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Detection of a Dipole in the Handedness of Spiral Galaxies with Redshifts z ~ 0.04

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bcrowell
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Jul25-11, 08:08 PM
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Longo, "Detection of a Dipole in the Handedness of Spiral Galaxies with Redshifts z ~ 0.04," 2011, http://arxiv.org/abs/1104.2815

If this is right, then I guess it would be the first possible hint of a nonzero rate of rotation for the universe. He doesn't attempt to state his results in terms of an angular velocity. I doubt that this type of anisotropy is consistent with inflation...?

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Dotini
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Jul26-11, 06:37 AM
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http://www.technologyreview.com/blog/arxiv/23410/

FWIW, Longo seems to think the spin axes might line up with the cold spot in the CMB.

"Michael Longo at the University of Michigan has long been searching for another asymmetry--a preference for right or left handedness in spiral galaxies. And he says he's found it, previously in an analysis of over 2600 nearby spiral galaxies and now in an analysis of 15,000 more.

The evidence seems to indicate that left handed spirals are more common in the northern hemisphere, above the northern galactic pole. And although the signal is less strong, right-handed spirals appear more frequently in the south.

What's more, Longo says the axis of this alignment points directly towards the mysterious cold spot in the cosmic microwave background, which was discovered in the southern hemisphere in 2004."


Respectfully submitted,
Steve
Dotini
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Jul27-11, 04:33 PM
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Ben, I'm astounded no one has yet commented on this thread.

If I'm reading Longo correctly, he seems to be saying that galaxies in our northern galactic sky rotate differently than those in our southern galactic sky. Which would put us in the middle. He says "parity asymmetry", but it seems overtly anti-Copernican to me. Please correct me if I'm wrong.

Thank you,
Steve

bcrowell
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Jul27-11, 04:39 PM
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Detection of a Dipole in the Handedness of Spiral Galaxies with Redshifts z ~ 0.04

Quote Quote by Dotini View Post
If I'm reading Longo correctly, he seems to be saying that galaxies in our northern sky rotate differently than those in our southern sky. Which would put us in the middle. He says "parity asymmetry", but it seems overtly anti-Copernican to me. Please correct me if I'm wrong.
I think it only violates isotropy, not homogeneity. If all galaxies rotate in the same direction, then an observer in the middle of them sees them as clockwise in half of the sky and counterclockwise in the other. It's like standing behind a clock whose face is made out of glass -- the hands appear to go counterclockwise from that perspective.

Of course the real question is whether it's right. Personally I'd consider it an extraordinary claim that requires extraordinary evidence.
turbo
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Jul27-11, 07:15 PM
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Could there be local measurements that don't accord to a more global model? Caution is advised, IMO.
Chronos
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Jul27-11, 11:18 PM
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I agree with bcrowell, extraordinary evidence is required to prove this is not just a selection effect or random anomaly. The claim rotation axes are aligned with the CMB 'cold spot' sets off my crank alarm. It looks like statistical snake oil to me.


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