What Are the Major Conflicts with Standard Cosmology Models?

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Discussion Overview

The discussion revolves around identifying major problems or conflicts with standard cosmology models. Participants explore various aspects of cosmological theories, including observational data and theoretical implications, without reaching a consensus on specific issues.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants reference external sources listing unsolved problems in cosmology, suggesting a lack of clarity in the field.
  • One participant presents a perceived paradox regarding the observable universe's diameter and the age of the universe, questioning how a universe with a diameter of at least 24 billion light years can be only 13.7 billion years old.
  • Another participant argues that the apparent paradox can be resolved by considering the expansion of the universe and the nature of astronomical distance measurements.
  • There are claims that the further back in time one looks, the larger the universe appears, which some participants challenge, asserting that this reflects a misunderstanding of cosmological principles.
  • Participants discuss the importance of distinguishing between different types of distance measurements in cosmology, such as light travel time versus current distance.
  • One participant suggests that misunderstandings may stem from verbal miscommunication rather than substantive disagreements.
  • Links to online calculators and resources are shared to aid in visualizing cosmological concepts and measurements.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the existence of a paradox regarding the universe's size and age. Multiple competing views are presented, with some arguing for the resolution of the paradox through the expansion of the universe, while others maintain that the original question highlights a significant issue in understanding cosmology.

Contextual Notes

There are unresolved assumptions regarding the definitions of distance in cosmology and the implications of the universe's expansion on observational data. The discussion reflects varying interpretations of cosmological observations and measurements.

Who May Find This Useful

This discussion may be of interest to those exploring cosmological theories, students of physics, and individuals curious about the complexities and debates surrounding the understanding of the universe's structure and evolution.

bill alsept
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Is there a current list of the major problems or conflicts with the standard cosmology models?
 
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Lol, that's the link I just gave him Yenchin!
 
LOL. Guess I was beaten by a few seconds :-P
 
Here's one. The Hubble space telescope can see 12 billion light years of distance in most directions, more in some directions. This can only mean that 12 billion years ago the, (visible to us), universe had a diameter of at least 24 billion light years. And yet it is said to be "only" 13.7 billion years old. Something of a paradox there!
 
Peter Watkins said:
Here's one. The Hubble space telescope can see 12 billion light years of distance in most directions, more in some directions. This can only mean that 12 billion years ago the, (visible to us), universe had a diameter of at least 24 billion light years. And yet it is said to be "only" 13.7 billion years old. Something of a paradox there!
Only if you completely ignore the expansion of the universe.
 
This answer,above, makes no sense. It admits of no reply.
 
Peter Watkins said:
Here's one. The Hubble space telescope can see 12 billion light years of distance in most directions, more in some directions. This can only mean that 12 billion years ago the, (visible to us), universe had a diameter of at least 24 billion light years. And yet it is said to be "only" 13.7 billion years old. Something of a paradox there!
:smile:

Peter, for Heaven's sake learn a little about the heavens. :biggrin:

We see glowing hot gas at a redshift of 1100.

That material will have long since cooled and condensed into galaxies and stars. It is now at a distance of about 45.5 billion lightyears. So that's essentially how far we can see (with a microwave antenna telescope, not the Hubble telescope.)

Distance in astronomy often means the distance NOW---if you could freeze the expansion process at this moment to give yourself time to actually make the measurement. It is not in any simple relationship to the light travel time, or socalled "lookback time."
Popular accounts are often unclear what kind of distance measure they mean---a real instantaneous distance at some moment, or maybe on the other hand a travel time.
 
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  • #10
Peter Watkins said:
This answer,above, makes no sense. It admits of no reply.
Ok then: please explain what the paradox is that you see. Because I see no paradox in those two pieces of information. They do not contradict each other.
 
  • #11
The projected age of the universe gives us a radius, not a diameter. And keep in mind the universe has been expanding during the entire time those ancient photons have been journeying to meet our detectors.
 
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  • #12
If the universe is expanding then to look back in time, via distance, would be to see a smaller universe. But we don't! The further back in time we look, the larger it can be seen to have been. To expand to a diameter of at least 24 B.L.Ys. in only 1.7 B.Ys. would seem to me to be a problem with our picture of the universe and its evolution.
 
  • #13
Peter Watkins said:
If the universe is expanding then to look back in time, via distance, would be to see a smaller universe. But we don't! The further back in time we look, the larger it can be seen to have been. To expand to a diameter of at least 24 B.L.Ys. in only 1.7 B.Ys. would seem to me to be a problem with our picture of the universe and its evolution.
No, it's a problem with your understanding of cosmology. What exactly do you mean by "The further back in time we look, the larger it can be seen to have been." What specific cosmological observation are you referring to here? To calculate the distance to the edge of the observable universe (the particle horizon, d_H), one must compute the integral
d_H = a(t)\int_0^{t_0} \frac{dt'}{a(t')}
where a(t) is the scale factor of the universe and t_0 is the present time. It's not a matter of simply multiplying the age of the universe by the speed of light, since that assumes a static universe (the point I made earlier that you decided to ignore). See this FAQ for more information,
http://http://www.astro.ucla.edu/~wright/cosmology_faq.html#DN"

There's plenty about this on wikipedia as well: http://http://en.wikipedia.org/wiki/Observable_universe"
 
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  • #14
How on Earth is the original question ignoring the expansion of the universe?
 
  • #15
Peter Watkins said:
If the universe is expanding then to look back in time, via distance, would be to see a smaller universe. But we don't! ...

I have to go to a family get-together today but when I get back I want to try something, Peter. I am going to take a different tack and interpret every question of yours as thoughtful, well-motivated, and intelligent. I'm going to assume that all the critical reaction to your questions is due to a purely verbal misunderstanding (on one side or the other). It could just be due to a mismatch of verbal concepts.

When we look back in time the OU (the matter we see now out to the surface of last scattering) was actually much smaller---radius about 41 million LY, if you could have frozen it back then at the time it emitted the light.

It is NOW radius about 45.6 billion LY. Having expanded about 1100-fold.

You can get that from the Morgan calculator. I have a dim memory of your telling me you had "been there done that" with her "cosmos calculator". Is that right? You have spent some time playing around with it?

So it should be clear that what we see when we look back IS much smaller.

And the physics we see is of something that small, with the hot gas that dense, so that we can see even evidence of sound waves that were traveling thru it at that moment.

So you may find that reassuring. You seemed worried that we look back the OU is very large. No, what we see back then is small and is evidently behaving as a relatively small hot concentrated gas world. We see its image in the sky and measure its temperature. As it was back then.

But I have to go. When I get back I will try to reassure some of your worries. In the meanwhile I hope you hang in there and listen to the criticism cheerfully. It is well-informed and well-intended, for sure.

And there may be issues of substance (not just semantics) that do call for critical attention.
Anyway, I'll check in later.

OOPS I just saw your name crossed out. Well that's that. It was probably inevitable :smile:
 
  • #16
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  • #17
Bill, is this what you're after ?

http://metaresearch.org/cosmology/BB-top-30.asp
 
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