for their leadership of the Wilkinson Microwave Anisotropy Probe (WMAP) experiment, which has enabled precise determinations of the fundamental cosmological parameters, including the geometry, age and composition of the universe.
In 1967 Arno Penzias and Robert Wilson made the first definitive detection of 3 K microwave radiation from the sky. The radiation was soon confirmed as the redshifted afterglow from the creation of the universe. For this discovery Penzias and Wilson won the 1978 Nobel Prize in Physics. This Cosmic Microwave Background (CMB) radiation allows astronomers to probe the distribution of matter and energy at a time slightly less than 400,000 years after the Big Bang. Soon after its discovery, astronomers recognized that accurate measurements of the CMB could provide vital information regarding the structure and evolution of the universe. Many experiments have been done since then, confirming this vision. The 2006 Nobel Prize in Physics was awarded to John Mather and George Smoot for their measurements of the spectrum and anisotropy of the CMB with the Cosmic Background Explorer (COBE) experiment.
Launched in July 2001, the Wilkinson Microwave Anisotropy Probe (WMAP) has made an extraordinarily detailed, all-sky high-resolution map of the brightness of the cosmic microwave background. It is sensitive to temperature variations at the level of 1 part per million. By analyzing these tiny variations, the WMAP team, led by Bennett, Page and Spergel, has measured the fundamental cosmological parameters, including the geometry, age and composition of the universe to unprecedented precision. We now know that the universe is geometrically flat, its age is 13.75 ± 0.13 billion years, and that it is composed of dark energy (72.1 ± 1.5 %), dark matter (23.3 ± 1.3 %) and baryons (4.6 ± 0.1 %). The WMAP measurements have opened the era of precision cosmology and have had an enormous impact across astronomy, cosmology and physics.
How did the universe begin? What makes up the universe? Why does the sky look the way it does? Humankind has been asking these kinds of questions for millennia, but these questions are now subject to direct observational measurements. Measurements have revealed that we live in an expanding universe and that the expansion is becoming faster and faster.
It is now firmly established that our universe has been expanding and cooling for billions of years, ever since the Big Bang. To be precise, the Wilkinson Microwave Anisotropy Probe (WMAP) space mission has determined that the age of the universe is thirteen billion, seven hundred million years. This has been recognized by the Guinness Book of World Records as the most accurate determination of the age of the universe.
Professor Charles L Bennett was born in 1956. He received a PhD in Physics from the Massachusetts Institute of Technology in 1984. He is currently a Professor of Physics and Astronomy at the Johns Hopkins University and a Member of the United States National Academy of Sciences.
Professor Lyman A Page Jr was born in 1957. He received a PhD in Physics from the Massachusetts Institute of Technology in 1989. He is currently the Henry DeWolf Smyth Professor of Physics at Princeton University and a Member of the United States National Academy of Sciences.
Professor David N Spergel was born in 1961. He received a PhD in Astronomy from Harvard University in 1985. He is currently the Charles A Young Professor of Astronomy and Chair of the Department of Astrophysical Sciences of Princeton University and a Member of the United States National Academy of Sciences.
