We compare the Hubble
diagram calculated from the observed redshift (RS)/magnitude (μ) data of
280 Supernovae in the RS range of z = 0.0104 to 8.1 with Hubble diagrams
inferred on the basis of the exponential tired light and the Lambda Cold Dark
Matter (ΛCDM) cosmological model. We show that the experimentally measured
Hubble diagram follows clearly the exponential photon flight time (tS)/RS
relation, whilst the data calculated on the basis of the ΛCDM model exhibit
poor agreement with the observed data.