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View Full Version : Cosmology without dark matter or dark energy



trinitree88
2009-Sep-15, 06:58 PM
The authors, Barak and Leibowitz argue for a cosmology entirely without Dark Matter or Dark Energy. snowball or avalanche? Fun. pete


see:http://arxiv.org/ftp/arxiv/papers/0909/0909.2581.pdf

Kwalish Kid
2009-Sep-16, 02:43 AM
Snowball in hell. I haven't read through the entire thing yet, but it seems suspect. One thing that the authors are wrong about is the nature of the evidence for dark matter and dark energy. They need to address the evidence from WMAP if they want to dethrone dark energy.

Cougar
2009-Sep-16, 03:27 AM
Here's their explanation to replace dark matter:



...according to General Relativity (GR), gravitation is the contraction (curving) of space around masses. Hence it is reasonable to consider the possibility that this contraction affects space around galaxies by causing, locally, the expansion to be inhomogenous and anisotropic. This creates a halo of inhomogeneous space in which the central acceleration, at a given distance from the centre of the galaxy and towards it, is larger than in the case of no expansion.

I follow the possibility up to the point they say, "...larger than in the case of no expansion," which simply makes no sense to me. Plus, GR already accounts for what they're talking about: It yields the curvature at every point in the region around the galaxy. We all know the universe is not homogeneous in such regions. And I think most would agree the expansion is essentially negligible at such scales. I can't imagine what they're on about. A spoof article? Sometimes hard to tell.

loglo
2009-Sep-19, 04:05 PM
Spatial dilation eh? ... sounds like a bit of a stretch!