No, the Universe is not expanding at an accelerated rate...

Awesome and detailed real answer, paddoboy. I'm very impressed.

It may take a very long amount of time to sort out whether something so large is rotating or not with a a local instrument like a gyroscope or the equivalent of a Foucault pendulum, or even the entire solar system, but your answer is still golden.

Still not buying into the stretching of space FTL in this era after the BB though. It changes the isotropy of space itself. There would be consequences you could easily see, and not just red shifts. It would screw up gravitational lensing everywhere it happens. Does it?

 

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I'm sure if you were a mind to, you could find much more, throwing light on the subject: My computer skills are very basic being an old bastard.

Why? I would suggest wherever gravitational lensing was occuring, the local mass/energy density, hence gravity, would be overcoming the expansion.

 

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ignoring the inflation period. No bit of space is expanding FTL. space, on large scales and outside of gravitationally bound regions, is expanding, at 72km/s/per megaparsec. (from memory). it is only that added up over billions of lightyears it appears to expand FTL to us. You could use the horrible balloon analogy to see this if you want.

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https://blogs.scientificamerican.co...-haven-t-decided-dark-energy-is-nonexistent/#


No, Astronomers Haven't Decided Dark Energy Is Nonexistent
You might have read otherwise in some headlines lately, but don't be misled


This week, a number of media outlets have put out headlines like "The universe is expanding at an accelerating rate, or is it?” and “The Universe Is Expanding But Not At An Accelerating Rate New Research Debunks Nobel Prize Theory.” This excitement is due to a paper just published in Nature’s Scientific Reportscalled "Marginal evidence for cosmic acceleration from Type Ia supernovae,” by Nielsen, Guffanti and Sarkar.

Once you read the article, however, it’s safe to say there is no need to revise our present understanding of the universe. All the paper does is slightly reduce our certainty in what we know—and then only by discarding most of the cosmological data on which our understanding is based. It also ignores important details in the data it does consider. And even if you leave aside these issues, the headlines are wrong anyway. The study concluded that we’re now only 99.7 percent sure that the universe is accelerating, which is hardly the same as “it’s not accelerating.”

The initial discovery that the universe is expanding at an accelerating rate was made by two teams of astronomers in 1998 using Type Ia Supernovae as cosmic measuring tools. Supernovae—exploding stars—are some of the most powerful blasts in the entire cosmos, roughly equivalent to a billion-billion-billion atomic bombs exploding at once. Type Ia’s are a special kind of supernova in that, unlike other supernovae, they all explode with just about the same luminosity every time likely due to a critical mass limit. This similarity means that the differences in their observed brightness are almost entirely based on how far away they are. This makes them ideal for measuring cosmic distances. Furthermore, these objects are relatively common, and they are so bright that we can see them billions of light years away. This shows us how the universe appeared billions of years ago, which we can compare to how it looks today.

These supernovae are often called “standard candles” for their consistency, but they’re more accurately “standardizable candles,” because in practice, their precision and accuracy can be improved still further by accounting for small differences in their explosions by observing how long the explosion takes to unfold and how the color of the supernovae are reddened by dust between them and us. Finding a way to do these corrections robustly was what led to the discovery of the accelerating universe. .

The recent paper that has generated headlines used a catalog of Type Ia supernovae collected by the community (including us) which has been analyzed numerous times before. But the authors used a different method of implementing the corrections—and we believe this undercuts the accuracy of their results. They assume that the mean properties of supernovae from each of the samples used to measure the expansion history are the same, even though they have been shown to be different and past analyses have accounted for these differences. However, even ignoring these differences, the authors still find that there is roughly a 99.7 percent chance that the universe is accelerating—very different from what the headlines suggest.



THE COSMIC MICROWAVE BACKGROUND RADIATION, EMITTED A FEW HUNDRED THOUSAND YEARS AFTER THE BIG BANG, PROVIDES AN INDEPENDENT LINE OF EVIDENCE FOR THE ACCELERATING UNIVERSE. CREDIT: NASA/WMAP SCIENCE TEAM VIA WIKIMEDIA COMMONS
Furthermore, the overwhelming confidence astronomers have that the universe is expanding faster now than it was billions of years ago is based on much more than just supernova measurements. These include tiny fluctuations in the pattern of relic heat after the Big Bang (i.e., the cosmic microwave background) and the modern day imprint of those fluctuations in the distribution of galaxies around us (called baryon acoustic oscillations). The present study also ignores the presence of a substantial amount of matter in the Universe, confirmed numerous times and ways since the 1970’s, further reducing the study confidence. These other data show the universe to be accelerating independently from supernovae. If we combine the other observations with the supernova data, we go from 99.99 percent sure to 99.99999 percent sure. That’s pretty sure!

