'Universe Breaking' results from JWST -- What does this mean?

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In summary: The problem with this is that the "most massive galaxies" at these redshifts are expected to be in the form of massive elliptical galaxies, which are not detected in the surveys.What Causes The "Impossible Early Galaxies" Problem?There are a number of potential causes for the "impossible early galaxies" problem.One possibility is that the "most massive galaxies" at these redshifts are not actually massive elliptical galaxies, but something else entirely.Another possibility is that the "most massive galaxies" at these redshifts do not actually exist, but are instead just theoretical constructs that astronomers have created to account for the observations that
  • #1
Cerenkov
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Hello.

I was wondering if the experts here would like to comment on this news?

Thus far I've been unable to find a link to any science paper.

Thank you,

Cerenkov.
 
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  • #2
1. What news?
2. If there is no science paper, why do we care?
 
  • #4
Vanadium 50 said:
1. What news?
2. If there is no science paper, why do we care?

The fact that I care to place my trust in the experts in this forum?

Is that a good enough reason why?
 
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  • #6
The New Paper In Nature

The paper in question (and its abstract) which were linked to in the news report referenced above, is as follows (footnotes in the abstract omitted):
Galaxies with stellar masses as high as ~ 1011 solar masses have been identified out to redshifts z ~ 6, approximately one billion years after the Big Bang. It has been difficult to find massive galaxies at even earlier times, as the Balmer break region, which is needed for accurate mass estimates, is redshifted to wavelengths beyond 2.5 μm. Here we make use of the 1-5 μm coverage of the JWST early release observations to search for intrinsically red galaxies in the first ≈ 750 million years of cosmic history. In the survey area, we find six candidate massive galaxies (stellar mass > 1010solar masses) at 7.4 ≤ z ≤ 9.1, 500–700 Myr after the Big Bang, including one galaxy with a possible stellar mass of ~1011 solar masses. If verified with spectroscopy, the stellar mass density in massive galaxies would be much higher than anticipated from previous studies based on rest-frame ultraviolet-selected samples.

Labbé, I., van Dokkum, P., Nelson, E. et al. "A population of red candidate massive galaxies ~600 Myr after the Big Bang." Nature (February 22, 2023). https://doi.org/10.1038/s41586-023-05786-2

Why Is This Paper Important?

The Bottom Line

The paper is notable because it is the most extreme and definitive example of astronomy observations that give rise to the "impossible early galaxy problem" of the LamdaCDM model which is often described as the "Standard Model of Cosmology."

Simply put, the LambdaCDM model predicts that the formation of galaxies of this size should take place far later after the Big Bang than the time frames in which they have been observed by astronomers to exist.

Previous LambdaCDM Galaxy Formation Predictions Compared

One widely accepted prediction was made by astrophysicist Carlos Frenk at a scientific conference in October of 1998 based upon LambdaCDM simulations had been that there would be no galaxies before redshift z=7. This corresponds to a look back time of 13.01 billion years, which is about 770 million years after the Big Bang, which implies that galaxies start forming about 55% to 10% more slowly in the LambdaCDM model than the earliest galaxies must start to form given what has been observed to form so far by the JWST. And, new observations of earlier galaxies over the lifetime of the JWST's mission can only make that gap worse, not weaker, if even earlier galaxies are located.

Like most things in astronomy and cosmology, this LambdaCDM prediction for the time period in which galaxies start to form had a margin of error, but it wasn't a big one and had largely been confirmed by later calculations and simulations made in using the bare LambdaCDM model over the next quarter of a century. And, the LambdaCDM model was so admirable, in part, because it had so few complications and parameters to leave wiggle room in its predictions, and yet was still a good fit to the data for decades.

But now, the new paper in Nature is reporting six reasonably large galaxies at redshifts of z=7.4 ≤ z ≤ 9.1, which at the high end, is much earlier in time than Frenk's LambdaCDM model prediction of z=7. Frenck's 1998 prediction has been only slightly tweaked over the next quarter century and is a precise enough prediction to be significantly different, statistically, from the results announce in the new paper in Nature.

