200,000 Elliptical Galaxies Point the Same Way 448
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.
Why? (Score:5, Interesting)
Assumption busting... (Score:4, Interesting)
which beam (Score:2, Interesting)
Re:Why? (Score:5, Interesting)
It might mean that the angular momentum of the universe is nonzero, if a majority of them are turning the same direction. Or, even if they all cancel out, that momentum in the early universe tended to be oriented in a plane. (IANAP, just a guess but seems logical)
I'm curious if the Milky Way is a part of the alignment.
Re:Assumption busting... (Score:5, Interesting)
I have to wonder - Could this particular anisotropy account for the Voyager paradox? That would set a much lower bound...
Even if not, though, I really find this sort of anomaly fascinating. Almost everything cosmology has found since the dawn of modern science has pointed to a bleak, cold, basically empty univers that goes on identically forever in every direction. Even learning that the universe has some underlying structure would somehow seem a lot more comforting.
A grain of salt (Score:4, Interesting)
Why Not? (Score:5, Interesting)
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.
Re:Why? (Score:5, Interesting)
Re:Why? (Score:3, Interesting)
Layne
Re:Translation? (Score:5, Interesting)
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.
Re:Why? (Score:2, Interesting)
IAAP, but don't want to be understood as criticizing the author.
Re:Why? (Score:5, Interesting)
Although... thinking as I type here... say you were sitting on a massive spinning top, and all you could see was the spinning top. You'd still feel centrifugal force, as a result of its spinning. Could be an interesting explanation for dark energy?
(and yes, now I remember that important word "inertial" from A-level Physics lessons. Meh...)
Little discussion of instrumental systematics (Score:3, Interesting)
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.
Re:Assumption busting... (Score:2, Interesting)
There's not only the Voyager anomaly (which we have very poor data of and may have totally conservative causes).
Much more interesting is the Flyby anomaly [wikipedia.org], an unexpected and unexplained energy (velocity) increase during Earth flybys of satellites (or probes). It has been observed with at least four satellites yet and seems to show that our understanding of gravity/mass is subtly wrong in a very fundamental way.
Re:Why? (Score:3, Interesting)
Elliptic Galaxy Axis 183±8 deg 41±8 deg
North Galactic Pole 192.9 deg 27.1 deg
1st no. is right ascension (longitude for stars), second is declination (latitude).
This is really an amazing result. The galaxies way over there on the "left" side of the Universe know what the galaxies on the "right" are doing! It's so amazing, it makes you wonder if it might be wrong. For example, it might really be a property of some more local grouping of galaxies. Don't take it at face value -- yet.
Re:Centre of the universe (Score:4, Interesting)
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.
Re:Before we get too excited (Score:2, Interesting)
Re:Why? (Score:4, Interesting)
You're right. That sucks.
Basically the idea behind BD, and the other ST and STV theories, is that there is an additional field, not just the tensor field of GR. One of the side-effects of the field in the BD theory is that angular momentum "falls out" of the universe. This is actually kinda important.
In traditional models, the conservation laws you know don't really _have_ to exist. For instance, if the universe was shaped like an egg, billiard balls would always roll into one corner of the table because there's more mass on that side of the universe. The fact that it is conserved says a lot about the universe, specifically that is symmetric around any point in 3-space. Conservation of angular momentum is similar; it says the universe is symmetric around other axis as well -- linear momentum would still be conserved in a universe shaped like a cigar, along any axis the gravity is still even, but in this case a spinning object would speed up and slow down. Conservation of energy is due to the fact that the universe is symmetrical in time, physics in the past is the same as it is today.
Ok, but like I said, those laws don't _have_ to be true, and this bugged the hell out of a lot of people over the years. I forget which one of them, I think Brans, was thinking about what would happen if you spun a dish full of water in an empty universe... would the water rise up the sides? And if it doesn't, why not? Isn't either answer a little weird?
The extra field in DB theory answers the question -- the answer is "yes", the water will rise up on the sides. It wasn't designed to do that, at least I don't think so, but it ends up popping out of the math.
So basically if you end up with odd angular momentum terms in the universe, it MAY suggest that some other model of gravity might be more correct. Right now everything we've ever measured can't tell between the various models, but this might.
Maury
It's the first lure of the rosetta (Score:3, Interesting)
Heh (Score:3, Interesting)
Re:Before we get too excited (Score:1, Interesting)
I deleted from my inbox today an email from someone who has disproven the Uncertainty Principle. Of course, I didn't discard it simply because it was sent to me unsolicited by someone in China with a non-academic address, because that would be unscientific. He could be right, and have overturned quantum mechanics, because science is a claim assessment tool, not a citation index. So I looked at the first paragraph, saw that he mistated both the definition and the meaning of the Uncertainty Principle, while making some dubious assertions about the nature of quantum mechanics, thus indicating that he doesn't actually understand the very thing he claims to disprove. Thus having examined the work on its own merits, I deleted the email, rather than running to submit it to Slashdot.
I don't think at all that Dr. Longo is a crackpot. But his background raises flags, particularly when one has seen many of these advanced-career physicists who move over into astronomy and quickly make grand discoveries. Points (1) and (2) do not make me disbelieve his results. They do make me look at the actual work, which makes me disbelieve his results.
Again, all three points I made are relevant to whether this kind of thing should be announced in places like this. All three should make someone look into the actual science, or ask someone who can, before plastering it on a highly-read website, where it will be taken as fact by those who don't (through no fault of their own) know better. That was my concern, not whether he should be ignored by the scientific community. And I know, I've now spent far, far longer on this than I would have by just ignoring these posts myself. But while I don't come to Slashdot to learn astronomy, I'd prefer that the people who do learn things here get real science and not the fringe.
I am "capable" of doing what my high energy colleagues do, in the sense that I can write the programs they can and fit the models they do. I am not "qualified", however, to take a stack of semi-reduced data from one of them and get a believable answer, because I don't know the systematics and subtleties. I've no doubt that Dr. Longo is perfectly capable of understanding astrophysics at the level required to interpret results from the data, but he demonstratably does not understand the reduction of Sloan data, as pointed out by various commenters here. His results are therefore highly suspect. The fact that he doesn't want to get it reviewed only makes things worse.
Re:Why? (Score:3, Interesting)