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200,000 Elliptical Galaxies Point the Same Way
KentuckyFC sends us to arXiv, as is his wont, for a paper (abstract; PDF preprint) making the claim that 200,000 elliptical galaxies are aligned in the same direction; the signal for this alignment stands out at 13 standard deviations. This axis is the same as the controversial alignment found in the cosmic microwave background by the WMAP spacecraft.
Do they give any reason that this might be so? Are the galaxies in the same area? Did they all form from some insanely massive rotating structure or something?
# cat
Damn, my RAM is full of llamas.
Huh. I don't really have a great deal of specialist knowledge on cosmology, but this seems to put a lower bound on the distance over which we can assume the universe is isotropic (i.e. the same in all directions). The abstracts puts an upper bound on the redshift of the galaxies involved in the survey, which is presumably roughly equivalent to limiting the distance they are from us, but surely the fact that this net angular momentum axis is closely aligned with an axis identified in WMAP data indicates that this is a far larger scale phenomenon?
They do. There's a monkey there with a bone as well.
Evil people are out to get you.
It's not wasting time, I'm educating myself.
http://www.youtube.com/watch?v=Da2byMoEG30
Politics is Treachery, Religion is Brainwashing
It's been posted before, but if this sort of thing interests you, get over to Galaxy Zoo and help them classify galaxies.
It seems you do need 200,000 elliptical galaxies to know which way the wind blows.
So this might help explain in Star Trek how all ships are always keeping the same orientation / sense of "up"...
SO YOU'RE GOING TO DIE: The Comic for Dealing with Death
all your axis are belong to us.
never bring a twinkie to a food fight.
I read the article, and there seem to be a few problems he doesn't really address. First, he assumes that all elliptical galaxies have a point-of-view from which they appear circular. I don't think anyone has determined this to be the case, and he doesn't really have a way to get this from his data. Secondly, he doesn't give much real discussion to the error in the measurements, which is significant. No preffered axis of alignment would fall well within his measurement uncertainties. Finally, the 13-standard deviations is not from any real sort of error propagation, but from some random computer generated results. Could be interesting, but to be taken with a grain of salt.
nope - the turtle.
"See the TURTLE of enormous girth,
On his shell he holds the earth.
If you want to run and play,
Come along the BEAM today."
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
god doesn't play dice
he plays with magnets
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Einstein did not say that there cannot be a center of the universe.
What he did say is that for the purposes of measurement, there exists no privleged metric. All this says (All?!) is that there is no overall coordinate system that will be superior to all other coordinate systems.
If things started out as a big bang, on some scale, we will find a "center" of the universe. Is this an astronomy-shaking discovery? No. Maybe a tremor or two, for diehard relativeists. We already know that for specific purposes, there is often a preferred metric for computational or navigational purposes. Remember back in the Apollo program when the physics guys tried to explain that at a specific point, the coordinate system for the spacecraft shifted over from Terra-centric to Luna-centric, and the reporters looked at the "jog" in the plot and asked if the spacecraft would feel a "lurch" as it passed this point?
It's not nearly as big a deal as, say, whether Pluto is a "planet" or not. Pick a label, pin the sticker on the rock, except in this case, the rocks are superclusters of galaxies.
Don't take life too seriously; it isn't permanent.
Now if these 200,000 galaxies are all in a particular region of the universe, THAT would be explosive news, but, unless I completely misread the article, this isn't the case.
It is the case. They were specially selected to be close to us (redshift < 0.20). I suspect these 200,000 galaxies are a fairly significant fraction of all the galaxies near us.
Of course, they are close to us because more distant galaxies would be too difficult to investigate, but this doesn't change the fact that they are all in the same particular region of the universe.
My reading of the abstract is that he looked at a sample size of 200,000, and found a 13-SD bias to one direction in that sample size.
can someone give me the 'play by play' brief on the significance of the orientation of the galaxies and why the chance is so slim that they align as they do?
I'm not a Cosmologist, but one would expect galaxy orientation to be pretty much random. As an example, think about if you threw a bunch of nails in the air. At any given time you'd expect the nails orientation to be pretty random (ignoring air effects, and any bias given by your throw). If they all aligned in a certain way though, you'd be surprised and start looking for a cause. (In this case say a strong magnetic field in the room).
If this is true, there must be something orienting the alignment of galaxies. That could be either some bias in the big-bang, some outside force we don't understand, or something else.
AccountKiller
We're all being sucked into the same black hole!
APK quotes people (including myself) without context and should not be trusted. Just thought you should know.
Let's note that:
1) This guy is a high-energy physicist, not an astronomer.
