Evolution and morphology of the galaxies

Sullivan2003 showed, with the determination of the morphology of the supernovæ of the analysis of perlmutter1999, that the results of cosmology after correction of factor of stretching remained identical for the two batches of supernovæ coming from spiral and elliptic galaxy.

It is has little close bench that the two types of galaxy correspond to respectively young galaxies (little chemical evolution) and older. They thus present, in theory, of the ages and the different metalicities. There still, no effect of evolution is detectable.

Lastly, riess1999 studied, starting from unlot of 22 close supernovæ, the correlation between the type of the galaxy and it $\Delta m_{15}$. The authors showed that there was well a correlation between the two. However, this correlation disappears when the corrections of 6.5 $\Delta m_{15}$ .

It thus seems, in the light of our current knowledge, that the effects of evolution do not make it possible to call in question the conclusions about the acceleration of the expansion.