begins with the everyday physical world around us—the
blue of the sky, the colors of the rainbow, the fall of an
apple, the motions of the moon. What’s happening here?
Why do things work this way?
Physics goes on to give us many answers—along with
a rich and detailed account of things like force, motion, gravity, heat, light, electricity and magnetism:
the mechanisms that actually give rise to the everyday world.
But of course, physics doesn’t end there. Once you
start asking about the fall of an apple, there’s no
turning back. Each question leads to the next, until you
finally find yourself probing into the deepest secrets of
matter, energy, space—even time itself. What are they?
How do they really work? And where is the deep,
unifying principle that can help us truly understand them?
The quest to answer these questions has led physicists
on a long journey inward, first to the structure of the atom,
then to the powerful and dangerous forces inside the atomic
nucleus, and more recently to a bewildering array of “subatomic” particles
that they’ve christened with names like quark, gluon
and lepton. The quest has also led physicists on
a long journey outward, to studies of how the stars shine,
how black holes behave, how galaxies form, and how the universe
is expanding. And now, ironically enough, the journey inward
and the journey outward seem to be leading physicists to
the same place. The physics of the tiniest particles turns
out to be intimately intertwined with the universe as a whole,
and how the Big Bang brought it all into being some 13.7
billion years ago.
Back on the human scale, meanwhile, physics continues to
be an intensely practical kind of science. Among the many
modern technologies coming out of physics research are x-ray
machines, radio, radar, lasers, the Global Positioning System,
superconductivity, MRI scans and—through fundamental
studies in solid-state physics—the microchip. Today,
moreover, with their work in areas such as Bose-Einstein
condensates and quantum computation, physicists are laying
the groundwork for still newer generations of technology.
The National Science Foundation (NSF) has nurtured physics
in all these endeavors, from individual laboratories at the
universities to massive detectors at the big particle accelerators.
Indeed, along with agencies such as the Department of Energy,
NSF is one of the leading sources of support for physics
research in the United States. And, NSF is a major
source of support for the rising generation of students in
physics—the generation that will soon be joining in
the attack on the field’s greatest challenges: