Freiburg 2008 – scientific programme

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GR: Fachverband Gravitation und Relativitätstheorie

GR 14: Poster

GR 14.5: Poster

Monday, March 3, 2008, 08:00–20:00, Foyer KGI

How strong is the evidence for accelerated expansion? — •Marina Seikel and Dominik J. Schwarz — Universität Bielefeld

We test the present expansion of the universe using supernova type Ia data without making any assumptions about the matter and energy content of the universe or about the parameterization of the deceleration parameter. Using two different SN Ia data sets, two different fitting methods and two different calibrations, we observe large systematic effects. Nevertheless, the null hypothesis that the universe never expanded accelerated can be rejected at a high confidence level. The same test can be done in a calibration-free way, i.e. without assuming certain values for the Hubble constant and the absolute magnitude of the supernovae. But in this case the obtained evidence for acceleration is weaker than that obtained by the previous test.