I'm skeptical of the claim that this minimum spanning-tree is any less random than the rest of the quasars depicted in the Picture linked below. (Given that gravity attracts, at least on relatively small cosmological scales.) How could one decide, with reasonable confidence? --Dan On 2013-01-11, at 9:51 PM, Warren Smith wrote:
A 73-quasar object called the "large quasar group" has been found that is 4 billion light years long. It was found with a 3D min-spanning-tree algorithm on a dataset of 105783 quasars. This is allegedly the largest thing ever seen.
Quasars tend to clump together in organized-looking structures, not "randomly distributed." This seems a good deal larger than "galaxy superclusters." Is this object for real, or merely what would have been expected to happen by examining enough random points? They argue the former, but I find their argument unclear and hence unconvincing. They think this object has 40% greater "local density" than it would have had with uniform universe.
Roger G. Clowes, Kathryn A. Harris, Srinivasan Raghunathan, Luis E. Campusano, Ilona K. S"ochting And Matthew J. Graham: A structure in the early Universe at z~1.3 that exceeds the homogeneity scale of the R-W concordance cosmology, Monthly Notices of the Royal Astronomical Society (11 January 2013) http://mnras.oxfordjournals.org/content/early/2013/01/07/mnras.sts497
Picture: http://mnras.oxfordjournals.org/content/early/2013/01/07/mnras.sts497/F1.lar...
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