The Confrontation between General Relativity and Experiment
  The status of experimental tests of general relativity and of theoretical
frameworks for analyzing them are reviewed and updated. Einstein's equivalence
principle (EEP) is well supported by experiments such as the Eotvos experiment,
tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP
and of the inverse square law are searching for new interactions arising from
unification or quantum gravity. Tests of general relativity at the
post-Newtonian level have reached high precision, including the light
deflection, the Shapiro time delay, the perihelion advance of Mercury, the
Nordtvedt effect in lunar motion, and frame-dragging. Gravitational-wave
damping has been detected in an amount that agrees with general relativity to
better than half a percent using the Hulse-Taylor binary pulsar, and a growing
family of other binary pulsar systems is yielding new tests, especially of
strong-field effects. Current and future tests of relativity will center on
strong gravity and gravitational waves.