The Impossible Early Galaxies Problem

A published paper from 2016 articulated the "impossible early galaxies" problem as follows:
The current hierarchical merging paradigm and ΛCDM predict that the z∼ 4-8 universe should be a time in which the most massive galaxies are transitioning from their initial halo assembly to the later baryonic evolution seen in star-forming galaxies and quasars. However, no evidence of this transition has been found in many high-redshift galaxy surveys including CFHTLS, Cosmic Assembly Near-infrared Deep Extragalactic Survey (CANDELS), and Spitzer Large Area Survey with Hyper-Suprime-Cam (SPLASH), which were the first studies to probe the high-mass end at these redshifts. Indeed, if halo mass to stellar mass ratios estimated at lower-redshift continue to z∼ 6-8, CANDELS and SPLASH report several orders of magnitude more M∼ 1012-13M⊙ halos than is possible to have been formed by those redshifts, implying that these massive galaxies formed impossibly early.

We consider various systematics in the stellar synthesis models used to estimate physical parameters and possible galaxy formation scenarios in an effort to reconcile observation with theory. Although known uncertainties can greatly reduce the disparity between recent observations and cold dark matter merger simulations, there remains considerable tension with current theory even if taking the most conservative view of the observations.
Steinhardt, Charles. L. ; Capak, Peter; Masters, Dan; Speagle, Josh S., "The Impossible Early Galaxies Problem" 824(1) The Astrophysical Journal, article id. 21, 9 pp. (June 2016). DOI: 10.3847/0004-637X/824/1/21 (open access copy available at arXiv:1506.01377).

Thus, there were strong observational hints that there might be an "impossible early galaxy problem", for example, from the Hubble space telescope's observations and other "telescopes" (using the term loosely to describe a variety of astronomy instruments) that can probe highly redshifted objects long before the paper above published yesterday in Nature based upon JWST observations was released.

But, since the James Webb Space Telescope is so much more powerful than any earlier telescope when it comes to probing high redshift objects, what were previously strong hints that there might be big galaxies very soon after the Big Bang turned almost immediately after the JWST came online into multiple clear and unequivocal examples of galaxies of given sizes long before LambdaCDM said that they should exist. The JWST has also seen more galaxies at higher redshifts (i.e. more recently after the Big Bang) than any other "telescopes" before it has (even though it has been on line only briefly). This paper discusses the oldest galaxies seen to date, just 500-700 million years after the Big Bang, that look far more like modern galaxies than the LambdaCDM model should have made possible at this early time period in the universe.

To oversimplify the narrative somewhat, LambdaCDM assumes that in the early universe clumps of dark matter start to accumulate from random differences in matter density, which make it possible for ordinary matter to become concentrated enough to form stars, which in turn end up in clumps of proto-galaxies. These clumps undergoing a "hierarchal" process of repeated mergers and the collide into each other, until they eventually form modern sized galaxies.

The LambdaCDM model, once its six parameters are fitted to astronomy observations, provides data that makes it possible to make reasonable estimates of the rate at which dark matter becomes clumpy, the rate at which stars form, and the rate at which mergers occur, from which it is possible to make reasonable estimates of when galaxies of a certain size ought to appear.

But evidence provided by the JWST, exemplified by this paper with the earliest examples of early galaxies, makes clear that either something about the calculations used to make those predictions, or the LambdaCDM model itself, are wrong in this respect.

The jury is out regarding why galaxies formed much earlier than expected in the LambdaCDM model, even though something is clearly amiss.

What About The LambdaCDM Model Does This Paper Show Is Broken?

One of the main pieces of experimental evidence that previously inspired confidence in the accuracy of the LambdaCDM model was its ability to describe essentially all cosmological scale observations at a large scale structure level with just six astronomy observation fixed parameters, each of which has been measured with some precision.

The LambdaCDM model, once its six parameters are fitted, is, for example, an extraordinarily good match to the observed pattern of the cosmic background radiation (CMB) which came into being during the "recombination era" about 0.38 million years after the Big Bang. (See generally here for the conventional chronology of the universe after the Big Bang in cosmology.) Star and galaxy formation can't happen in any appreciable amount until after the recombination era when ordinary matter and photons (i.e. "radiation") decouple from each other because protons and electrons have been bound together into neutral atoms and the temperature of the universe has cooled sufficiently to allow for greater clumping of matter. So, we think that LambdaCDM gets the "starting line" of the star and galaxy formation process right even after this new paper.