We now know that dark energy, which is what we believe causes the expansion of the universe to accelerate, makes up 70 percent of the universe, with matter constituting the rest. The nature of dark energy is still one of the largest mysteries of all of astrophysics. But there has been no active debate about whether dark energy exists and none about whether the universe is accelerating since this picture was cemented a decade ago.

There are now many new large surveys, both on the ground and in space, whose top priority over the next two decades is to figure out exactly what this dark energy could be. For now, we have to continue to improve our measurements and question our assumptions. While this recent paper does not disprove any theories, it is still good for everyone to pause for a second and remember how big the questions are that we are asking, how we reached the conclusions we have to date and how seriously we need to test each building block of our understanding.

 

http://www.forbes.com/sites/startsw...s-the-universe-not-accelerating/#6186951367ca


n 1998, the two leading independent collaborations working to measure distant supernovae in the Universe reported the same bizarre findings: they seemed to indicate that the Universe was accelerating. The only way to explain how distant these lights appeared was if the fabric of space was expanding at a rate that wasn’t decreasing like we’d expect, and if the most distant galaxies were receding faster and faster, despite the pull of gravity. Over the next 13 years, the evidence grew stronger and stronger for this picture, and in 2011 three pioneers in the field were awarded the Nobel Prize. And then, just last week, a new study came out alleging that the supernova evidence for this picture was marginal at best. The study concludes that perhaps the Universe hasn’t been accelerating, after all.

But is that fair and correct? Certainly the news reports are claiming it is, but what does the science say? Let’s start with what the supernova data is, and what it’s told us so far.

more at link:

 

Basically the articles are saying that much other data still shows the universe to have the DE component [CC?] and that the acceleration is still occurring, and that much refinement and research still needs to be done.

 

from the previous link
extract:

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Measuring back in time and distance (to the left of “today”) can inform how the Universe will evolve and accelerate/decelerate far into the future. Image credit: Saul Perlmutter of Berkeley, via http://newscenter.lbl.gov/2009/10/27/evolving-dark-energy/.



Oftentimes, it takes fresh eyes to approach a problem differently from how everyone else is approaching it. In their Scientific Reportspaper out just a few days ago, scientists Nielsen, Guffanti and Sarkar — all of whom don’t specialize in supernova studies – did exactly that. Here’s what their results indicate.

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The figure representing the confidence in accelerated expansion and in the measurement of dark energy (y-axis) and matter (x-axis) from supernovae alone. Image credit: Nielsen, Guffanti and Sarkar, 2016, from the preprint at https://arxiv.org/pdf/1506.01354v3.pdf.


Even if all of the supernova data were thrown out and ignored, we have more than enough evidence at present to be extremely confident that the Universe is accelerating, and made of about 2/3 dark energy.

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The supernova data from the sample used in Nielsen, Guffati and Sarkar cannot distinguish at 5-sigma between an empty Universe (green) and the standard, accelerating Universe (purple), but other sources of information matter as well. Image credit: Ned Wright, based on the latest data from Betoule et al. (2014), via http://www.astro.ucla.edu/~wright/sne_cosmology.html.

 

http://phys.org/news/2016-10-expansion-universe.html

Relax, the expansion of the universe is still accelerating
October 28, 2016 by Tamara Davis, The Conversation


extract:

So why does this new paper claim that the detection of acceleration is "marginal?"

Well, it is marginal if you only use a single data set. After all, most big discoveries are initially marginal. If they were more obvious, they would have been discovered sooner.

The evidence, so far

The supernova data alone could, at only a slight stretch, be consistent with a universe that neither accelerates nor decelerates. This has been known since the original discovery, and is not under dispute.

But if you also add one more piece of information - for example, that matter exists - then there's nothing marginal about it. New physics is clearly required.

In fact, if the universe didn't accelerate or decelerate at all, which is an old proposal revisited in this new paper, new physics would still be required.

These days the important point is that if you take all of the supernova data and throw it in the bin, we still have ample evidence that the universe's expansion accelerates.

