COSMOLOGICAL TIME DILATION USING TYPE IA SUPERNOVAE AS CLOCKS

Although there is little doubt at present that the redshift of distant galaxies is due to an expansion of the universe, we present in this p aper a direct confirmation for the cosmological expansion. This work i s based on the first results from a systematic search for high redshif t Type Ia supernovae. We discovered over twenty seven SNe, before or a t maximum light. In this paper we report on the first seven of these, with redshift z = 0.35 - 0.46. Type Ia SNe are known to be a homogeneo us group of SNe, to first order, with very similar light curves, spect ra and peak luminosities. In this paper we report that the light curve s we observe rue all broadened (time dilated) as expected from the exp anding universe hypothesis. Small variations from the expected 1 + z b roadening of the light curve widths can be attributed to a width-brigh tness correlation that has been observed for nearby SNe (z < 0.1). We show in this paper the first clear observation of the cosmological tim e dilation for macroscopic objects.