But, the new paper's observations imply that the universe went from giving birth to its first stars after recombination ended, to producing galaxies similar in scale to many galaxies we see today at very low redshifts (about 13,780 million years after recombination), in just 500 to 700 million years. This strongly suggests that some other part of the LambdaCDM model, that crops up later in the history of galaxy formation in the universe and the larger span of the chronology of cosmology, is broken.

Are The Observations In This Paper Credible And Likely To Hold Up?

This result is highly credible because it confirms pre-JWST strong hints that these early galaxies existed. As noted above "high-redshift galaxy surveys including CFHTLS, Cosmic Assembly Near-infrared Deep Extragalactic Survey (CANDELS), and Spitzer Large Area Survey with Hyper-Suprime-Cam (SPLASH)" were already pointing to this result seven years ago, although much more equivocally than the new data from the JWST does.

The new paper's results are also credible observations because many other JWST observations also identify early galaxies, even though they have not yet been published, have been released to the public, and in some cases have been disclosed in preprints of articles that have been accepted for publication in leading astronomy journals (e.g. here and here and here). So, independent confirmations of the existence of early galaxies established in the Nature article using JWST observation of other candidate galaxies at very high redshifts over the course of the next year or so, are a near certainty.

Another reason that this result is credible is that the impossible early galaxy problem with the LambdaCDM model isn't the only recent crack in that model's predictions.

A full review of discrepancies between astronomy observations and the LambdaCDM model is beyond the scope of this thread. But it suffices to say that there are half a dozen or a dozen or so distinct and independent discrepancies between LambdaCDM model predictions and astronomy observations that are currently being actively investigated in areas that range from galaxy and galaxy cluster observations to different kinds of cosmology scale observations.

Some of those discrepancies may turn out to be experimental methodology issues or require slight tweaks to how the LambdaCDM predictions are calculated that are no big deal in the greater scheme of things. Others discrepancies, however, may turn out to be as serious a challenge to the LambdaCDM model as the impossible early galaxy problem that the new paper in Nature has highlighted.

This is a very different situation than the one that exists for the Standard Model of Particle Physics, where every time a discrepancy or tension between the Standard Model's predictions and experiment has cropped up over the last half century (except with respect to neutrino mass), it has subsequently promptly been ruled out with more experiments and better analysis, and there are only a few weak discrepancies between the Standard Model and experiment currently in play.

So, the scientific community is already primed right now to be more receptive to challenges to the "Standard Model of Cosmology" than it is to tensions between experimental results and the Standard Model of Particle Physics.

Alternatives To The LambdaCDM Model

If the LambdaCDM model is "broken" what alternatives exist to it?

There are multiple possible ways that the LambdaCDM model could be tweaked. One of those many possible alternatives is to look at a gravity based explanation of dark matter phenomena.

Models that attempt to explain dark matter phenomena with a modification to the laws of gravity or how they operate, rather than with dark matter particles, generically predict earlier galaxy formation than the LambdaCDM model does, consistent with the new JWST observations.

For example, galaxies were predicted to form in the time frame now observed by Bob Sanders in October of 1997 in the MOND (modified Newtonian dynamics) paradigm which is the most widely discussed gravitation based approach to explaining dark matter phenomena, even though it is itself a mere phenomenological toy model theory. Sanders predicted that: “Objects of galaxy mass are the first virialized objects to form (by z=10) and larger structure develops rapidly.” This is a little less than 500 million years after the Big Bang.

A JWST observation of a galaxy that may be as earlier as z=9.1 after only an initial quick search shortly after it has become operational, is consistent with that prediction and is at odds with the LambdaCDM prediction.
 
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  • #7
Without a scientific paper there is little to discuss beyond "Yay team!!"

I don't see how nobody noticed that the paper linked was heavily redacted - including having all the figures removed. How can we discuss that?

The paper does not use spectroscopic redshifts. Photometric redshifts are essentially guesses, A population of galaxies that appears gigantic and old might just be smaller, closer and redder. Or it might not. Can't tell with what is out there.

Go team go!
 
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  • #8
Vanadium 50 said:
Without a scientific paper there is little to discuss beyond "Yay team!!"

I don't see how nobody noticed that the paper linked was heavily redacted - including having all the figures removed. How can we discuss that?

