Magnetic bubbles at the edge of the solar system and CMB

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  • #1
zonde
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Main Question or Discussion Point

This article http://www.physorg.com/news/2011-06-big-edge-solar.html" [Broken] tells about discovery of magnetic bubbles at the edge of solar system.

As I understand they are around 100AU from Sun and around the size of 1AU. That makes them roughly 3.6° angular size.

Shouldn't these bubbles cause some effect in CMB?
If they do then the effect should be discernible as it would undergo rather detectable paralax.
 
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Answers and Replies

  • #2
Drakkith
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I don't believe the magnetic bubbles would have any effect on the CMB. Unless a magnetic field is extremely strong photons are generally not effected.
 
  • #3
zonde
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It's not about magnetic field affecting CMB. It's about magnetic field affecting cosmic rays.

From the article:
"The magnetic bubbles appear to be our first line of defense against cosmic rays," points out Opher. "We haven't figured out yet if this is a good thing or not." On one hand, the bubbles would seem to be a very porous shield, allowing many cosmic rays through the gaps. On the other hand, cosmic rays could get trapped inside the bubbles, which would make the froth a very good shield indeed.
If cosmic rays are stopped their kinetic energy have to go somewhere. So it must be radiated out as photons, right?
 
  • #4
Drakkith
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Hrmm. I don't know enough to say yes or no on that.
In the words of Futurama: "All I know is my gut says maybe."
 
  • #5
Chalnoth
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If cosmic rays are stopped their kinetic energy have to go somewhere. So it must be radiated out as photons, right?
Yes, but very slowly. They would only be able to capture relatively low-energy cosmic rays, and as the charged particles move around in the magnetic field, they would radiate via synchrotron radiation. The fact that we haven't detected these bubbles before now should show just how weak this radiation must be.
 
  • #6
Dotini
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Yes, but very slowly. They would only be able to capture relatively low-energy cosmic rays, and as the charged particles move around in the magnetic field, they would radiate via synchrotron radiation. The fact that we haven't detected these bubbles before now should show just how weak this radiation must be.
Is it possible that what we are calling CMB is actually radiation occurring in and around the bubbles?

Respectfully,
Steve
 
  • #7
Drakkith
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Is it possible that what we are calling CMB is actually radiation occurring in and around the bubbles?

Respectfully,
Steve
Unlikely. Otherwise we would see pretty severe differences between one point in the Earths orbit and another from parallax.
 
  • #8
Chalnoth
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Is it possible that what we are calling CMB is actually radiation occurring in and around the bubbles?

Respectfully,
Steve
Nope. The CMB is a thermal blackbody at 2.726K. The radiation from these bubbles would have an extremely different spectrum (not just a different temperature, but synchrotron emission isn't thermal at all). It also wouldn't be very smooth across the sky.

There's also the point that we can observe the imprint of clusters of galaxies on the CMB, so it is most definitely coming from beyond these clusters.
 
  • #9
zonde
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Is it possible that what we are calling CMB is actually radiation occurring in and around the bubbles?

Respectfully,
Steve
If you would think that big bang model is somewhat problematic then to develop alternative explanation for CMB multipole you would need some formations organized more or less symmetrically around solar system and with angular size somewhere around 1°.

But I would say there is not enough information about these bubbles to use it as explanation for anything else.
It might be more meaningful to take it another way around. What properties you would predict for those bubbles if you suppose they are the reason for CMB multipole.
 
  • #10
zonde
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Unlikely. Otherwise we would see pretty severe differences between one point in the Earths orbit and another from parallax.
As I understand CMBR satellites scan the sky in rather systematic way as they orbit around the sun. At least that's true for Planck satellite.
So it's not like you have full sky CMBR map for one satellite position and full sky CMBR map for another satellite position.

Another thing is that CMB multipole can not be seen directly. It's rather result of statistical analysis.

But yes it needs some analysis how parallax can affect data and explanation why it is not noticed. But to say something about it you would have to know very well the details about how the data is handled.
 
  • #11
Drakkith
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As I understand CMBR satellites scan the sky in rather systematic way as they orbit around the sun. At least that's true for Planck satellite.
So it's not like you have full sky CMBR map for one satellite position and full sky CMBR map for another satellite position.

Another thing is that CMB multipole can not be seen directly. It's rather result of statistical analysis.

