  During its early evolution the Universe provided a laboratory to probe
fundamental physics at high energies. Relics from those early epochs, such as
the light elements synthesized during primordial nucleosynthesis when the
Universe was only a few minutes old, and the cosmic background photons, last
scattered when the protons (and alphas) and electrons (re)combined some 400
thousand years later, may be used to probe the standard models of cosmology and
of particle physics. The internal consistency of primordial nucleosynthesis is
tested by comparing the predicted and observed abundances of the light
elements, and the consistency of the standard models is explored by comparing
the values of the cosmological parameters inferred from primordial
nucleosynthesis with those determined by studying the cosmic background
radiation.
