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Bmpbmp1975

Expansion different in different directions

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Posted (edited)

Dumbing down the explanation so as to make it more understandable to your audience, only gets you so far.
The audience itself, has to make some 'effort' to understand, by asking the right questions, filling in the 'holes' in their understanding if you will.
We all had the same teachers as 20-25 other people, in school, yet some learned more and some learned less.
IOW some put in more effort, and some less ( or no ) effort.
( I, myself, was accused, by Dr. G Kidson, in Uni, of being a 'coaster', and not putting in enough effort )

 

Edited by MigL

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6 minutes ago, Bmpbmp1975 said:

I don't think you understand how science works.

Some people made some measurements. They suggested one reason for the data could be that the universe was not expanding at the same rate in all directions. If you read the paper again, they also pointed out that there are several other possible explanations.

Ethan's article is pointing out that these other existing explanations are more likely to be the case. In particular, he casts doubt on their assumption of a tight relationship between temperature and luminosity (as I pointed out when I posted that link before).

Note that science is all about possibilities and what seems to be most consistent with the evidence. It is not about truth. And not all scientists agree about what the best explanations are.

From the article linked from your second link:

  • This finding could be a sign that the universe is actually “anisotropic” ...
  • This possible evidence for anisotropy ...
  • Doing so allowed the researchers to estimate the cluster’s x-ray luminosity—and therefore its distance
  • allowed Migkas and his colleagues to probe potential deviations in the universe’s rate of expansion
  • thus potentially closer or farther away than expected
  • "We managed to pinpoint a region that seems to expand slower than the rest of the universe and one that seems to expand faster,” Migkas says
  • Therefore, the situation is still vague.
  • Perhaps, somewhere in the intervening eons
  • Alternatively, the universe might not be lopsided at all
  • The most obvious explanation, of course, would be that the apparent asymmetries in cluster spacing are because of flaws in the data or their analysis
  • Such inconsistencies suggest correlations between a galaxy cluster’s x-ray temperature and its luminosity are not as clear-cut as researchers would prefer
  • there are other potential problems to deal with
  • Riess adds. “That seems suspicious!”
  • David Spergel ... also suspects faults in the cluster-based measurements
  • “This is a paper that is very important if [it is] true but very unlikely to be true,” he says.
  • They are now looking for further hints of galaxy-cluster anisotropy
  • It would be great if we knew

https://www.scientificamerican.com/article/do-we-live-in-a-lopsided-universe1/

Do you get the idea? Nothing is certain, everything is conditional, it all needs further research,

 

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Posted (edited)
26 minutes ago, Bmpbmp1975 said:

don’t get it, how did they change there minds within days?

The first article states: 

Quote

In this particular case, there is some preliminary evidence that galaxy clusters may be exhibiting different properties in some directions versus others, and that’s interesting. Whether it’s because of the method used, the data taken and analyzed, or actual motions through the Universe will be a question best answered by more and better science throughout the 2020s. But it most definitely cannot be because the Universe is expanding differently in different directions. Already, for multiple decades, the evidence has been good enough to completely rule that possibility out.

(emphasis mine) Source: https://www.forbes.com/sites/startswithabang/2020/04/21/no-the-universe-cannot-be-expanding-differently-in-different-directions/amp/


So evidence already available rules out different expansion in different direction. 
As @Strange told above, "This possible evidence for anisotropy". But that possibility turned out to be ruled out due to other evidence available. And since that evidence was already available it was a fast process. 

 

Edited by Ghideon
x-post w Strange, clarified

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2 minutes ago, Strange said:

I don't think you understand how science works.

Some people made some measurements. They suggested one reason for the data could be that the universe was not expanding at the same rate in all directions. If you read the paper again, they also pointed out that there are several other possible explanations.

Ethan's article is pointing out that these other existing explanations are more likely to be the case. In particular, he casts doubt on their assumption of a tight relationship between temperature and luminosity (as I pointed out when I posted that link before).

Note that science is all about possibilities and what seems to be most consistent with the evidence. It is not about truth. And not all scientists agree about what the best explanations are.

From the article linked from your second link:

  • This finding could be a sign that the universe is actually “anisotropic” ...
  • This possible evidence for anisotropy ...
  • Doing so allowed the researchers to estimate the cluster’s x-ray luminosity—and therefore its distance
  • allowed Migkas and his colleagues to probe potential deviations in the universe’s rate of expansion
  • thus potentially closer or farther away than expected
  • "We managed to pinpoint a region that seems to expand slower than the rest of the universe and one that seems to expand faster,” Migkas says
  • Therefore, the situation is still vague.
  • Perhaps, somewhere in the intervening eons
  • Alternatively, the universe might not be lopsided at all
  • The most obvious explanation, of course, would be that the apparent asymmetries in cluster spacing are because of flaws in the data or their analysis
  • Such inconsistencies suggest correlations between a galaxy cluster’s x-ray temperature and its luminosity are not as clear-cut as researchers would prefer
  • there are other potential problems to deal with
  • Riess adds. “That seems suspicious!”
  • David Spergel ... also suspects faults in the cluster-based measurements
  • “This is a paper that is very important if [it is] true but very unlikely to be true,” he says.
  • They are now looking for further hints of galaxy-cluster anisotropy
  • It would be great if we knew

https://www.scientificamerican.com/article/do-we-live-in-a-lopsided-universe1/

Do you get the idea? Nothing is certain, everything is conditional, it all needs further research,

