# Seeking Evidence of Cosmological Inflation:

Discussion in 'Astronomy, Exobiology, & Cosmology' started by paddoboy, Apr 26, 2016.

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http://phys.org/news/2016-04-nasa-team-balloon-mission-evidence.html

NASA team set to fly balloon mission seeking evidence of cosmological inflation
April 26, 2016 by Lori Keesey

NASA scientist Al Kogut will search for evidence of cosmological inflation with a balloon-borne observatory called PIPER. Credit: NASA/W. Hrybyk
Now that scientists have confirmed the existence of gravitational waves, a NASA team is set to search for a predicted signature of primordial gravitational waves that would prove the infant universe expanded far faster than the speed of light and began growing exponentially almost instantaneously after the Big Bang.

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extract:
Although BICEP2 had observed a 400-square-degree patch of sky near the Milky Way's south pole—a region free of much of the dust that fills the star-studded disk—the telescope looked at only one frequency range. It tuned its instrument to 150 GHz, which is favorable for studies of the background radiation. To be truly cosmological in nature, however, the measurement should have been crosschecked at multiple frequencies.

In contrast, PIPER will observe the whole sky at four different frequencies—200, 270, 350, and 600 GHz—to discriminate between dust and primordial inflation, Kogut said. This assures that the team will be able to remove the dust signal.

Furthermore, PIPER will fly from a high-altitude scientific balloon to avoid emissions from Earth's atmosphere. If the gravitational waves exist, PIPER will detect their signature to a factor of three fainter than the lowest value predicted by inflationary models, Kogut said. In addition, the telescope will carry out its task 100 times faster than any ground-based observatory.

Good News, Either Way

Even if PIPER fails to detect the signature, the scientific community still would herald the mission a success. "It will be a big deal if they find the signal, but it also will be a big deal if PIPER can't see it," Moseley said. "It means that we need to come up with a different model of what happened in the early universe."

http://www.nasa.gov/scientificballoons

Last edited: Apr 26, 2016
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5. ### SchmelzerValued Senior Member

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Popular science about inflation is always horror.

Whatever the expansion rate in an FLRW solution $ds^2 = d\tau^2 +a^2(\tau) (dx^2+dy^2+dz^2)$, for a long enough distance there will be always some "expansion faster than the speed of light". With or without inflation, even with a deflation this would be the case.

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No more of a horror than still claiming an ether theory, and then pretending it does more than GR, but will not be recognised because of the collusion within mainstream cosmology to keep it from the mainstream acceptance .
Reminds me of the UFO's of Alien origin that the powers that be are hiding, or the conspiracy of 9/11 or even the faked Moon landings.

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8. ### SchmelzerValued Senior Member

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Oh, and who is making such claims? (I'm not. I had to look for translation of "collusion", thus, I'm sure I have never used this word.)

Then, can you explain me the meaning of "claiming a theory"?

Then, my remark was on-topic. I have criticized a particular claim of the OP. But your side remark against some ether theorist you have invented seems completely off-topic. Do you have to present something in defense of stupid claims about "the infant universe expanded far faster than the speed of light"?

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That's OK, something else you have learnt.
Ooops, sorry, I should have said an ether hypothesis.

As usual, you ignore the gist of the article...ie: evidence for Inflation.
And of course the universe could be said to be expanding FTL.
Take two objects far enough apart, and the recessional velocity, due to spacetime expansion will be in excess of "c"

10. ### SchmelzerValued Senior Member

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Of course. As a scientist, I criticize nonsense, independent of any gists or so.
It can be, but it is misleading. And it is even more misleading to say that it expanded FTL during inflation - which suggests that it is not expanding FTL if there is no inflation.

11. ### SchneibsterRegistered Member

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If their measurements are a factor of three better, then they should get a good enough signal to overcome the expected limitation that about half of the B-mode polarization that is not from dust is also not from gravity waves. This is a good experiment, and the article is right, if they find nothing then we will have a problem accounting for the observed size of the density fluctuations indicated by the CMB.

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As a scientists that wears his often self claimed independence like a badge of honour, and one who also pushes an ether as superior to GR, your criticism is understandable but entirely dismissed.
Most mainstream cosmologists see Inflation as part and parcel of the BB.

Rubbish. No indication at all that saying Inflation was FTL expansion, suggests that it is not expanding FTL other then Inflation. Just a cop out which you are adept at doing.

13. ### SchmelzerValued Senior Member

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This criticism has nothing to do with my ether theory, it is simply criticism of incompetent science journalism. Incompetent because the claim is nonsensical from the mainstream point of view.
Completely unrelated. I have not at all criticized that they have talked about inflation. The empirical evidence for inflation - in the technical sense, of $a''(\tau)>0$ - is good. The theories which define inflation are not that good, but this is another question.

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Cosmological Inflation is nonsensical from the mainstream point of view?
Wow!

WTF!

With all due respect Schmelzer, it's you and your own outlook on theoretical cosmology that's in serious question here: As well of course on your rather extreme bizarre political views. Perhaps there's a connection?

