Article on New Planck Satellite data

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Any early ideas on what the lopsidedness means?
Funny, I stumbled upon that term a couple of hours ago here: The Lopsided Universe (Sean Carroll). I had not heard about it before.
 

Chronos

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The concept is faulty.
 
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My first thought was that we are observing it from edge-on, and not from the top or bottom.
 
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The concept is faulty.
Do you mean the interpretations of what is seen are faulty? Because the effect is pretty clear.

I believe most of the interpretations included the "pre BB" commented by Carroll are no more that "shots in the dark" at this point.

They just can't fit what is observed(an apparently preferred direction on the CMB- what they call lopsidedness), whith the current cosmology model. Anisotropy at those vast scales is simply not allowed in our models.

So we have a problem, and so far noone is apparently paying much attention to it except for some wild speculations (mentioned in Carroll's blog) that obviously aren't allowed here.
 
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My feelings on this is not being caused by any multiverse theories.
My initial feelings on this is that what were seeing is some property of thermodynamics or energy density distributions at play.
 
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The concept is faulty.
Slate article interesting....
concept maybe, but so far two separate satellites record it...anyway time will tell....
 
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I just want to point out that I mentioned Carroll's blog (which is about a paper from 2008) because it described the term "lopsided", which I had not heard before. According to Wiktionary "lopsided" means "Not even or balanced; not the same on one side as on the other." My intention was not to try to interpret or speculate about the effect. :wink:
 
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More about "lopsided universe" from a Planck team spokesman in Alan boyle NBC press release:

Efstathiou said the Planck data also pointed to some "strange features" in the cosmic microwave background that may point to new frontiers in physics, including an unexplained dip at one point of the power spectrum, and an unusual distribution of large-scale fluctuations that roughly followed the plane of the solar system.

"Why characteristics of the CMB should relate to our solar system is not understood. ... I was explicitly told not to say anything about God in this talk — which I've just violated," Efstathiou said half-jokingly.
 

Chalnoth

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If we see something in the overall universe that correlates strongly with our own solar system, then chances are what we are seeing is light from our own solar system contaminating the result.
 
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If we see something in the overall universe that correlates strongly with our own solar system, then chances are what we are seeing is light from our own solar system contaminating the result.
That is much more reasonable than attributing the anomalies to cosmic variance, as you seemed to be doing in the other thread; cosmic variance is by definition random, it cannot systematically be related to the ecliptic like all WMAPs and now Planck with different scanning strategy, for all of the anomalies in the different angular moments, whether it was the AoE anomaly, the cuadrupole/octopole alignment, the amplitude of temperatures between sides of the ecliptic (lopsidedness).... relate to.
The problem is contamination from the solar system has been claimed to have been exhaustively eliminated from the maps.
There are also the late time ISW effects from clusters that have been tried for some of the WMAP anomalies(substracting them reduces some of the anomalies in WMAP), but I'm skeptic they will do the same for all of the anomalies from the Planck data.
 

Chalnoth

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That is much more reasonable than attributing the anomalies to cosmic variance, as you seemed to be doing in the other thread; cosmic variance is by definition random, it cannot systematically be related to the ecliptic like all WMAPs and now Planck with different scanning strategy,
I was talking about the lopsided universe, rather than the quadrupole itself. The quadrupole measurement is similar but different, and it is telling that that measurement is nearly identical between the two instruments (this would not be expected to be the case if it was due to either the solar system or some instrumental systematic).

The quadrupole is most likely just down to cosmic variance. And yes, apparent patterns do emerge with shocking regularity in completely random signals.
 

marcusl

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How are these observatories able to measure the CBE without big spurious signals from stars and galaxies. Don't they emit microwaves?
 

Drakkith

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How are these observatories able to measure the CBE without big spurious signals from stars and galaxies. Don't they emit microwaves?
I believe they are able to be removed through various processing techniques. I've done this before with a picture of the Andromeda galaxy, where I removed the light from the core, letting me see the dust lanes all the way through without having to mess with the brightness and contrast settings.
 
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And yes, apparent patterns do emerge with shocking regularity in completely random signals.
How do random large scale early universe fluctuations manage to manifest themselves as the same kind of anomaly in a period of several years of detection?
 
I'm going to say something. This is speculation but I wouldn't characterize it as "wild" given recent discoveries. You guys will probably disagree. Being a guy interested in science, I keep up with the news. Evidently the Higgs mass combined with the top quark indicate that the vacuum is (possibly) meta-stable. If this is true then it's possible that the spacetime we experience bubbled out of a previous less stable vacuum.

I wouldn't necessarily say our perspective has anything to do with the change in CMB (in regard to the previous conversations). Obviously we may be getting artifacts from the solar system but star systems and galaxies are in every possible direction so it's certainly possible by sheer coincidence that a lot of star systems and/or galaxies (ours included) would be orientated this way.

Now, my question to the scientists here:
Is the change in average temperature of the CMB a smooth transition from one side to the other or does it abruptly change?

If it's a smooth transition then doesn't that imply a location where the big bang began? Or in this case, possibly the location that the meta-stable vacuum bubbled out of the less stable vacuum? If the change in temperature is abrupt, then I don't think any such implications would arise but maybe something else will result?

I don't think a vacuum bubbling out of a previous vacuum really changes big bang theory all that much other than it has a start point and is likely still expanding and converting space somewhere wayyy beyond the visible universe. Obviously the closer to the start location the cooler. Aside from that it would still bubble just like the big bang except instead of occurring in all of space at once, it's only happening at the edges and moving outward very quickly.

I want to apologize for my wild speculation. I'm just putting this together with the recent Higgs news because it's on my mind.
 

Drakkith

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Now, my question to the scientists here:
Is the change in average temperature of the CMB a smooth transition from one side to the other or does it abruptly change?
It's very smooth as far as I know. The small scale fluctuations can be abrupt, but the overall difference is minor and on a larger scale.

If it's a smooth transition then doesn't that imply a location where the big bang began?
No.
 
What kind of new physics can produce these CMB anomalies observed at large angular scales? I think it might be related to quantum gravity as they may hint at physics at the time of big bang that's amplified by inflation
 

Chalnoth

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How are these observatories able to measure the CBE without big spurious signals from stars and galaxies. Don't they emit microwaves?
For the most part, they're just too dim. In the frequencies where the CMB is brightest, we can only barely see the dust in our own galaxy (except when looking directly at the center). Andromeda is also hard to see in these frequencies, and that is the galaxy closest to us.

There are, however, radio quasars that are somewhat bright across all frequencies, and the brightest of these are simply masked out.

That said, the small contributions from billions of galaxies out there do add up, and do contaminate the power spectrum at small scales. These aren't subtracted in the maps, but their level of contamination is estimated from the data (basically, the statistics of these contaminants, and thus the shape they add to the power spectrum, is very different from that of the CMB).

Anyway, you can see more detail here:
http://arxiv.org/abs/1303.5075

You can see the masks they used on page 5, where the black regions are the places where they don't use data. You can see that they don't use the data from our own galaxy, or for a series of point sources away from the galaxy.

The clearest plot of the effect of the foregrounds is found on page 12, where you can see that at very small angular scales (high [itex]\ell[/itex] = small scales), the signals at the different frequencies start to go above the CMB line. Note that different frequencies are impacted by different amounts. This extra boosting of the signal at small scales is then subtracted for the final power spectrum estimate.
 

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