  A redshift-luminosity distance relation in excellent agreement with
observations is calculated here for SNe 1a using the Yilmaz gravitational
theory. In contrast to the current conventional explanation based on general
relativity, the Yilmaz theory does not require a cosmological constant term
that implies the existence of "dark energy". The Yilmaz theory requires only
one parameter; a mean mass-energy density of the cosmos. The required value is
essentially the same as the critical density for a Friedmann-Robertson-Walker
cosmological metric. The Yilmaz theory therefore still requires the existence
of non-baryonic dark matter.