But yes it needs some analysis how parallax can affect data and explanation why it is not noticed. But to say something about it you would have to know very well the details about how the data is handled.
Of course. I merely brought it up as I had just been reading about parallax and thought it applied to the CMB mapping as well. (IF the CMB was being warped by the bubbles that is)
 
  • #12
Chalnoth
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If you would think that big bang model is somewhat problematic then to develop alternative explanation for CMB multipole you would need some formations organized more or less symmetrically around solar system and with angular size somewhere around 1°.

But I would say there is not enough information about these bubbles to use it as explanation for anything else.
It might be more meaningful to take it another way around. What properties you would predict for those bubbles if you suppose they are the reason for CMB multipole.
As I understand CMBR satellites scan the sky in rather systematic way as they orbit around the sun. At least that's true for Planck satellite.
So it's not like you have full sky CMBR map for one satellite position and full sky CMBR map for another satellite position.

Another thing is that CMB multipole can not be seen directly. It's rather result of statistical analysis.

But yes it needs some analysis how parallax can affect data and explanation why it is not noticed. But to say something about it you would have to know very well the details about how the data is handled.
Pretty sure it's impossible to get around the three issues that I mentioned: that the CMB has a thermal black body spectrum, that the CMB is extremely uniform (to about one part in 100,000), and the imprint of galaxy clusters is visible on the CMB.
 
  • #13
zonde
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Pretty sure it's impossible to get around the three issues that I mentioned: that the CMB has a thermal black body spectrum,
To get thermal black body spectrum the only thing you need is black body i.e. body that only absorbs radiation but does not emit any (except thermal of course).

that the CMB is extremely uniform (to about one part in 100,000),
To get uniform thermal radiation you need uniform black body.

and the imprint of galaxy clusters is visible on the CMB.
For that properties of black body should not be so perfect after all so that emitted thermal radiation slightly depends on absorbed radiation (that is coming from galaxy clusters).

I would say it's rather speculative but definitely it is possible to get around the issues you mentioned.
 
  • #14
Chalnoth
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To get thermal black body spectrum the only thing you need is black body i.e. body that only absorbs radiation but does not emit any (except thermal of course).
Except the proposed emission here is synchrotron, which doesn't have a black body spectrum.
 
  • #15
Dotini
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If you would think that big bang model is somewhat problematic then to develop alternative explanation for CMB multipole you would need some formations organized more or less symmetrically around solar system and with angular size somewhere around 1°.

But I would say there is not enough information about these bubbles to use it as explanation for anything else.
It might be more meaningful to take it another way around. What properties you would predict for those bubbles if you suppose they are the reason for CMB multipole.
Yes, zonde, I as a skeptical layman do have (minor) problems with the big bang model. For me to accept that CMB is remnant radiation restricted to a thin shell at the very edge of the universe which suddenly decoupled from matter at some early point, I would thoroughly and rigorously have to rule out that it wasn't either (a) the ISM or (b) noise from earth (or its sun), which at least superficially seems more logical, and is just what the bubbles appear to be. If these magnetic bubbles are independently organized and sustaining structures, then they must have insulating (double) layers to keep them from merging. What do we know of these properties which may be pertinent?

The Planetary Society, which apparently funded the Voyager Mission when the government wanted to drop it halfway through, quoted Edward C. Stone, Voyager Project Scientist , saying, " If there's really reconnection going on, where the field is being annihilated, well, that can accelerate particles," he noted, "so there may be a source of energetic particles there." This implies to me that the bubbles may be an anomalous source of cosmic rays themselves.
http://www.planetary.org/news/2011/0612_Voyager_Discovers_Possible_Sea_of_Huge.html [Broken]

Lastly, let's not omit to mention and appreciate findings of the IBEX mission, also currently studying this region of space, which has made a startling series of discoveries which may have a bearing on our problem.
http://science.nasa.gov/science-news/science-at-nasa/2010/15jan_ibex2/
http://www.nasa.gov/mission_pages/ibex/news/solar-boundary.html

Edit: Note that IBEX makes clear that the heliosheath is currently rapidly contracting. This obviously opens the likelihood that it is also oscillating. Now if you as an astronomer wake up over coffee one morning with the news that your observation post is surrounded by a giant magnetic bubble wrapped in current sheets, wrapped yet again with a thick layer of smaller magnetic bubbles, and the whole thing is rapidly oscillating, you must immediately suspect you are dealing with something of considerable power and interest.

