From boud at astro.uni.torun.pl Thu Sep 30 12:26:59 2010 From: boud at astro.uni.torun.pl (Boud Roukema) Date: Thu, 30 Sep 2010 12:26:59 +0200 (CEST) Subject: [Cos-top] half-turn space analysis; new spherical 3-manifolds ? Message-ID: hi cosmic topologists, Today we have *two* cosmic topology articles on arXiv on the same day! (1) http://arxiv.org/abs/1009.5880 Cosmic microwave anisotropies in an inhomogeneous compact flat universe Authors: R. Aurich, S. Lustig This shows that the half-turn space E_2 also seems to provide a nice fit, at least with the S_60deg statistic, to the WMAP 7yr data, and it even seems to be a bit better than T^3. (2) http://arxiv.org/abs/1009.5825 Multipole analysis in cosmic topology Authors: Peter Kramer This seems to claim that the author has found 3 new spherical 3-manifolds, "N8, N9, N10". It's not clear to me if he claims that they can be given constant curvature, but maybe it's obvious to someone who knows the mathematics a bit better. i had thought that the constant curvature spherical 3-manifolds were already completely classified. Are N8, N9, and N10 new constant-curvature spherical 3-manifolds, in addition to those in Gausmann et al. 2001 http://arxiv.org/abs/gr-qc/0106033 ? cheers boud