Researchers detect B-mode polarization in cosmic microwave background

Researchers working at the South Pole Telescope (SPT) have detected tiny fluctuations—known as B-mode polarization—in cosmic background radiation. The team describes their findings in their paper they've uploaded to the preprint server arXiv.

Scientists believe that approximately half a million years after the Big Bang, the universe began switching from a state of plasma and energy to one where temperatures had dropped to a point where the universe became transparent enough for light to pass through. That light is known as cosmic microwave background (CMB) and is still visible today. Cosmologists studying it have formed the basis of a theory known as inflation—where the universe came to exist as it does today through a process of very rapid expansion just after the Big Bang.

In order to prove that the is correct, scientists have been studying minute fluctuations in the temperature of the CMB—they revel fluctuations in density of the . They also study fluctuations of the of the CMB which is due, it is believed, to radiation being scattered across the universe by the energy of the Big Bang. Fluctuations in polarization were for a time merely theory, but in 2002, they were actually detected, giving credence to inflation theory. Those fluctuations were given the name E-mode polarizations. Theory has also suggested that there are also B-mode fluctuations in polarization, which are far more subtle—they are thought to describe the rotation of CMB polarization. Finding evidence of them has been extremely difficult, however, as they exist as just one part in ten million in the CMB temperature distribution. But now it appears the team at SPT has done just that, adding further credence to the inflation theory. The researchers report that they were able to detect E-mode polarization due mostly to improvements in detector technology.

Adding credence isn't the same as finding proof of a theory, of course, and that's why scientists believe the detection of E-mode polarizations is so important. Many believe it will ultimately lead to the detection of primordial gravitational waves—immense ripples in space-time that theory suggests should have come about as a result of the force of inflation. If they can be detected, the theory of inflation would likely become the accepted theory regarding the early formation of the .

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More information: Nature doi:10.1038/nature.2013.13441
Journal information: Nature , arXiv

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Citation: Researchers detect B-mode polarization in cosmic microwave background (2013, July 26) retrieved 20 August 2019 from
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Jul 26, 2013
Yeah, well, make up your minds guys. The other article a few entries down is explaining how even the proponents of this theory are shooting holes in it due to matter and energy not being evenly distributed as it should be.

When are you crackpots going to admit you're crackpots?

Jul 26, 2013
" temperature of the CMB—they revel fluctuations in "

You misspelled "reveal" in that.

Jul 26, 2013
This writer also seems to have gotten "B" and "E" mode polarization switched from the first part to the end of this article.

Jul 26, 2013
The Nature article is has a very clear explanation of the subject of this article.

Jul 26, 2013
Meaning that detecting B-modes are good, but these small spatial scale lensing B-modes are not the large scale B-modes indicative of primordial gravity waves,

@Lurker: The inflationary standard cosmology is named that precisely because it is the accepted mainstream theory. The crackpottery is on the other side, I'm sure. The homogeneity observed is quite enough to accept it, so no "holes" from data in that regard.

However SC is not unambiguously constrained, and finding primordial gravity waves would go a long way towards rejecting alternatives.

Jul 26, 2013
@Lurker: Assuming it is this article: , it says exactly what I surmised. It is the vaunted large scale deviations, which is within what the theory predicts. It is a research strategy if you think they will tell you something or not on the main theory.

But it is a win for the main theory, because as Lasenby says, it rejects non-main alternates: ""[This] data is really putting pressure on some ***alternative*** inflation models...". [My ***]

Jul 27, 2013
Re: "They also study fluctuations of the polarization of the CMB which is due, it is believed, to radiation being scattered across the universe by the energy of the Big Bang."

It's interesting that people see no problem with using science to study a non-falsifiable creation event, whereas all hell breaks loose when others try to apply science to understanding mythological archetypes and petroglyphs.

Jul 28, 2013
The homogeneity observed is quite enough to accept it, so no "holes" from data in that regard

Well, there was an article recently ( and citing new data and research of the very big scales and there are still bigger structures found that were not expected while using the cosmological principle's assumption of homogeneity on the very big scales.

There are structures on every scale of the Universe, because the Universe can be described as a fractal. The data does support this notion and it does refute the assumption of homogeneity of cosmological principle.

Jul 28, 2013
Re: "There are structures on every scale of the Universe, because the Universe can be described as a fractal."

Indeed, and a good question which should have a physical (rather than metaphysical) answer is WHY. After all, some sort of ongoing physical process is creating the self-repetition over many orders of magnitude. It seems dubious that either a creation event or gravity is responsible for these similarities. Most people are already familiar with the similarity between the neuronal networks and the large-scale cosmic structure, but far fewer have been exposed to the interstellar skeletal and pinwheel structures which can be observed.

There have been a number of papers over the years by AB Kukushkin and VA Rantsev-Kartinov which claim to show morphological similarities between cosmic and Tokamak plasmas. The researchers have apparently deployed sophisticated machine learning algorithms to identify these structures. I count 26 papers that I've been able to identify so far ...

Jul 28, 2013
Note that, best I can tell, Kukushkin and Rantsev-Kartinov are independent researchers -- who like Anthony Peratt and Gerrit Verschuur -- do not call themselves "Electric Universe" theorists or even proponents.

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