by a wealth of cosmological data, from tens of millions of redshifts extending to z = 10 to nanoKelvin measurements of the cosmic microwave background on angular scales down to arcminutes." -- Michael Turner, The Road To Precision Cosmology, 2022​
 
DCCougar said:
How is that a "crisis"? Voids are the result of gravity acting on the overdensities in the CMB.
Click to expand...
The bedrock of cosmology is the cosmological principle - which asserts that matter is evenly and homogeneously distributed on the cosmic scale. But it isn’t. According to our observations, matter is concentrated in clusters and filaments separated by enormous voids.
DCCougar said:
This "crisis" is simply a matter of narrowing down the estimate of the Hubble constant. Different methods of estimating reach different results, but they're really not that far apart. 68 or 72?
Click to expand...
You’re missing the point that the current model doesn’t allow for a difference. That’s why it’s a crisis.
DCCougar said:
That's what the link in the OP addresses. The makeup of the most distant galaxies were being misinterpreted -- the observed brightness is not from so many early stars but rather from the early galaxy's black hole accretion disk.
Click to expand...
That is a hypothesis that might explain some of the observations but not all.
That’s not a refutation of what I said.
DCCougar said:
Oh please. These are certainly not just "made up."
Click to expand...
They literally are. They’re a mathematical invention tailored to solve the conflict between observation and the model. You’re not doing science when you declare your model unfalsifiable because there are unobservable and untestable forces in the universe that don’t do anything other than conveniently reconcile a broken model with what can be observed.
 
The cosmological principle is the notion that the spatial distribution of matter in the universe is uniformly isotropic and homogeneous when viewed on a large enough scale. No, the universe is not perfectly smooth. But the physical laws aren't different in another area of the universe.
Napoleon said:
the current model doesn’t allow for a difference. That’s why it’s a crisis.
Click to expand...
The difference used to be "between 10 and 20 billion years." Now it's "13.80 ± 0.023 billion years." The term "crisis" is a bit sensationalistic.
Napoleon said:
They literally are. They’re a mathematical invention tailored to solve the conflict between observation and the model.
Click to expand...
Ah, so there IS observation involved -- dark matter is not just "made up" or "invented." Yes, stars within galaxies, and galaxies within clusters, are observed to be moving faster than the gravity from the visible matter would indicate. This requires an explanation. Weakly-interacting cold dark matter is currently our best one.
Napoleon said:
You’re not doing science when you declare your model unfalsifiable because there are unobservable and untestable forces in the universe that don’t do anything other than conveniently reconcile a broken model with what can be observed.
Click to expand...
As mentioned, dark matter IS observable through its gravitational effect. We have observed and measured gravitational effects for over 300 years. With General Relativity we have an exceedingly accurate understanding of the effects of gravity. Some seek to explain dark matter by modifying our understanding of gravitational effects. This has not worked out well for both stars within a galaxy and galaxies within clusters.

"Dark matter" IS testable and falsifiable. The fact that humans are made up of baryons and make detections electromagnetically only demonstrates their own shortcomings, not those of the universe.

Of course, dark energy is a completely different topic. Its existence is implied because the space between here and the CMB is observed to be not curved, but flat.
 
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…