Free Republic
Browse · Search
General/Chat
Topics · Post Article

Skip to comments.

No, the Universe is not expanding at an accelerated rate, say physicists
Science alert ^ | 10/24/16 | BEC CREW

Posted on 10/24/2016 1:58:12 PM PDT by LibWhacker

This could change everything.

Back in 2011, three astronomers were awarded the Nobel Prize in Physics for their discovery that the Universe wasn’t just expanding - it was expanding at an accelerating rate.

The discovery led to the widespread acceptance of the idea that our Universe is dominated by a mysterious force called dark energy, and altered the standard model of cosmology forever. But now physicists say this discovery might have been false, and they have a much larger dataset to back them up.

For a bit of background on the 2011 Nobel Prize in Physics, it was shared between cosmologists Saul Perlmutter from the University of California, Berkeley; Adam Riess from Johns Hopkins University; and Brian Schmidt from the Australian National University.

During the 1990s, these three scientists were part of competing teams that were measuring distant Type 1a supernovae - the violent end of a type of star called a white dwarf.

White dwarf stars are made from one of the densest forms of matter in the known Universe - surpassed only by neutron stars and black holes.

While a typical white dwarf will only be slightly larger than Earth, it will have around the same amount of mass as our Sun. To put that into perspective, you could fit roughly 1,300,000 Earths inside the Sun.

Now imagine that incredibly dense, dead star collapsing under the weight of its own gravity. We’re talking about a luminosity level that’s about 5 billion times brighter than the Sun.

Because each Type 1a supernova explodes with roughly the same brightness, the amount of light they give off can be used as an indication of their distance from Earth - and slight shifts in colour can also be used to figure out how fast they’re moving.

When Perlmutter, Riess, and Schmidt measured all the data for known Type 1a supernovae, recorded by the Hubble space telescope and a number of large ground-based telescopes, they found something incredibly strange.

As the Royal Swedish Academy explained on the morning of the Nobel Prize announcement in Stockholm:

"In a Universe which is dominated by matter, one would expect gravity eventually should make the expansion slow down. Imagine then the utter astonishment when two groups of scientists ... discovered that the expansion was not slowing down, it was actually accelerating.

By comparing the brightness of distant, far-away supernovae with the brightness of nearby supernovae, the scientists discovered that the far-away supernovae were about 25 percent too faint. They were too far away. The Universe was accelerating. And so this discovery is fundamental and a milestone for cosmology. And a challenge for generations of scientists to come."

The find was backed up by data collected separately on things like clustering galaxies and the cosmic microwave background - the faint afterglow of the Big Bang.

And earlier this year, NASA and ESA scientists found that the Universe could be expanding around 8 percent faster than originally thought.

By all accounts, the discovery was a solid one (Nobel Prize solid) but it posed a very difficult question - if the collective gravity from all the matter expelled into the Universe by the Big Bang has been slowing everything down, how can it be accelerating?

As Brendan Cole reported for us in May:

"There’s something pervading the Universe that physically spreads space apart faster than gravity can pull things together. The effect is small - it’s only noticeable when you look at far-away galaxies - but it’s there. It’s become known as dark energy - 'dark', because no one knows what it is."

Since scientists first proposed dark energy, no one's gotten any closer to figuring out what it could actually be.

But now an international team of physicists from institutions say don't worry about it, because it probably doesn't even exist, and they've got a much bigger database of Type 1a supernovae to back them up.

By applying a different analytical model to the 740 Type Ia supernovae that have been identified so far, the team says they've been able to account for the subtle differences between them like never before.

They say the statistical techniques used by the original team were too simplistic, and were based on a model devised in the 1930s, which can't reliability be applied to the growing supernova dataset.

They also mention that the cosmic microwave background isn't directly affected by dark matter, so only serves as an "indirect" type of evidence.

"We analysed the latest catalogue of 740 Type Ia supernovae - over 10 times bigger than the original samples on which the discovery claim was based - and found that the evidence for accelerated expansion is, at most, what physicists call '3 sigma'," reports lead researcher, Subir Sarkar, from the University of Oxford.

"This is far short of the '5 sigma' standard required to claim a discovery of fundamental significance."

Instead of finding evidence to support the accelerated expansion of the Universe, Sarkar and his team say it looks like the Universe is expanding at a constant rate. If that's truly the case, it means we don't need dark energy to explain it.

"A more sophisticated theoretical framework accounting for the observation that the Universe is not exactly homogeneous, and that its matter content may not behave as an ideal gas - two key assumptions of standard cosmology - may well be able to account for all observations without requiring dark energy," he says.

Now, to be clear, this is just one study, and it's a big, extremely controversial claim that a Nobel Prize-winning discovery is fundamentally wrong. (Because I don't have to tell you that Nobel Prizes aren't given out lightly.)

But replication of results is everything in science, and if we have a larger dataset to go on than we did five years ago, we should use it to support - or correct - previous discoveries.

The question now is whether Sarkar's team applied their new statistical model to the data in a way that best reflects the science, and it will likely spur on a whole lot of physicists to figure out which is right - accelerating Universe, or constant Universe.

"Naturally, a lot of work will be necessary to convince the physics community of this, but our work serves to demonstrate that a key pillar of the standard cosmological model is rather shaky," says Sarkar.

"Hopefully, this will motivate better analyses of cosmological data, as well as inspiring theorists to investigate more nuanced cosmological models."

The research has been published in Scientific Reports.


TOPICS: Astronomy; Science
KEYWORDS: accelerating; dark; energy; expanding; universe
Navigation: use the links below to view more comments.
first 1-2021-4041-6061-65 next last

1 posted on 10/24/2016 1:58:12 PM PDT by LibWhacker
[ Post Reply | Private Reply | View Replies]

To: LibWhacker

Science is filled with phlogiston.


