Possible interpretations of the magnitude-redshift relation for supernovae of type IA

Abstract

It has been shown by Riess et al. and Perlmutter et al. that the observed redshift-magnitude relation for supernovae of type Ia, which suggests that the deceleration parameter is negative, can be explained in a Friedmann model with a positive cosmological constant. We show that a quasi-steady state cosmology (QSSC) model can also fit the supernova data. Since most of the emphasis and publicity have been concentrated on explanations involving the Friedmann model, we show how a good Ðt can be obtained to the observations in the framework of the QSSC. Using this model, we show that absorption due to intergalactic dust may play an important role. This may explain why a few of the supernovae observed show large deviations from the curve determined by the majority of the data.