2) He has two published articles on extragalactic astronomy, both from the early 90s, which have picked up a grand total of 4 citations.
3) He has put up 3 papers on the arXiv in the last few months, all on this subject. None of them are stated to have been submitted for review, and indeed they are not in the style of any of the major relevant journals.
Yeah, yeah, ad hominem and all that. I'll read it more carefully later if I have time (but I'm a bit busy writing a paper of my own, like, for submission and peer review and all that). He does appear to enjoy abusing statistics, both here and in his earlier papers.
I just kinda think that Slashdot could report on all the many scientific discoveries that are actually likely to be true, rather than grand claims based on a couple of preprints by someone with little experience in the field.
I have little direct experience with this, but I suspect that optical distortions could be the cause of the effect he is seeing. The universe may very well have some weird features, but this paper is not a careful analysis.
...well, I have a MS in Physics, anyway. Well, Applied Physics. In semiconductors. Anyway...
I think another poster said it a bit more intuitively, that the point is now smeared out everywhere. That sounds roughly right to me.
Another thing to realize is that the Big Bang doesn't mean that an explosion happened in a single point in empty space, and then everything expanded outward. It's that space itself was compressed down into a single point, and then expanded. There was nothing outside the Big Bang for it to expand out into. Every point in the universe was infinitely closer together. All the energy was really close together--really dense--so it was really hot. Then as things got less dense, the temperature decreased. In one sense, everywhere is the center of the Big Bang.
This is also why distant galaxies can be receding away from us faster than the speed of light. Because expansion doesn't mean that galaxies are moving through space. (In relativity, nothing can move through space faster than c.) Instead, the distance between us is increasing as space itself expands. (You can visualize that as making two marks with a pen on a deflated balloon, and then blowing up the balloon. The two marks don't move on the balloon, but they do get further apart.)
IANAAP either, but I see it like this: imagine you have 4 spinning tops in the corners of a square. (The spinning tops are the galaxies.) The square itself doesn't spin, but the round things in the corners do. If all 4 rotate in the same direction, the system has a decidedly non-zero angular momentum, namely the sum of the 4. You can also easily find a frame of reference (e.g., centered the centre of the square and with the X and Y axes aligned with the side of the square) that doesn't rotate, and measure everything relative to it.
Or if it makes it easier to imagine, think of the science gag of having a very fast spinning flywheel in a suitcase. Ask someone to carry it for you, or leave it around and see if anyone tries to steal it. (Though these days it'll more likely be the blown up by the SWAT or whatever equivalent your country has.) If the suitcase is horizontal (lying on the side), someone's going to have a beast of a time trying to pick it up. Or if it's standing, they'll have a beast of a time taking a corner with it. Though the suitcase (universe) doesn't rotate, the flywheel (galaxy) in it does, and the angular momentum of it all is very much non-zero.
Now think of a suitcase with 4 flywheels in it, or 200,000 little flywheels. The suitcase itself doesn't rotate, the centres of the wheels don't rotate around anything, but the total system has a total angular momentum. Anyone trying to mess with that piece of luggage is in for a bit of surprise.
A polar bear is a cartesian bear after a coordinate transform.
"A discussion of possible causes for these alignments is beyond the scope of this paper. "
The sentence abouve is followed by: "R. Buniy et al. (2006) discuss a universe that is not spherically symmetric due to magnetic fields or cosmic defects in the context of the CMB alignments. A large scale cosmic magnetic field acting on protogalaxies in the early stages of galaxy formation seems to provide a possible mechanism for explaining the elliptic and spiral spin alignments and has been proposed as a mechanism for causing the CMB alignments by Campanelli et al. 2006." i.e. We don't know.... i.e. but here a couple of ideas.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
Everyone is asking "why?" as in "Why are they aligned." My first thought was, "What the hell are they all pointing at?" Is it God? Is it the Restaurant at the End of the Universe? Is it Mecca? Maybe it is just a REALLY big magnet. The answer to the 'what' question might go a long way toward answering the 'why' question.
Anyway since I don't think that galaxies are likely to change their orientation, and remain tidy spiral galaxies, this suggests that there was a common influence on the creation of all of these galaxies!
-- QED
The fingers of god effect is simple - the doppler shift of a galaxy is proportional to the distance, according to Hubble's observations. If you do a plot of galactic positions, using the observed position in the sky and the red shift as the third dimension, you see what appear to be long, skinny clusters, all pointed directly at you. This happens because in tight clusters, galaxies are attracted to each other gravitational and have a range of velocities which is relatively large. So there's an added velocity on top of that caused by the expansion of the universe, which changes the distance you'd compute by Hubble's law.
It's not wasting time, I'm educating myself.