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So, tell me again Schmelzer, what are you claiming?

You ask a good question, one whose answer lies in the subtle difference between expansion that is faster than the speed of light and the propagation of information that is faster than the speed of light. The latter is forbidden by fundamental physical laws, but the former is allowed; that is, as long as you are not transmitting any information(like a light pulse), you can make something happen at a speed that is faster than that of light. The expansion of the Universe is a "growth" of the spacetime itself; this spacetime may move faster than the speed of light relative to some other location, as long as the two locations can't communicate with each other (or, in terms of light rays, these two parts of the Universe can't see each other). According to the theory of inflation, the Universe grew by a factor of 10 to the sixtieth power in less than 10 to the negative thirty seconds, so the "edges" of the Universe were expanding away from each other faster than the speed of light; however, as long as those edges can't see each other (which is what we always assume), there is no physical law that forbids it.

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And yes, I have seen the link to Sean Carroll's explanation which goes along with your own denial, but I prefer to accept that which gives the best explanation to promote understanding, certainly not some pedant remark/s from someone who is already known as a Maverick.
And while I respect and like Professor Carroll's outlook, particularly his view on the reality of time, in this case I prefer that of others like Professor Lawrence Krauss.
http://www.preposterousuniverse.com...never-expands-faster-than-the-speed-of-light/

Last edited: Apr 27, 2016
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17. ### SchmelzerValued Senior Member

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I tell you that it is stupid to compare the expansion of the universe with the speed of light. As well as with any other speed. Because what defines the expansion is a factor per time, not a speed (which is distance per time).
A quite common statement, but in fact it makes not much sense.
Another typical pop-science nonsense. Ok, in this case the number may be correct (I have not checked, therefore only maybe), and the unit is ok, so that this is already much better than comparing the expansion with the speed of light.

The funny thing is that if there would be no inflation, then, if we would consider the same amount of time with the same end, the expansion factor would be much greater. Or would be simply undefined because the BB singularity would be inside that time interval.

And I would recommend you not to talk about edges of the universe. Just a recommendation.

PS: The video is nice, but he makes an error at 2.23, where he claims that it is "due to the accelerated expansion" that we can, in some future, see the light of galaxies which move now away with more than the speed of light. In fact it is an accelerated expansion which can prevent us from seeing some far away galaxies forever. With a linear expansion, we will see every galaxy in the universe after a long enough time.

Last edited: Apr 28, 2016

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Ignoring the rest of your stuff that has already been answered and discussed, please tell me, where I have mentioned any edge of the Universe, or center for that matter, since I have often discussed the futility and stupidity of claiming either. Or is this another side track red herring of yours?

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Abstract:
The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne instrument to measure the polarization of the cosmic microwave background in search of the expected signature of primordial gravity waves excited during an inflationary epoch shortly after the Big Bang. PIPER consists of two co-aligned telescopes, one sensitive to the Q Stokes parameter and the other to U. Sky signals will be detected with 5120 transition edge sensor (TES) bolometers distributed in four rectangular close-packed arrays maintained at 100 mK. To maximize the sensitivity of the instrument, both telescopes are mounted within a single open bucket dewar and are maintained at 1.5 K throughout flight, with no ambient-temperature windows between the sky and the detectors. To mitigate the effects of systematic errors, the polarized sky signals will be modulated using a variable-delay polarization modulator. PIPER will observe at frequencies 200, 270, 350, and 600 GHz to separate the CMB from polarized dust emission within the Galaxy. A series of flights alternating between northern and southern hemisphere launch sites will produce nearly full-sky maps in Stokes I, Q, U, and V. I will discuss the current status and potential science returns from the PIPER project.
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http://science.gsfc.nasa.gov/665/research/

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No problem:

21. ### SchmelzerValued Senior Member

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Learn to read. I have criticized not inflation, but the journalistic description, which contained the misleading "expanding faster than speed of light" mem.

No. The only thing in question here is your ability to read and understand elementary texts.

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I never said that at all. Do you know the difference between a link and what I say myself?
Irrespective, what he meant in the article was that any two points are receding from each other FTL. A shame that again you ignore the gist of an article, preferring to concentrate on what could be said to be poor journalism.
More to the point perhaps is that you need to express what you are saying clearly enough just as I have in your "edges"claim.
I would expect you to say that as obviously untrue as it is.
You made those poorly made claims, and they were meaningless and non applicable as I have shown.

23. ### SchmelzerValued Senior Member

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Oh, I see. Sorry. So I have to modify my recommendation: Never link articles talking about edges of the universe. Just a recommendation.
No, it is not a shame, but a necessity. Articles about science have to be correct, and even minor errors and inaccuracies have to be criticized. An article with a nice "gist" full of errors is a bad article. BTW, not only in science, but in all other domains of journalism one is already happy if the gist of the article is not to lie, deceive, or stir up hatred.
(some cheap polemics disposed)