The Wilkinson Microwave Anisotropy Probe (WMAP) has made an accurate
full-sky measurement of the microwave background temperature and
polarization fluctuations. These measurements probe
both the physics of the very early universe and the basic properties
of the universe today. The WMAP measurements rigorously test
our standard cosmological model and provide an accurate determination
of basic comological parameters (the curvature of the universe,
its matter density and composition). When combined with other
astronomical measurements, the measurements contrain the
properties of the dark energy and the mass of the neutrino.
The observations also directly probe the physics of inflation: the
current data imply that the primordial fluctuations were primarily adiabatic
and nearly scale invariant.