2 posted on 10/24/2016 2:01:08 PM PDT by aMorePerfectUnion
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

#UniverseExpansionMatters


3 posted on 10/24/2016 2:01:58 PM PDT by freedumb2003 (Never Trump=Always hiLIARy)
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

the DarkEnergy is everywhere and it knows the scientists were uncovering it
so
its gone into deeper hiding.

DeeperDark.
new comics action hero

(will be announced TransSexual in issue No. 2)


4 posted on 10/24/2016 2:02:18 PM PDT by faithhopecharity ("Politicians are not born. They're excreted." Marcus Tullius Cicero.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: aMorePerfectUnion

Scientists can’t even get their $h1t together and expect us to just follow along. Oh, I thought this was a global warming thread. Sorry, carry on with the theoretical pointless physics.


5 posted on 10/24/2016 2:02:20 PM PDT by sagar
[ Post Reply | Private Reply | To 2 | View Replies]

To: LibWhacker

The Democrat Klingons are controlling the universe now.


6 posted on 10/24/2016 2:02:56 PM PDT by EagleUSA
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

I thought it was “settled science.”


7 posted on 10/24/2016 2:03:23 PM PDT by Fido969
[ Post Reply | Private Reply | To 1 | View Replies]

To: aMorePerfectUnion
Let me save everyone some time:

phlo·gis·ton /flōˈjistän,-tən/

noun

a substance supposed by 18th-century chemists to exist in all combustible bodies, and to be released in combustion.

8 posted on 10/24/2016 2:03:53 PM PDT by freedumb2003 (Never Trump=Always hiLIARy)
[ Post Reply | Private Reply | To 2 | View Replies]

To: LibWhacker
Back in 2011, three astronomers were awarded the Nobel Prize in Physics

Who on earth has been giving out the Nobel prizes lately?

9 posted on 10/24/2016 2:04:15 PM PDT by Fido969
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

Bush’s fault. Make ‘em pay back the prize money.


10 posted on 10/24/2016 2:05:37 PM PDT by beethovenfan (I always try to maximize my carbon footprint.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker
Of course not....not now.
Now it's stopped.
Soon it will contract

"ISA 34:4 And all the host of heaven shall be dissolved, and the heavens shall be rolled together as a scroll: and all their host shall fall down, as the leaf falleth off from the vine, and as a falling fig from the fig tree."
"Rev 6:14 And the heaven departed as a scroll when it is rolled together; and every mountain and island were moved out of their places."

11 posted on 10/24/2016 2:05:49 PM PDT by DannyTN
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

Yet another countless example,why science is not about,
consensus. And why we should not put our faith in it,100% at any given time, and not ever cut off debate about other theories and data that doesnt match preconceived notions.


12 posted on 10/24/2016 2:05:58 PM PDT by Secret Agent Man (Gone Galt; Not averse to Going Bronson.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

Does this mean that the type 1A super nova is NOT the standard candle they think it is??

Sheldon Cooper on ‘Big Bang Theory’ will probably be ranking out Perlmutter again in an upcoming episode.


13 posted on 10/24/2016 2:06:13 PM PDT by Vaquero ( Don't pick a fight with an old guy. If he is too old to fight, he'll just kill you.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: EagleUSA

If Klingons were real and around today...they would be many things...none of those things would be democrats.

They values honor.


14 posted on 10/24/2016 2:08:23 PM PDT by Vaquero ( Don't pick a fight with an old guy. If he is too old to fight, he'll just kill you.)
[ Post Reply | Private Reply | To 6 | View Replies]

If the universe was imploding, wouldn’t things closer to the “Center of the Universe” appear to be accelerating away from us, just as objects farther away from the “Center of the Universe” would also appear to be accelerating away from us? From our reference point, I would think the universe exploding or imploding would look about the same.


15 posted on 10/24/2016 2:10:16 PM PDT by dsrtsage (One half of all people have below average IQ. In the US the number is 54%)
[ Post Reply | Private Reply | To 13 | View Replies]

To: LibWhacker

> “They say the statistical techniques used by the original team were too simplistic, and were based on a model devised in the 1930s, which can’t reliability be applied to the growing supernova dataset.”

ALL MODELS ARE FALSE; SOME ARE USEFUL.


16 posted on 10/24/2016 2:10:54 PM PDT by Hostage (ARTICLE V):)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Fido969

Two questions arise:
1. will the 2011 Nobel recipients have to repay their prize money?
2. will this new team and their supporters be labeled “dark matter deniers”?


17 posted on 10/24/2016 2:14:24 PM PDT by jonno (Having an opinion is not the same as having the answer...)
[ Post Reply | Private Reply | To 7 | View Replies]

To: LibWhacker

Like Global Warming, the Consensus was wrong?


18 posted on 10/24/2016 2:16:36 PM PDT by Uncle Miltie ("BECAUSE YOU'D BE IN JAIL")
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

Sure, and what is the weather going to be next month? Tomorrow?

Thought so.


19 posted on 10/24/2016 2:16:50 PM PDT by faucetman (Just the facts, ma'am, Just the facts ,)
[ Post Reply | Private Reply | To 1 | View Replies]

To: LibWhacker

We are now in what physicists call the “Millennial” phase of the Universe, its pretty pretty much not doing anything.


20 posted on 10/24/2016 2:17:11 PM PDT by heights
[ Post Reply | Private Reply | To 1 | View Replies]


Navigation: use the links below to view more comments.
first 1-2021-4041-6061-65 next last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
General/Chat
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson