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by carsongross 4235 days ago
Another severe blow to the cosmological principle.
3 comments

No, because the quasars weren't aligned with each other globally (cosmologically), it appears they are aligned with whatever structure they are embedded in at large scales. I think the term is a filament, but I'm not sure.

If every quasar wherever we looked was aligned such that their axes of rotation were parallal, that would be a huge blow to the cosmological principal. Or more spookily, suppose all of the quasars studied were oriented with their poles lining up to some point in the universe. A good hint that some God created the universe for us, for example, would be for every single quasar's axis of rotation to be pointing at the earth.

But those things do not seem to be the case, and the cosmological principal appears to hold. Look at any corner of the universe, and quasars point in an arbitrary direction. Look at another corner, and they point in a different arbitrary direction. Zoom out, and now there is no cohesive direction. Homogeneity is preserved at scales much smaller than the largest structures we've observed, because the chains of quasars are themselves much smaller than the filaments and other super-structures that snake through the observable universe.

The principle is meant to apply only at a sufficiently large scale. If any particular scale goes against the principle, one can enlarge the scale to see if the principle still applies.
That still sounds like a blow to the meaningfulness or usefulness of the principle.
Why would it? If you enlarge the scale and find that the principle applies, it's useful.
And if all else fails, just scale out further... until you're effectively outside the universe.

Stipulate the presence of additional universes.

Then call the whole theoretical collection a "multiverse."

Voilà. We have no reason to believe this reflects reality, but it must be assumed...

...in order to preserve the Cosmological Principle.

genwin is talking about actual measurements, not speculation. Why are you throwing out a strawman?
You never get outside the universe, if it's infinitely large (and there's no evidence to the contrary).
Exactly
The alignments are exactly on the same scale of the filaments. It would be a contradition to the cosmological principle if, say, the alignments occurred only on one celestial hemisphere.
Is a line of basketballs all found to be spinning in the exact same direction more or less random than a line of basketballs spinning in random directions?

I know, I know. "Sufficiently large scale."

(lol)

Basketballs are not formed by gravity.

Edit: quote from the article:

“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[sic] what had been observed to date for normal galaxies,” adds Dominique Sluse of the Argelander-Institut für Astronomie in Bonn, Germany and University of Liège.

So clearly this was expected.