Evolution of radiation energy density
Matter and energy density evolve differently with redshift
Plot of matter and energy density evolution
Extension of inverse square law
Distance in terms of redshift and cosmological parameters: the Mattig equation
Use of standard candle in this equation
An example of how observed magnitudes of standard candles change with redshift for different cosmological models (values of Omega)
Other limits on the value of Omega from measurements of M/L ratio of galaxies, clusters, etc.
The details: question on large project with SNIa at high redshifts