Respectfully submitted,
Steve
 
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  • #16
Chalnoth
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Yes, zonde, I as a skeptical layman do have (minor) problems with the big bang model. For me to accept that CMB is remnant radiation restricted to a thin shell at the very edge of the universe which suddenly decoupled from matter at some early point, I would thoroughly and rigorously have to rule out that it wasn't either (a) the ISM or (b) noise from earth (or its sun), which at least superficially seems more logical, and is just what the bubbles appear to be. If these magnetic bubbles are independently organized and sustaining structures, then they must have insulating (double) layers to keep them from merging. What do we know of these properties which may be pertinent?
The frequency spectrum of the CMB cannot be explained in another way. Here is the spectrum as measured by FIRAS:
[PLAIN]http://people.sissa.it/~dick/firas_plot.png [Broken]
Note that these are 50-sigma error bars, and still they're barely visible across most of the plot. Usually when plotting something like this I would thicken the lines to make things more readable, but in this case it would just make everything indistinguishable.

We have found no other way to produce such an incredible black body.

Then there is the Sunyaev-Zel'dovich effect. What happens here is that when the CMB interacts with the hot ionized gas in a cluster, it modifies the CMB spectrum in a very predictable way that is independent of how far away that cluster is from us (it tends to reduce the intensity just below the CMB peak and increase the intensity just above the CMB peak). Here is the paper describing the early set of SZ-detected clusters from Planck:
http://arxiv.org/PS_cache/arxiv/pdf/1101/1101.2024v1.pdf

This observation cannot be explained unless the CMB is coming from behind these clusters.
 
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  • #17
Dotini
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The frequency spectrum of the CMB cannot be explained in another way. Here is the spectrum as measured by FIRAS:
Note that these are 50-sigma error bars, and still they're barely visible across most of the plot. Usually when plotting something like this I would thicken the lines to make things more readable, but in this case it would just make everything indistinguishable.

We have found no other way to produce such an incredible black body.
Is this part of the data produced by the infamous COBE satellite? If so, that would be like resting your telescope on the Rock of Jello instead of the Rock of Gibralter. That project had many "issues". http://spacese.spacegrant.org/uploads/Requirements Config/COBE_case_study.pdf

I would not put all my eggs in this particular basket.

Very respectfully submitted,
Steve
 
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  • #18
Chalnoth
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Is this part of the data produced by the infamous COBE satellite? If so, that would be like resting your telescope on the Rock of Jello instead of the Rock of Gibralter. That project had many "issues". http://spacese.spacegrant.org/uploads/Requirements Config/COBE_case_study.pdf
Say what? There is nothing in that story whatsoever that calls COBE's results into question.

And besides, if it didn't work properly, there is basically zero possibility that the FIRAS instrument would provide such an accurate blackbody measurement.
 
  • #19
Dotini
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http://www.technologyreview.com/blog/arxiv/23556/
When cosmologists found that the variations in the background radiation were not distributed randomly but seemed to be imprinted with a pattern, more than a few of them scratched their heads in bewilderment.

Now H N Sharpe, an independent researcher in Bognor, Ontario, Canada, suggests that this pattern--called the quadropole moment--may not be a property of the background radiation at all. Instead, the cause may be much closer to home.

Sharpe says the culprit is the Solar System's termination shock where the outflowing supersonic wind from the Sun is slowed to subsonic speeds by interstellar winds.

The Voyager 1 and 2 spacecraft crossed this boundary in 2003 and 2007 respectively. Last year, scientists studying the data the spacecraft returned noticed that, far from being spherical as had been expected, the termination shock is asymmetric, distorted by some unknown forces.

