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Tzarkoth
2014-Nov-22, 03:35 PM
Hi Guys,

Just a quick question about Quasers.

According to the following article, " The new VLT results indicate that the rotation axes of the quasars tend to be parallel to the large-scale structures in which they find themselves. "

http://www.dailymail.co.uk/sciencetech/article-2842418/Mystery-spooky-pattern-universe-Scientists-supermassive-black-holes-aligned.html

Reading into the article, the sample size is 93 Quasers, I thought we knew of about 12000 ... 93 of 12000 doesn't seem like a large enough sample to draw any firm conclusions.

The team was led by Damien Hutsemékers, however I can't find any associated paper mentioned in the article, or anything over at arXiv.

How is the Great Sloan Wall aligned to us, if this article bears any truth shouldn't all those galaxies be aligned in a similar fashion ?

Cougar
2014-Nov-22, 06:12 PM
Just a quick question about Quasers.

First of all, it's quasars. :p


According to the following article, " The new VLT results indicate that the rotation axes of the quasars tend to be parallel to the large-scale structures in which they find themselves. "

Interesting. But that link and article seemed rather tabloid-esque. This one's a little better:



Spooky alignment of quasars across billions of light-years
Date: November 19, 2014
Source: European Southern Observatory - ESO (http://www.sciencedaily.com/releases/2014/11/141119084506.htm)



The article notes:



"A correlation between the orientation of quasars and the structure they belong to is an important prediction of numerical models of evolution of our Universe. Our data provide the first observational confirmation of this effect, on scales much larger that what had been observed to date for normal galaxies," adds Dominique Sluse of the Argelander-Institut für Astronomie in Bonn, Germany and University of Ličge.




Reading into the article, the sample size is 93 Quasers, I thought we knew of about 12000 ... 93 of 12000 doesn't seem like a large enough sample to draw any firm conclusions.

We may know of a lot, but we don't know their spin axes. This team had to measure those, and it can only be measured indirectly:



The direction of this polarisation, combined with other information, could be used to deduce the angle of the accretion disc and hence the direction of the spin axis of the quasar.



93 is a pretty good sample size....

Cougar
2014-Nov-22, 06:56 PM
Apparently quasar polarization alignments have been known since at least 1998, as mentioned in this 2005 paper (pdf). (http://arxiv.org/pdf/astro-ph/0501043.pdf) Larger sample sizes are also mentioned. I imagine finding the largest-scale distance between such alignments has been a contest over the last several years. It kind of makes sense, though, that the gravitational effect of a long massive filament could initially affect the spin axes of the galaxies forming within it.

Tzarkoth
2014-Nov-23, 02:30 AM
First of all, it's quasars. :p

This is what I get for posting late at night. :-)

Seems that 93 is a good number after all, given the extra work involved, and the selection criteria that might be applied, as suggestive of the paper you have linked.

Something to read and understand, thankyou.