Isolated Atoms
Atomic physics always considers atoms in isolation. Atomic models will consist of a single nucleus that may be surrounded by one or more bound electrons. It is not concerned with the formation of molecules (although much of the physics is identical), nor does it examine atoms in a solid state as condensed matter. It is concerned with processes such as ionization and excitation by photons or collisions with atomic particles.
While modelling atoms in isolation may not seem realistic, if one considers atoms in a gas or plasma then the time-scales for atom-atom interactions are huge in comparison to the atomic processes that are generally considered. This means that the individual atoms can be treated as if each were in isolation, as the vast majority of the time they are. By this consideration atomic physics provides the underlying theory in plasma physics and atmospheric physics, even though both deal with very large numbers of atoms.
Read more about this topic: Atomic Physics
Famous quotes containing the words isolated and/or atoms:
“The improved American highway system ... isolated the American-in-transit. On his speedway ... he had no contact with the towns which he by-passed. If he stopped for food or gas, he was served no local fare or local fuel, but had one of Howard Johnson’s nationally branded ice cream flavors, and so many gallons of Exxon. This vast ocean of superhighways was nearly as free of culture as the sea traversed by the Mayflower Pilgrims.”
—Daniel J. Boorstin (b. 1914)
“No imperfection in budded mountain,
Valleys breathe, heaven and earth move together,
daisies push inches of yellow air, vegetables tremble,
green atoms shimmer in grassy mandalas,
sheep speckle the mountainside, revolving their jaws with empty eyes,
horses dance in the warm rain,”
—Allen Ginsberg (b. 1926)