 

I get it I am just more surprised it has been retracted so quickly within days 

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4 minutes ago, Bmpbmp1975 said:

I get it I am just more surprised it has been retracted so quickly within days 

It hasn't been retracted.

6 minutes ago, Ghideon said:

The first article states: 

(emphasis mine) Source: https://www.forbes.com/sites/startswithabang/2020/04/21/no-the-universe-cannot-be-expanding-differently-in-different-directions/amp/


So evidence already available rules out different expansion in different direction. 
As @Strange told above, "This possible evidence for anisotropy". But that possibility turned out to be ruled out due to other evidence available. And since that evidence was already available it was a fast process. 

I'm not sure I would say it is definitely ruled out. They are probably mistaken, but it is an interesting result that might still tell us something new.

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7 minutes ago, Bmpbmp1975 said:

I get it I am just more surprised it has been retracted so quickly within days 

One possible explanation turned out to be incorrect. Your source https://www.forbes.com/sites/startswithabang/2020/04/21/no-the-universe-cannot-be-expanding-differently-in-different-directions/amp/ also says:

Quote

In this particular case, there is some preliminary evidence that galaxy clusters may be exhibiting different properties in some directions versus others, and that’s interesting.

So there are many other possibilities to learn new stuff.

 

4 minutes ago, Strange said:

I'm not sure I would say it is definitely ruled out.

The following looked quite clear:

Quote

But it most definitely cannot be because the Universe is expanding differently in different directions. Already, for multiple decades, the evidence has been good enough to completely rule that possibility out.

But you are correct; it is not definitely ruled out. As always in science better observations may be done in the future.
Maybe a better statement? The results of this particular anisotropy measurement does not invalidate earlier CBR observations. Future research will explain the observed anisotropy or, less likely, confirm different expansion in different directions, possibly requiring modifications to current well established models. 

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No one has changed their minds or retracted anything.

The observations in question, while perfectly valid ( I would hope ), are limited, and do not allow for extrapolation to the universe as a whole.
The data set is too limited, and they clearly stated IF this applies to the whole Universe, THEN expansion is anisotropic.

Interesting article by the way.

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1 hour ago, Bmpbmp1975 said:

They aren’t the same people (hint: authors are listed) This is not people changing their minds.

And not within days. The paper was submitted last summer.

”Received: 29 August 2019 Accepted: 17 February 2020”

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On 4/12/2020 at 2:18 PM, Phi for All said:

I wouldn't word it quite this way. I think there are absolutely amazing scientists who have trouble dumbing complex knowledge down so the laymen understands. It's a special talent when one can relate knowledge that way, but I don't think science/scientists have any obligation to do so. Does a master carpenter have to be able to explain to a laymen what they're doing in order to build a magnificent home?

She does to some extent...if the layman is paying for the project.

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15 minutes ago, J.C.MacSwell said:

She does to some extent...if the layman is paying for the project.

So, are you agreeing with MigL, that the best scientists have to also be able to explain ("to some extent" is moving the goalposts, but whatever) what they do to a layman, because the laymen is paying for the project? Does the layman's money magically give them the ability to understand, or does the layman's understanding impact the work of "the best scientists"?

Perhaps I'm putting too much into MigL's definition of "explain". I don't think people who pay for someone else's expertise are required to understand what the expert is doing. Isn't that why they hired the expert? Perhaps the whole concept of listening to experts needs to be revisited, due to some spectacularly poor examples in recent years?

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Posted (edited)
1 hour ago, Phi for All said:

So, are you agreeing with MigL, that the best scientists have to also be able to explain ("to some extent" is moving the goalposts, but whatever) what they do to a layman, because the laymen is paying for the project? Does the layman's money magically give them the ability to understand, or does the layman's understanding impact the work of "the best scientists"?

Perhaps I'm putting too much into MigL's definition of "explain". I don't think people who pay for someone else's expertise are required to understand what the expert is doing. Isn't that why they hired the expert? Perhaps the whole concept of listening to experts needs to be revisited, due to some spectacularly poor examples in recent years?

I should have quoted more of your post. My comment was more with regard to the scientists "obligation".

