Two years ago, the National Research Council (NRC) laid out 11 key
scientific questions at the intersection of physics and astronomy in
a report entitled "Connecting Quarks to the Cosmos" (see FYIs
#67 and #68,
2002). Earlier this year, in response, an interagency working group
of the National Science and Technology Council (NSTC) released a prioritized
strategic plan for efforts across several government agencies to address
those 11 questions. Exploring the nature of dark energy receives high
priority in the new report. Other areas considered ripe for "immediate
investment" are the study of dark matter, neutrinos, proton decay
and the nature of gravity, while longer-term objectives include research
into the heavy elements, nuclear astrophysics, the birth of the universe,
high density and high temperature physics and high energy cosmic ray
The Bush Administration's emphasis on setting milestones and measuring
results of federal programs, spelled out in the President's Management
Agenda, has led to a plethora of recent roadmaps and strategic planning
documents for federal R&D investments. Some of these documents,
like a report by a High Energy Physics Advisory Panel subpanel on long-range
planning (see FYI
#12, 2003), address only a specific discipline. Others, like
the DOE Office of Science 20-year facilities roadmap (see FYI
#150, 2003), span a broader range. The Interagency Working Group
relied on many of these previous DOE, NSF and NASA planning documents
for input as it determined what projects, facilities, and facility upgrades
would be needed to address the 11 questions of the NRC report.
The new report, entitled "The Physics of the Universe: A Strategic
Plan for Federal Research at the Intersection of Physics and Astronomy,"
is available at www.ostp.gov/html/physicsoftheuniverse2.pdf.
According to OSTP Director John Marburger in a February 2004 letter
accompanying the report, it represents "a new approach for coordinating
and prioritizing research programs across the government to explore
an emerging scientific frontier." The main participating agencies
are DOE, NSF and NASA, although NIST and the National Nuclear Security
Administration (NNSA) also receive mention.
The NSTC Interagency Working Group on the Physics of the Universe assessed
priorities based on the potential for scientific advancement, the timeliness
or urgency of each question, the technical readiness of projects, and
the need to fill gaps in the suite of projects to address each question.
The group "focused its work on the large-scale projects needed
to support research activities aimed at understanding the physics of
the universe," but noted that "concomitant investments in
theory, simulation, data archiving, and user groups are essential"
as well. It did not address cost and budgeting issues, nor how these
projects fit in with goals, projects and facilities in other areas of
physics or astronomy.
A summary of the report's recommendations in priority order, divided
into near-term and longer-term efforts, follows. In the report, each
recommendation is accompanied by a detailed discussion of the scientific
question, relevant agency projects and proposals, findings that provide
justification for the recommendations, and in many cases a suggested
time frame for implementing the recommendation.
READY FOR IMMEDIATE INVESTMENT, DIRECTION KNOWN
Three projects to investigate Dark Energy are recommended: a still-to-be-defined
NASA/DOE Joint Dark Energy Mission (JDEM); a study of "the weak
lensing produced by Dark Matter" by a ground-based Large-aperture
Synoptic Survey Telescope (LSST); and observations of galaxy clusters
by space-based X-ray and ground-based Cosmic Microwave Background (CMB)
Dark Matter, Neutrinos, and Proton Decay:
NSF and DOE should collaborate to "identify a core suite of physics
experiments" for research into Dark Matter, neutrinos, and proton
decay; and NSF should take the lead on conceptual development and formulation
of a scientific roadmap for an underground laboratory facility.
Two efforts are recommended: enhanced numerical relativity research
for more accurate simulation of gravitational wave sources; and "the
timely upgrade of the Laser Interferometer Gravitational Wave Observatory
(LIGO) and execution of the Laser Interferometer Space Antenna (LISA)
NEXT STEPS FOR FUTURE INVESTMENTS
Origin of Heavy Elements:
The report calls for DOE and NSF to develop roadmaps for the proposed
Rare Isotope Accelerator (RIA), and for "the major components of
a national nuclear astrophysics program."
Birth of the Universe:
DOE, NSF and NASA should jointly develop "a roadmap for decisive
measurements" of cosmic microwave background polarization.
High Density and High Temperature Physics:
NSF, DOE, NASA and NIST should generate a roadmap for major components
of a "balanced, comprehensive" national high energy density
physics program; DOE and NSF should develop a roadmap for upgrading
the luminosity and maximizing the impact on high energy density physics
of the Relativistic Heavy Ion Collider (RHIC); and at least one of NNSA's
major compression facilities should include a high-energy, high-intensity
laser capability "to observe and characterize the dynamic behavior
of high-energy-density matter."
High Energy Cosmic Ray Physics:
DOE and NSF should work to "ensure that the Pierre Auger southern
array [under construction in Argentina] is completed" and review
its results to "consider plans for a possible northern array."