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I finally found an accurate article on the speed of universal expansion


Angelo

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https://www.space.com/hubble-constant-crisis-deepens.html

See it takes a bigger man to say "I do not know" than it does to know the unknowable

No One Can Agree How Fast Universe Is Expanding. New Measure Makes Things Worse.

By Adam Mann 2020-01-09T20:37:47Z

We just might need new physics to get out of this mess.

 

HONOLULU — A crisis in physics may have just gotten deeper. By looking at how the light from distant bright objects is bent, researchers have increased the discrepancy between different methods for calculating the expansion rate of the universe

"The measurements are consistent with indicating a crisis in cosmology," Geoff Chih-Fan Chen, a cosmologist at the University of California, Davis, said here during a news briefing on Wednesday (Jan. 8) at the 235th meeting of the American Astronomical Society in Honolulu.

 

At issue is a number known as the Hubble constant. It was first calculated by American astronomer Edwin Hubble nearly a century ago, after he realized that every galaxy in the universe was zipping away from Earth at a rate proportional to that galaxy's distance from our planet. 

...

The problem is that, in recent years, different teams have disagreed over what exactly this constant's value is. Measurements made using the cosmic microwave background (CMB), a remnant from the Big Bang that provides a snapshot of the infant universe, suggest that the Hubble constant is 46,200 mph per million light-years (or, using cosmologists' units, 67.4 kilometers/second per megaparsec).

But by looking at pulsating stars known as Cepheid variables, a different group of astronomers has calculated the Hubble constant to be 50,400 mph per million light-years (73.4 km/s/Mpc). 

The discrepancy seems small, but there is no overlap between the independent values and neither side has been willing to concede major mistakes in its methodology. 

 

 

So whatever you know...……………..it's wrong, when you know that you are right

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3 minutes ago, Angelo said:

See it takes a bigger man to say "I do not know" than it does to know the unknowable

There is no doubt the universe is expanding the question what exactly the rate is.  The more interesting question is why the to methods give a differ number.

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7 minutes ago, Bufofrog said:

There is no doubt the universe is expanding the question what exactly the rate is.  The more interesting question is why the to methods give a differ number.

It would help if we actually knew what the universe was

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6 minutes ago, Angelo said:

It would help if we actually knew what the universe was

No. It wouldn’t. We don’t need to know, for example, what a specific rare fish is in order to measure it’s speed. 

Edited by iNow
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3 minutes ago, iNow said:

No. It wouldn’t. We don’t need to know, for example, what a specific rare fish is in order to measure it’s speed. 

You would know it's a fish, in water exposed to 1G and you would be close enough to monitor it, and it would not be moving in excess of 3 billion miles per hour or more, in an unknown medium

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12 minutes ago, iNow said:

Also irrelevant 

LOL Sagan said that science was over, that the pace of learning would drastically slow because basically everything had been discovered.

Intel ignored Sagan, as are computer engineers today.  Sagan was as wrong as wrong could possibly be as 99.999 percent of all knowledge is still unknown and may always be as we can not see outside the universe to achieve the perspective on what it is.

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We are able to measure distances of tens of billions of light years, the brightness of variable stars at those distances, and recession speeds of galaxies at those distances, with less than 10 % error.

And you think that means we don't know what the universe is and need to scrap current cosmological models in favor of 'new Physics" ?

Despite people's best efforts, you have learned nothing in the last few days.

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8 hours ago, Angelo said:

It would help if we actually knew what the universe was

Therefor scientists (cosmologists with computer programmers together) are making simulations...

1) change code of simulation.

2) change constants and/or variables.

3) rerun simulation on supercomputer cluster .

4) compare results of simulation with results from Hubble and other telescopes.

 

The example of delay of photons travelling from supernova versus neutrinos (which arrive hours or minutes earlier) suggest that similar delay should be from light from distant galaxies. I would start from placing these delays on graph with distance to supernova (measured different methods) to check how delay varies with distance. If data will be consistent later it could be used as method of estimation of distance to supernova just from delay.

Edited by Sensei
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8 hours ago, Angelo said:

See it takes a bigger man to say "I do not know" than it does to know the unknowable

Actually, that article is about making more accurate measurements; ie. about knowing more.

So, yes, this may show up something new that we don't know about. This sort of "crisis" is why science is so exciting; it may indicate a new discovery. One the other hand, it might just be down to some sort of error in one of the measurements.

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1 hour ago, swansont said:
!

Moderator Note

Please do not post articles in their entirety. That violates copyright rules.

 

When I do not post the article I am accused of copyright infringement.  Now do you agree or disagree with the article, remembering that if you disagree that you know more than the entire rest of the science community combined.

2 hours ago, Strange said:

Actually, that article is about making more accurate measurements; ie. about knowing more.

So, yes, this may show up something new that we don't know about. This sort of "crisis" is why science is so exciting; it may indicate a new discovery. One the other hand, it might just be down to some sort of error in one of the measurements.

Actually the article is about the newest most accurate measurement that invalidates physics as it is currently known.  This is the crisis referred to

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57 minutes ago, Angelo said:

This is the crisis referred to

Media journalists abuse words like "crisis" to have catchy title for an article, so people will visit and read their article. It is similar to the words "professional", and "intelligent" in advertising materials. Just yet another clickbait.

https://en.wikipedia.org/wiki/Clickbait

 

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You know it's always a foolish policy to trust pop media coverage of two studies. You always get led down garden paths.

The two datasets use different regions and methodologies to determine the rate of expansion. This is part of the reason for the discrepancy but that link does not mention further research showing that our local group may be in an underdense region that is throwing off the two datasets.

 This is part of the scientific method you collect data do the calculations and when you find a discrepancy you look for a cause.

Quite frankly the error margin is no great crisis that requires any new physics.

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59 minutes ago, Angelo said:

Now do you agree or disagree with the article, remembering that if you disagree that you know more than the entire rest of the science community combined.

It s a news story, reporting on scientific research. What would "disagree with the article" mean? That the journalist made up the story and no such research has taken place.

I have seen the same research reported in multiple places so I the article appears to be accurate.

1 hour ago, Angelo said:

Actually the article is about the newest most accurate measurement that invalidates physics as it is currently known. 

Where does it say that it invalidates physics as it is currently known?

It says that two different measurements, which were expected to give the same result, provide different results. This is intriguing and tells us that something is wrong with the measurements or that our model of the universe needs to be adjusted (or both). Further work may tell us which. That is how science works.

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Funny part is about the only cosmology calculation the discrepancy would have a noticeable effect would be calculating the age of the universe. The discrepancy has no appreciable effect on our distance measurements or any other LCDM formula.

On the age of the universe calculation it works out to less than 10,000 years difference thereabouts. Which quite frankly is a miniscule amount and calculating the age of the universe has always had similar error margins.

Nothing that requires any new physics nor shows LCDM needs to change any single formula.

Edited by Mordred
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15 hours ago, iNow said:

He’s just pathetically trying and failing to get a rise out of us

I have to say, over the years, the mainstream deniers have given me the impression that it's less about poking at the establishment and more about the superiority they feel when they discover they don't have to actually study it if they can ridicule it, claiming it isn't worth it. Science is a LOT of work.

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