title: Phonon dynamics.
abstract: An atomic lattice in its ground state is excited by the rapid displacement and release of an atomic constituent. The time dependence of the energy transfer to other constituents is studied by using a phonon dispersion relation that is linear in frequency and propagation vector components.
authors.affiliation: Department of Physics, University of California, Los Angeles, CA 90024, USA.
authors.forename: J
authors.initials: J
authors.lastname: Schwinger