For example, in Australia we did a project called WiggleZ, which over five years made a survey of the positions of almost a quarter of a million galaxies.

The pattern of galaxies isn't actually random, so we used this pattern to effectively lay grid paper over the universe and measure how its size changes with time.

Using this data alone shows the expanding universe is accelerating, and it is independent of any supernova information. The Nobel Prize was awarded only after this and many other observational techniques confirmed the supernova findings.

http://phys.org/news/2016-10-expansion-universe.html

 

https://arxiv.org/pdf/1404.7266v1.pdf

Cosmological constraints on dark energy
Tamara M. Davis:

Abstract:
It has been only ∼15 years since the discovery of dark energy (although some may argue there were strong indications even earlier). In the short time since measurements of type Ia supernovae indicated an accelerating universe, many other techniques have now confirmed the acceleration is real. The variety of ways in which dark energy has been confirmed is one of the reasons we are so confident in the statement that most of the energy in the universe is in a form we can not see except through its gravitational influence. This review aims to summarise briefly the many varied ways we now have measured dark energy. The fact that these different techniques all indicate that the simplest model remains the best – that dark energy contributes a constant background acceleration – is remarkable, since each of these different types of measurements represented opportunities for this simplest model to fail. Although we currently lack a compelling theoretical explanation for this acceleration, any explanation will have to explain the wide variety of complementary observations that we review here. This is an informal presentation, following the lines of the talk I presented at the General Relativity and Gravitation (GR20) conference in Warsaw in July 2013.

 

5 years survey of galaxy means the maximum distance travelled by the galaxy away which could be just recorded would be 5 light years. The point is do we have a galaxy where positional accuracy is within +/- 5 light years? So this survey has an unanswered question.

I have proposed a simple concept that gravity is effectively due to stretching of space, maths is being worked out but it does not require extensive tensor analysis to establish that total stretching between two objects (earth as observer and remote galaxy) is directly proportional to distance between these objects. Farther the galaxy, higher the total stretching, thus higher the observed Red Shift.

All recorded observations can be explained under this proposal and it does not require Dark Matter, Dark Energy etc.

 

If you read the link/s, you will find many observations that support an accelerating expansion rate, that still stands firm, despite this article/paper in the OP.

Your proposal/s are invalid until and unless you off er evidence supporting them, or evidence invalidating the status quo at this time.
You also supported a totally fabricated Black Neutron Star concept, with the same lack of substance.

 

So your argument is that existing ideas are able to explain all the observation and hence cannot be dismissed. I agree with you on this premise, but it requires Dark Matter to explain certain observations and Dark Energy to explain accelerated expansion. There are controversies and questions around both these aspects.

On the other hand, the proposal by me explains these observations and all other observations without invoking DM and DE.

 

DM has been evidenced and explained in many papers, some of which I have listed here.

So you say.

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You shouldn't have much trouble getting it properly peer reviewed then, OK?

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You have badly misinterpreted the meaning of the sentence in #28:

Can you think of an alternate way to understand what that meant? Nothing whatsoever to do with the hopeless task of trying to measure changes in relative position of a given galaxy over 5 years! A galaxy that typically spans ~ 10^5 ly in size!

 

I do not dispute your listed papers. The point is, DM will always remain a mystery, it cannot be unveiled fully even if we get some indirect detection.

On the question of getting it peer reviewed, I need to work out the full maths, most likely I will not succeed in developing the precise maths, so I have to present this as theoretical work sans detailed maths. I am closing certain loose points, but it is able to explain strong nuclear interaction to very high red shifts observed.

 

Not necessarily. Perhaps you would like to tell the forum why you think it will always remain a mystery.

Best of luck!

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If this survey talks of anything beyond redshift to prove accelerated expansion, then I cannot think of any alternate way. You already concur with me that +/- 5 ly is a hopeless resolution for such large distances so that cannot be the stand.

 

Yes, anything which despite being present in such huge quantity, if cannot be seen and only its gravitational effect is observed, then such thing will always remain mysterious.

Thank you for wishing me luck.

 

Here you go: https://wigglez.swin.edu.au/site/
Still no fee for my services.

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I am sticking to accelerated expansion. The data as recorded over such period is not futile, that can be used for many more ideas, but I inferred that this data set is being exclusively pushed to side with accelerated expansion.