The paper does not use spectroscopic redshifts. Photometric redshifts are essentially guesses, A population of galaxies that appears gigantic and old might just be smaller, closer and redder. Or it might not. Can't tell with what is out there.

Go team go!
The open access preprint is at https://arxiv.org/abs/2207.12446

FWIW, it was trivially easy to find.
 
  • #9
ohwilleke said:
FWIW, it was trivially easy to find
Then @Cerenkov should have posted it rather than make us hunt for it.
 
  • #11
Vanadium 50 said:
Then @Cerenkov should have posted it rather than make us hunt for it.

Yes, he should have.

However, despite my shortcomings ohwilleke cared enough to write an excellent reply, pitched for my Basic level understanding.

Thank you for caring ohwilleke.
 
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  • #12
I would be very happy if the experts in this forum could please answer some follow up questions that have occurred to me. Thank you.

1.
Are the masses of the six candidate galaxies in question comparable to the masses of the highly evolved, massive spirals and elliptical galaxies that we see in the local universe? I'm afraid I'm not expert enough to cite numbers here so I can't really make that comparison for myself. Nor do I have a good enough handle on what constitutes galactic masses and how this term is correctly defined.

2.
Is it possible to say if the redness of the six galaxies is due to redshift distance, the presence of large amounts of dust, the possibility that these are 'red and dead' highly evolved galaxies or some combination thereof?

3.
Despite these galaxies appearing to 'break' the LCDM model, would they still be classed as protogalaxies or 'baby' galaxies in the early stages of their evolution?

Thank you for any help given.Cerenkov.
 
  • #14
Cerenkov said:
I would be very happy if the experts in this forum could please answer some follow up questions that have occurred to me. Thank you.

1. Are the masses of the six candidate galaxies in question comparable to the masses of the highly evolved, massive spirals and elliptical galaxies that we see in the local universe? I'm afraid I'm not expert enough to cite numbers here so I can't really make that comparison for myself. Nor do I have a good enough handle on what constitutes galactic masses and how this term is correctly defined.
Basically. They aren't as big as galaxies come, but this is well within the normal range for modern galaxies.
Cerenkov said:
2. Is it possible to say if the redness of the six galaxies is due to redshift distance, the presence of large amounts of dust, the possibility that these are 'red and dead' highly evolved galaxies or some combination thereof?
There are complications to measuring huge redshift distances, but the magnitude of the "noise" or adjustments that have to be made can be quantified and isn't unduly large with a careful analysis relative to the size of the signal.

There is room for reasonable people to disagree on a lot of the technical analysis details - and there have been a lot of these kinds of disagreements in an effort to reconcile the Hubble tension between early and late time measurements of Hubble's constant.

But the JWST's much greater power at high redshifts makes confounds to redshift distance estimates much less significant relative to the core redshift distance estimate than previous "telescopes" (using the term loosely to refer to any kind of instrument used to observe deep space, whether it is looking at visual range light, or radio waves, or X-rays, or the infrared spectrum, or neutrinos, or gravitational waves, or "cosmic rays", or anything else I haven't mentioned).

As the sample size of high redshift galaxies grows, the combined power of the total data set in the fact of potential confounds will grow even stronger.
Cerenkov said:
3.Despite these galaxies appearing to 'break' the LCDM model, would they still be classed as protogalaxies or 'baby' galaxies in the early stages of their evolution?
No. If you want to use an analogy to human development, these are, at a minimum, young adult galaxies. Many will stay that size for many billions of years to come.
 
  • #15
Many thanks for your replies ohwilleke.
I do appreciate them.
I'll be listening to what Sabine has to say later today.

Now to more questions.

Basically. They aren't as big as galaxies come, but this is well within the normal range for modern galaxies.

Aha! Let me just check with you about that word, 'modern'. Do you mean 'local' as in galaxies found within the Local Group, The Virgo Supercluster and the Laniakea Supercluster? Are the terms local and modern interchangeable terms, btw?

But the JWST's much greater power at high redshifts makes confounds to redshift distance estimates much less significant relative to the core redshift distance estimate than previous "telescopes".

So you appear to be saying that the JWST should yield better and more reliable distance-related data than its predecessors?

