Andrew E. Lange

Laureates 2009 - 2009 Past Astrophysics-History of the Universe

Andrew E. Lange is Goldberger Professor of Physics at California Institute of Technology, Pasadena, California. Prof. Lange is known for the discovery of the large-scale spatial geometry of the universe
being spatially flat, of its total mass-energy density having a "critical"
value and for major byproducts of this discovery. He confirmed the
existence of a negative-pressure dark energy pervading the universe;
provided evidence for an inflationary epoch at the beginning of
the universe, and measured the Universe's mean density, matter
density and other cosmological parameters.

Together with Paolo De Bernardis, (and parallel with Paul Richards' MAXIMA-1 experiment) Professor Lange led the BOOMERanG experiment which measured the angular sizes and amplitudes of the first few acoustic peaks in the cosmic microwave background radiation. These results led Lange and colleagues to deduct the Universe's geometry and to make their byproduct discoveries.

The publication of the BOOMERanG and MAXIMA data in 2000 provided the first undisputed
evidence that the Universe has a flat geometry. Additional analysis of the data implied that ordinary
matter makes a small fraction of the cosmic mass density (5% at the present time). These results
have been confirmed subsequently and carry important implications for fundamental physics.
The nature of most of the cosmic matter (known as "dark matter") is actively being explored,
and the flat geometry of the Universe is believed to have originated from an early epoch of
inflation, during which space curvature was erased by a prolonged period of vast expansion.

Prof. Lange also developed (with James Bock) the spiderweb bolometers that made BOOMERanG's
and MAXIMA-1's measurements possible, and that underlie other major cosmological
and astronomical projects and instruments.

Prof. Lange is a member of the American Academy of Arts & Sciences and the National Academy
of Sciences, and a fellow of the American Physical Society. His honors include the Balzan Prize
in Observational Astronomy & Astrophysics. Prof. Lange is a Leverhulme Fellow, Cardiff, Wales;
and a California Scientist of the Year (co-recipient).