The highest-energy particles accessible to us are produced by natural accelerators throughout the universe and arrive on Earth as high-energy gamma rays, neutrinos, and cosmic rays. A full understanding of how these particles are produced and accelerated could shed light on the unification of nature’s forces. The Southern Auger array in Argentina is crucial to solving the mystery of the highest-energy cosmic rays.
Discern the physical principles that govern extreme astrophysical environments through the laboratory study of high-energy-density physics. The committee recommends that the agencies cooperate in bringing together the different scientific communities that can foster this rapidly developing field.
Unique laboratory facilities such as high-power lasers, high-energy accelerators, and plasma confinement devices can be used to explore physics in extreme environments as well as to simulate the conditions needed to understand some of the most interesting objects in the universe, including gamma-ray bursts. The field of high-energy-density physics is in its infancy, and to fulfill its potential, it must draw on expertise from astrophysics, laser physics, magnetic confinement and particle beam research, numerical simulation, and atomic physics.
Realize the scientific opportunities at the intersection of physics and astronomy. The committee recommends establishment of an interagency initiative on the physics of the universe, with the participation of DOE, NASA, and NSF. This initiative should provide structures for joint planning and mechanisms for joint implementation of cross-agency projects.
The scientific opportunities the committee identified cut across the disciplines of physics and astronomy as well as the boundaries of DOE, NASA, and NSF. No agency has complete ownership of the science. The unique capabilities of all three, as well as cooperation and coordination between them, will be required to realize these special opportunities.
The Committee on the Physics of the Universe believes that recent discoveries and technological developments make the time ripe to greatly advance our understanding of the origin and fate of the universe and of the laws that govern it. Its 11 questions convey the magnitude of the opportunity before us. The committee believes that implementing these seven recommendations will greatly advance our understanding of the universe and perhaps even our place within it.