As the sample size of high redshift galaxies grows, the combined power of the total data set in the fact of potential confounds will grow even stronger.

Applying more pressure on the LCDM, which is 'struggling' to explain the presence of these confounds at these high red shifts? (Or is struggling a too emotive and inaccurate word?)

No. If you want to use an analogy to human development, these are, at a minimum, young adult galaxies. Many will stay that size for many billions of years to come.

But what are they doing there? The LCDM's hierarchical explanation of galaxy assemblage - collapse of dark matter haloes, reionization, Population III stars, etc. - would seem to be at odds with what the JWST is showing us. Isn't this a bit like finding teenagers in a neonatal ward?Thanks,

Cerenkov.
 
  • #16
I don't think I am entirely in agreement on much of what has been written.

Suppose we take the result at face value - that there are too many old, large galaxies. It's not obvious to me that this is anything but a modeling problem. I like modeling problems, and I've spent my career working on several, but the "these galaxies are <cue spooky music> impossible" overstates the case.

Next, these galaxies are small by modern standards. The largest is about LMC-sized, and the others are closer to SMC-sized.

Next, and I have said this before, the redshifts are not measured. They are inferred from photometry. Is the photometric code they use good tp this redshift? The code authors claim it is goof to Z=4, and these are quite a bit farther out. Doesn't make the result wrong, but it should slow down the drawing of extraordinary conclusions.

Related to this, these galaxies aren't just anomalously large. They are anomalously blue. Both anomalies go away if they are closer and younger than the photometry code returns.

Finally, this paper has been in review for months and months. What could the hold-up be? Not the observation - the galaxies are what they are. So it must have been the interpretation (and this is often the case). I have no reason to suspect that the referees didn't notice the same things I noticed, and suspect that the author's winning argument was, as again it often is, "we said what we did, and if people don''t like it, they can write their own papers criticizing it"
 
  • #17
Cerenkov said:
Aha! Let me just check with you about that word, 'modern'. Do you mean 'local' as in galaxies found within the Local Group, The Virgo Supercluster and the Laniakea Supercluster? Are the terms local and modern interchangeable terms, btw?
Age is normally expressed in astronomy in terms of the "z" of redshift value with low values being more recent and high values being older. I am referring to "modern" as low z, realistically z=0 to z=2.
Cerenkov said:
So you appear to be saying that the JWST should yield better and more reliable distance-related data than its predecessors?
Yes. The JWST has much more capacity to see high redshift objects than previous "telescopes."
Cerenkov said:
As the sample size of high redshift galaxies grows, the combined power of the total data set in the fact of potential confounds will grow even stronger.

Applying more pressure on the LCDM, which is 'struggling' to explain the presence of these confounds at these high red shifts? (Or is struggling a too emotive and inaccurate word?)
Yes (or alternately, increasing pressure on the need to identify flaws in how the LCDM predictions were calculated).
Cerenkov said:
Isn't this a bit like finding teenagers in a neonatal ward?
Sort of. More like finding 19-20 year olds in a middle school, in terms of the magnitude of the discrepancy.

The issue is mostly about how long it takes to get to maturity. So, in some ways its more about having a good conversion chart from dog years to person years for galaxies.

LCDM has predicted that it takes a certain amount of time for a "young adult" galaxy to appear, but the evidence says that this prediction was an overestimate. The big question is why that prediction was wrong.
 
  • #18
ohwilleke said:
Age is normally expressed in astronomy in terms of the "z" of redshift value with low values being more recent and high values being older. I am referring to "modern" as low z, realistically z=0 to z=2.

Yes. The JWST has much more capacity to see high redshift objects than previous "telescopes."

Yes (or alternately, increasing pressure on the need to identify flaws in how the LCDM predictions were calculated).

Sort of. More like finding 19-20 year olds in a middle school, in terms of the magnitude of the discrepancy.

The issue is mostly about how long it takes to get to maturity. So, in some ways its more about having a good conversion chart from dog years to person years for galaxies.

LCDM has predicted that it takes a certain amount of time for a "young adult" galaxy to appear, but the evidence says that this prediction was an overestimate. The big question is why that prediction was wrong.
Can I ask what your view on what Sabine said regarding dark matter w.r.t. these results? She tends to make controversial statements so I would like a measured view. She has said that dark matter predictions are not matching up to observations but MOND is.
 
