Saul Perlmutter
active c. 1959, Urbana, Illinois, USA
American astrophysicist who led the Supernova Cosmology Project, co-discoverer of the accelerating expansion of the universe.
At Berkeley, Perlmutter built techniques to find distant type Ia supernovae — 'standard candles' for measuring cosmic distances. In 1998 his team announced that distant supernovae were dimmer than expected: the universe is not slowing down but accelerating, implying a 'dark energy' making up roughly 70% of the cosmos. The rival High-Z team reached the same conclusion the same year.
Nobel-winning work
By measuring brightness and redshift of dozens of type Ia supernovae, Perlmutter's Supernova Cosmology Project inferred that cosmic expansion is speeding up — upending the cosmological model of the day. The discovery (matched by the Schmidt–Riess team) led to ΛCDM: a universe of ~5% ordinary matter, ~25% dark matter and ~70% dark energy.
Workplaces: Lawrence Berkeley National Laboratory, University of California, Berkeley
United States