Supernovae and Cosmology

• Analyze lightcurves vs. redshifts for many Type 1a supernovae at redshifts z <2

• Observations of over 100 SN (over 7 years) by Perlmutter et al. and Schmidt et al. have showed that they are dimmer than would be expected if the Universe was expanding at a constant rate or slowing down (as was previously thought)

• This is evidence that some unknown “dark energy” is causing the Universe to fly apart at ever-increasing speeds.