Akademik Veri Yönetim Sistemi
DARK ENERGY: THEORIES, DEVELOPMENTS AND IMPLICATIONS, ss.111-126, 2010 (SCI-Expanded)
We test models of cosmology for the best estimates of important parameters, that is, for matter, dark energy(DE), spacetime(ST) and cold dark matter(CDM) within variants and special cases of the Friedman-Robertson-Walker(FRW) approximation We use the largest available collection of supernovae la data(SNe la), 307 SNe la along with 69 data pairs reported from gamma ray bursts(GRB) and our present situation for a total of 377 data pairs extending back perhaps 10 billion light years Modeling with this large set allows better definition of the limits of DE, CDM and ordinary matter than previously While the ancient GRB data are quite noisy they do allow better estimates of the fitted curve asymptotes towards singularity than without The results from models employing the commonly used luminosity distance moduli(log) versus redshift data slightly prefer the DE model with H(o) of 70 2 +/- 0 6 km/s/Mpc at a normalized matter density, Omega(m), of 0 34 with significant negative spacetime (ST) curvature The best fit calculation for the model without DE presents a much lower matter density(0 10 +/- 0 01) and a very slow Universe expansion rate(41 4 +/- 3 2 km/s/Mpc) When tests were made using the actual distances(Mpc) versus frequency decline nu(o)/nu(e) data, which is the preferred method not relying too heavily on the great errors from far distance emissions(some standard deviations are many thousand Mpc), the flat DE model presents the worst fit of all models with H(o) of 75 4 +/- 0 7 km/s/Mpc at Omega(m) of 0 12 +/- 0 02 Most interestingly, the two best fits present Omega(Lambda) of 1 03 and 0 68 with significant ST curvature These solutions suggests a Universe consisting primarily of DE with abundant ST We suggest astronomers cease using the luminosity distance moduli from distant emissions for modeling cosmology and present results from models based on distance estimates vs redshift or frequency decline At least an order magnitude more and better astronomical data are required to unequivocally choose the best FRW model to refine for further work in cosmology Our results suggesting a Universe with excessive DE should exhibit open or negative curvature might foster some interesting theoretical models in the near future FRW models with the largest collection of SNe and GRB data tell us the Universe is not flat