Bahcall explores universe's 'dark side'
Posted April 4, 2008; 10:04 a.m.
Neta Bahcall, Princeton's Eugene Higgins Professor of Astrophysics, will deliver a lecture on "The Dark Side of the Universe" at 8 p.m. Tuesday, April 8, in A02 McDonnell Hall.
Bahcall will discuss surprising findings about the composition of the universe, which includes not only dark matter but also "dark energy" -- a form of energy that opposes the pull of gravity and causes the expansion of the universe to accelerate. She will discuss recent observations of clusters of galaxies, distant supernovae and the cosmic microwave background that provide evidence that the universe includes 5 percent "normal" matter, 20 percent dark matter and 75 percent dark energy -- much less matter than previously thought. These observations of the "dark side of the universe" suggest that it will keep expanding forever.
Bahcall is known for her work in cosmic cartography, divining the structure and properties of the universe on large scales from massive sets of data accumulated through deep surveys of the sky and with the Hubble Space Telescope. She has been a pioneer in developing innovative techniques to interpret astronomical data, including a statistical approach to understanding how giant clusters of galaxies are distributed in the universe. The determination of the mass density or total mass of the universe is among her most fundamental contributions to astrophysics.
The lecture, which is intended for a general audience, is designated as the annual Evnin Lecture sponsored by the Council on Science and Technology.