  • #19
ohwilleke said:
More like finding 19-20 year olds in a middle school, in terms of the magnitude of the discrepancy
More still like finding the driver's licenses of a 19-20 year olds on the floor of a middle school.
 
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  • #20
Vanadium 50 said:
More still like finding the driver's licenses of a 19-20 year olds on the floor of a middle school.
These analogies are helping me understand cosmology.
 
  • #21
pinball1970 said:
what Sabine said
Now she is mononymic like Cher, Madonna and Prince?
 
  • #22
Thank you for sounding a note of caution Vanadium 50.Related to this, these galaxies aren't just anomalously large. They are anomalously blue. Both anomalies go away if they are closer and younger than the photometry code returns.A question about this anomalous blueness, if you please.

I realize that you are relating the colour to distance, but could this blueness be a result of many Population III stars being present in these galaxies? It's my naïve understanding that such stars are theorized to radiate not only copious amounts of UV light but also visible light at the blue end of the spectrum. What do you think?

Thanks,

Cerenkov.
 
  • #23
Cerenkov said:
Aha! Let me just check with you about that word, 'modern'. Do you mean 'local' as in galaxies found within the Local Group, The Virgo Supercluster and the Laniakea Supercluster? Are the terms local and modern interchangeable terms, btw?
Age is normally expressed in astronomy in terms of the "z" of redshift value with low values being more recent and high values being older. I am referring to "modern" as low z, realistically z=0 to z=2.Thank you ohwilleke.

To assist my understanding further, do you happen to know of any easily-read graphics or illustrations that show the "z" of redshift calibrated to distance values like light years or parsecs?

Something like the way a tape measure will show both imperial and metric units?

Thank you,

Walter.
 
  • #24
Vanadium 50 said:
Now she is mononymic like Cher, Madonna and Prince?
She has a long second German name it's just easier.
 
  • #25
Cerenkov said:
I realize that you are relating the colour to distance, but could this blueness be a result of many Population III stars being present in these galaxies?
First, I am doing no such thing. The authors are doing that,. That's what photometric redshifts are, And they are not nearly as relaible as spectroscopic redshifts.

Next, sure. They could be exotic objects very far away. And they could be mundane objects that are closer.

You can similarly look at hoofprints and say it could be a centaur or a unicorn.
 
  • #26
Thank you Vanadium 50.So, when you wrote this...

Next, these galaxies are small by modern standards. The largest is about LMC-sized, and the others are closer to SMC-sized.

...are you saying this about the sizes of the galaxies or are the authors saying this?
 
  • #27
The authors give masses. I compared them to masses that you are likely to know about. "Giant" does not mean "like M87". It means "less small than we thought".

No matter what P!nk or Moby might say.
 
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  • #29
can the metallicity or individual masses of these stars be inferred or measured - would it be either presumed or observed that the galaxies consisted of population III stars?
 
  • #30
Closed pending moderation.
 
  • #31
And reopened after removing an off-topic digression
 
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  • #32
BWV said:
can the metallicity...f these stars
Doubtful. They don'y even have a real redshift - just photometry.
 
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  • #33
Vanadium 50 said:
The code authors claim it is goof to Z=4,
OK, this is definitely one of your typos you should definitely fix. :oldbiggrin:

Vanadium 50 said:
Now Sabine is mononymic like Cher, Madonna and Prince?
And Lubos. You forgot Lubos. (Otoh, I wish I could.)
 
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  • #34
pinball1970 said:
Sabine has said that dark matter predictions are not matching up to observations but MOND is.
Stacy McGaugh's blog Triton Station is probably a better source for what's going on with actual data vs theories. He has just now (10-Mar-2023) put out a new post about this. One of the things he reminds is that this business about "big galaxies early" was a prediction of MOND. See his post from 3-Jan-2022.
 
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  • #35
strangerep said:
OK, this is definitely one of your typos you should definitely fix. :oldbiggrin:
More of a Freudian slip. Photometric redfshifts are little better tnan "Golly, it sure looks red". Yes, someimes that's all you have, but it's hard to get excited until the real data - i.e. spectroscopic redshifts - come in.

No matter what Beyonce and JayZ post on their blogs.
 
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