In a surprising turn of events, two research teams recently found that the expansion of the universe is speeding up, not slowing down. Scientists attribute this acceleration to repulsive gravity — pushing matter apart rather than pulling it together — from "dark energy," a hidden force that accounts for two-thirds of all matter and energy in the universe. A new class of large, wide-field telescopes would allow scientists to explore this mysterious force, says a new report from the National Research Council of the National Academies. The report maps out a new cross-disciplinary, interagency research strategy for physics and astronomy to answer the most profound questions about the cosmos in the coming decades.
Exploring the properties of dark energy through wide-field telescopes located in space and on the ground may help scientists predict the eventual fate of the universe and acquire fundamental information about the nature of matter, space, and time. They could view a thousand times more of the sky, collect data faster than currently possible, and study how dark energy is affecting the expansion rate of the universe. Supernovas — incredibly bright phenomena that result from the explosion of a star — would be used as cosmic distance markers. The development of these telescopes and other projects would require interagency cooperation by the U.S. Department of Energy, NASA, and the National Science Foundation so resources could be better focused, the committee added.
"Recent advances made by physicists in understanding matter, space, and time and by astronomers in understanding the universe as a whole have paved the way to answer the really big questions," said Michael Turner, chair of the committee that wrote the report, and chair, department of astronomy and astrophysics, University of Chicago, Ill. "To make further progress, we must develop a research agenda that focuses on physicists and astronomers doing collaborative projects rather than working separately."
A research and development program should also be initiated to begin planning for an unmanned space mission to study the polarization of radiation left over from the big bang. This research could allow scientists to better understand the birth of the universe by detecting the effects of initial ripples in the fabric of space-time. The existence of these tiny space-time ripples is presumed by the cosmic inflation theory, which is the favored model by scientists to explain the initial, rapid stage of the universe’s growth from its earliest moments to an entity full of galaxies, clusters of galaxies, voids, and great walls of galaxies.
High priority also should be given to constructing a deep underground laboratory, the committee said. Its depth would allow scientists to conduct experiments that are impossible to undertake in a traditional laboratory because of the constant interference from particles hitting Earth from outer space. A wide variety of measurements indicate that the universe contains more matter than is visible through telescopes. The presence of this additional mass, known as dark matter, is inferred through its gravitational influence on the motion of visible objects, such as stars and galaxies. Scientists can see the effects of dark matter, but its nature is a mystery. Some of the research to detect the makeup of dark matter needs to be done deep underground, at depths approaching several thousand feet. The report also highlighted the benefits of an underground laboratory to cutting-edge research on elementary particles called neutrinos and on the stability of the proton.
The study was funded by NASA, U.S. Department of Energy, and the National Science Foundation. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science and technology advice under a congressional charter. A committee roster follows.
Read the full text of Connecting Quarks with the Cosmos: Eleven Science Questions for the New Century for free on the Web, as well as more than 1,800 other publications from the National Academies. Printed copies are available for purchase from the National Academy Press Web site or by calling (202) 334-3313 or 1-800-624-6242. Reporters may obtain a pre-publication copy from the Office of News and Public Information (contacts listed above).
[This announcement and the report are available at http://national-academies.org]
NATIONAL RESEARCH COUNCIL
Division on Engineering and Physical Sciences
Board on Physics and Astronomy
Committee on the Physics of the Universe
Michael S. Turner* (chair)
Scientist II
Fermi National Accelerator Laboratory,
and Professor
Department of Physics, and
Professor and Chair
Department of Astronomy and Astrophysics
University of Chicago
Chicago
Eric G. Adelberger*
Professor
Experimental Nuclear Physics and Astrophysics
University of Washington
Seattle
Arthur I. Bienenstock
Professor
Synchrotron Radiation Laboratory
Department of Applied Physics and Department of Materials Science and Engineering
Stanford University
Stanford, Calif.
Roger D. Blandford
Richard Chace Tolman Professor of Theoretical Astrophysics
Division of Physics, Mathematics, and Astronomy
California Institute of Technology
Pasadena
Thomas K. Gaisser
Professor
Bartol Research Institute
University of Delaware
Newark
Fiona Harrison
Assistant Professor of Physics and Astronomy
California Institute of Technology
Pasadena
John P. Huchra*
Professor of Astronomy
Harvard University, and
Senior Astronomer
Smithsonian Astrophysical Observatory
Cambridge, Mass.
John C. Mather*
Project Scientist
Next Generation Space Telescope, and
Senior Astrophysicist
NASA Goddard Space Flight Center
Greenbelt, Md.
John Peoples Jr.
Director
Sloan Digital Sky Survey, and
Senior Scientist II
Fermi National Accelerator Laboratory
Batavia, Ill.
Helen R. Quinn
Theoretical Physicist
Stanford Linear Accelerator Center
Stanford, Calif.
R.G. Hamish Robertson
Professor
Department of Physics
University of Washington
Seattle
Bernard Sadoulet
Professor of Physics, and
Director
Center for Particle Astrophysics
University of California
Berkeley
Frank J. Sciulli
Professor of Physics
Nevis Laboratories
Columbia University
Irvington, N.Y.
Harvey D. Tananbaum
Director
Chandra X-Ray Center
Smithsonian Astrophysical Observatory
Cambridge, Mass.
J. Anthony Tyson*
Distinguished Member of the Technical Staff
Optical Physics Research Department
Bell Laboratories
Lucent Technologies
Murray Hill, N.J.
Frank A. Wilczek*
Herman Feshbach Professor of Physics
Center for Theoretical Physics
Massachusetts Institute of Technology
Cambridge
Clifford M. Will
Professor and Chair
Department of Physics
Washington University
St. Louis
Bruce D. Winstein*
Samuel K. Allison Distinguished Service Professor
Department of Physics, and
Enrico Fermi Institute
University of Chicago
Chicago
Edward L. Wright
Professor
Department of Astronomy
University of California
Los Angeles
RESEARCH COUNCIL STAFF
Joel Parriott
Study Director
* Member, National Academy of Sciences