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Old 13-November-2007, 06:26 PM
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tdvance tdvance is online now
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angular momentum could easily be an intrinsic property--so the universe could "rotate" without rotating within something (I know in General Relativity, there is something called "frame dragging" around a rotating body--perhaps the entire universe "frame" could be in rotation--i.e. space itself is rotating, or equivalently I think, spacetime is twisted like a DNA strand). I recall a proposal to measure universal rotation by looking at the distribution of spiral galaxies to see if they tend to align a certain way (either their north poles or south pols should show a preference for pointing toward a hypothetical center of rotation). This would likely fail--since we may only see a very tiny part of the existing universe, and if I remember right, for all we can tell, galactic allignments tend to be random (suggesting no, or nearly zero, universal rotation).

Of course, a galaxy has a magnetic field--and I'd imagine that means it has a magnetic north and south pole. This would likely differ from what we call the galactic north and sout h pole, defined according to its overall rotation. As someone mentioned, the north pole points in a direction parallel to the direction of the constellation Coma Berenices. (incidentally, that is why one of the Hubble Deep Field images was taken there--perpendicular to the plane of the Milky Way so fewer stars to get in the way of far away galaxies in that direction).
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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

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