The termination shock is a thin region of space in which there is a sharp change in the pressure, temperature, density, magnetic and electric field properties of space. That sound like anything familiar? It should.
In effect, the termination shock is a giant lens that ought to refract electromagnetic radiation passing through it. Any distortion of this lens could then be seen by observing isotropic radiation passing through it. Sharpe calls it a dirty lens.



http://arxiv.org/abs/0905.2978
A non-cosmological origin for the CMB quadrupole moment is suggested in this paper. Geometric distortions to an otherwise isotropic CMB could be imprinted on the CMB radiation as it propagates through the asymmetric termination shock formed at the boundary of the solar wind and the local interstellar medium. In addition to this boundary distortion, the Voyager spacecraft observed abrupt changes in plasma properties and rapidly fluctuating magnetic and electric fields as they recently crossed the termination shock and entered the heliosheath. Several mechanisms are discussed which could potentially imprint the termination shock distortion on the CMB. Temporal variations of this distortion due to solar wind pressure wind changes could manifest in the multipole moments of the CMB. http://arxiv.org/ftp/arxiv/papers/0905/0905.2978.pdf

http://en.wikipedia.org/wiki/Heliosphere

Respectfully submitted,
Steve
 
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  • #20
Chalnoth
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http://www.technologyreview.com/blog/arxiv/23556/
When cosmologists found that the variations in the background radiation were not distributed randomly but seemed to be imprinted with a pattern, more than a few of them scratched their heads in bewilderment.

Now H N Sharpe, an independent researcher in Bognor, Ontario, Canada, suggests that this pattern--called the quadropole moment--may not be a property of the background radiation at all. Instead, the cause may be much closer to home.

Sharpe says the culprit is the Solar System's termination shock where the outflowing supersonic wind from the Sun is slowed to subsonic speeds by interstellar winds.

The Voyager 1 and 2 spacecraft crossed this boundary in 2003 and 2007 respectively. Last year, scientists studying the data the spacecraft returned noticed that, far from being spherical as had been expected, the termination shock is asymmetric, distorted by some unknown forces.

The termination shock is a thin region of space in which there is a sharp change in the pressure, temperature, density, magnetic and electric field properties of space. That sound like anything familiar? It should.
In effect, the termination shock is a giant lens that ought to refract electromagnetic radiation passing through it. Any distortion of this lens could then be seen by observing isotropic radiation passing through it. Sharpe calls it a dirty lens.



http://arxiv.org/abs/0905.2978
A non-cosmological origin for the CMB quadrupole moment is suggested in this paper. Geometric distortions to an otherwise isotropic CMB could be imprinted on the CMB radiation as it propagates through the asymmetric termination shock formed at the boundary of the solar wind and the local interstellar medium. In addition to this boundary distortion, the Voyager spacecraft observed abrupt changes in plasma properties and rapidly fluctuating magnetic and electric fields as they recently crossed the termination shock and entered the heliosheath. Several mechanisms are discussed which could potentially imprint the termination shock distortion on the CMB. Temporal variations of this distortion due to solar wind pressure wind changes could manifest in the multipole moments of the CMB. http://arxiv.org/ftp/arxiv/papers/0905/0905.2978.pdf

http://en.wikipedia.org/wiki/Heliosphere

Respectfully submitted,
Steve
I'm not entirely sure why you posted this in this thread, as it has very little to do with your original post. This is an attempted explanation for a somewhat unusual feature of the CMB: that it has a low quadrupole moment. In reality, it isn't clear that the low quadrupole moment even needs explaining, as it is within the expected error bounds.
 
  • #21
zonde
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Low number multipoles in CMBR are quite strange thing.
This paper http://arxiv.org/abs/astro-ph/0603594v2" [Broken] argues that there is anti-alignment with dipole.

It seems interesting to assume some non-linear summation of some other different effect with dipole.
That other effect can be instrumental or from data processing.
But of course it would be interesting to analyze if it can be explained as local physical effect.

It seems that usually the problem is viewed as non-Gaussian variation in data but to me it seems that low number multipoles are strange by themselves not just their alignment.
 
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  • #22
Chalnoth
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Low number multipoles in CMBR are quite strange thing.
This paper http://arxiv.org/abs/astro-ph/0603594v2" [Broken] argues that there is anti-alignment with dipole.

It seems interesting to assume some non-linear summation of some other different effect with dipole.
That other effect can be instrumental or from data processing.
But of course it would be interesting to analyze if it can be explained as local physical effect.

It seems that usually the problem is viewed as non-Gaussian variation in data but to me it seems that low number multipoles are strange by themselves not just their alignment.
It would probably be beneficial to read the paper by the WMAP team on the subject:
http://arxiv.org/abs/1001.4758

Here is a popular article on the subject:
http://www.universetoday.com/55200/seven-year-wmap-results-no-theyre-not-anomalies/

Basically, when you do the statistics properly, there just isn't anything clearly out of the ordinary in the WMAP data.
 
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