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[astro-ph/0511628] Recent Supernovae Ia observations tend to rule out all the cosmologies
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Authors:R. G. Vishwakarma (Zacatecas University)
Abstract:Dark energy and the accelerated expansion of the universe have been the direct predictions of the distant supernovae Ia observations which are also supported, indirectly, by the observations of the CMB anisotropies, gravitational lensing and the studies of galaxy clusters. Today these results are accommodated in what has become the `concordance cosmology': a universe with flat spatial sections t=constant with about 70% of its energy in the form of Einstein's cosmological constant \Lambda.
However, we find that as more and more supernovae Ia are observed, more accurately and towards higher redshift, the probability that the data are well explained by the cosmological models decreases alarmingly, finally ruling out the concordance model at more than 95% confidence level. This raises doubts against the `standard candle'-hypothesis of the supernovae Ia and their use to constrain the cosmological models.
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John Middleditch

Joined: 23 Aug 2006
Posts: 3
Affiliation: Los Alamos National Laboratory

PostPosted: November 22 2006  Reply with quote

Further re: SN-less GRB:
One degree off axis at 24-light days gives a delay near 200 s. For
a SN-less long-duration/soft spectrum GRB, there has to be
just enough polar overlayer to soften its spectrum (as all GRBs must
start as hard/short), but not enough produce much 56Ni by
burn around the non-polar regions. This is an important clue
about a mechanism we'll be spending the first half of this
century unravelling. Would be too much to ask that an NS-NS
merger produced a long/soft GRB!

Re: rotation in SN Ia 2003fg suggested by Howell to avoid DD
hypothesis: desperation.
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Ned Wright

Joined: 29 Nov 2006
Posts: 1
Affiliation: UCLA

PostPosted: November 29 2006  Reply with quote

R G Vishwakarma wrote:
However, taken at their face values, the only apparent prediction of the WMAP observations is a flat geometry

The CMB does not say the geometry is flat. It says ellpk is 220, and it gives ωb and ωm (=Ωm*h2), the index ns, the optical depth and the amplitude. Omega_m = 1.3, Omega_DE = 0 (and Ho = 32) is quite consistent with the CMB.
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