On 4/12/2020 at 2:18 PM, Phi for All said:

I wouldn't word it quite this way. I think there are absolutely amazing scientists who have trouble dumbing complex knowledge down so the laymen understands. It's a special talent when one can relate knowledge that way, but I don't think science/scientists have any obligation to do so. Does a master carpenter have to be able to explain to a laymen what they're doing in order to build a magnificent home?

Some scientists, for example some of those publicly funded, have some obligation to relay their knowledge, to some extent, in a way the general public might understand.

(While of course some publicly funded scientists are obligated to keep it completely under wraps)

That said, I meant it more tongue in cheek than critical.

I agree with the gist of that post.

Edited by J.C.MacSwell

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Heeey,  how did I get dragged into this ?

3 hours ago, Phi for All said:

So, are you agreeing with MigL, that the best scientists have to also be able to explain ("to some extent" is moving the goalposts, but whatever) what they do to a layman, because the laymen is paying for the project?

What I actually said was...

On ‎4‎/‎12‎/‎2020 at 3:34 PM, MigL said:

Dumbing down the explanation so as to make it more understandable to your audience, only gets you so far.

I actually implied there is considerable onus on the audience ( layman ) to 'fill in the gaps' in his knowledge.
Learning is NOT an 'expert' disseminating knowledge, but a two way endeavor.
If only one of the two is trying, you get  'half-a*ssed' results.

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12 hours ago, MigL said:

Heeey,  how did I get dragged into this ?

I apologize! It was Airbrush I was quoting, not you. He made the claim that "the best scientists" need to be able to explain what they do to a laymen. My mistake on the quote.

And this was all in response to where the thread was headed in terms of explaining things to the OP. It was on topic at some point.

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No problem, Phi.

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1 hour ago, Phi for All said:

 "the best scientists" need to be able to explain what they do to a laymen. 

Lol then they complain when it comes to the math. Which is a primary factor. It takes considerable skill to dummy down any physics to the average layman.

 Particularly when the average layman doesn't know the rudimentary definitions. Good examples being mass, energy, dimension, degree of freedom, symmetry etc.

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17 minutes ago, Bmpbmp1975 said:

I am trying to understand if this article is talking about expansion rate different depending where we look or it is is something totally different?

https://www.miragenews.com/new-findings-reveal-universe-is-weirder-than-we-thought/

It is completely different. Nothing to do with expansion at all.

It is about measurements of something called the "fine structure constant". They get very slightly different results in one direction than another, for very distant galaxies.

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Sorry this quote threw me off 

So the universe may not be isotropic in its laws of physics – one that is the same, statistically, in all directions. But in fact, there could be some direction or preferred direction in the universe where the laws of physics change, but not in the perpendicular direction. In other words, the universe in some sense, has a dipole structure to it.

 

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3 minutes ago, Bmpbmp1975 said:

Sorry this quote threw me off 

So the universe may not be isotropic in its laws of physics – one that is the same, statistically, in all directions. But in fact, there could be some direction or preferred direction in the universe where the laws of physics change, but not in the perpendicular direction. In other words, the universe in some sense, has a dipole structure to it.

 

That is about the measurement of the fine structure constant getting different results in different directions (i.e. not being isotropic).

Quote

isotropic

adjective

Identical in all directions; invariant with respect to direction.
  1. (physics) Having properties that are identical in all directions; exhibiting isotropy.

https://www.yourdictionary.com/isotropic

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4 minutes ago, Strange said:

That is about the measurement of the fine structure constant getting different results in different directions (i.e. not being isotropic).

https://www.yourdictionary.com/isotropic

Thank you, still don’t get what the implications are if they are different 

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21 minutes ago, Bmpbmp1975 said:

Thank you, still don’t get what the implications are if they are different 

No implications for us. (It isn't coming to get you.)

But, if it turns out to be correct, then it may cause some bits of our theories of physics to change. The "fine structure constant" is assumed to be constant, as the name says. If it turns that it has changed very slightly, then we would need to modify theories to explain or incorporate that. It could, I suppose, make a slight difference to theories about the very, very early universe.

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Just now, Strange said:

No implications for us. (It isn't coming to get you.)

But, if it turns out to be correct, then it may cause some bits of our theories of physics to change. The "fine structure constant" is assumed to be constant, as the name says. If it turns that it has changed very slightly, then we would need to modify theories to explain or incorporate that. It could, I suppose, make a slight difference to theories about the very, very early universe.

I get it anytime something like this is found it could change our theories and possibly our text books and stuff 

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8 minutes ago, Bmpbmp1975 said:

I get it anytime something like this is found it could change our theories and possibly our text books and stuff 

It could. But most of time, exciting new discoveries fade away with more data.

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Just now, Strange said:

It could. But most of time, exciting new discoveries fade away with more data.

I think that this is something being looked at since 2018

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