Professors Marc Kamionkowski and Andrew Lange
Caltech
 

 The Cosmic Microwave Background (CMB) provides a clear view
of the embryonic universe.   Gravitational instability of structure
in the early universe drove acoustic oscillations in the density of
the photon/baryon fluid.  These left their imprint on the CMB as
faint (~  30 ppm rms) temperature fluctuations on sub-degree scales.
The angular power spectrum of these fluctuations has long been
predicted to contain a harmonic series of tones or "acoustic peaks".
Roughly speaking, the position of the fundamental tone determines the
geometry of the universe; the relative amplitude and position of the
higher harmonics  determines its contents.  Several experiments have
recently achieved, for the first time, the fidelity and sensitivity
to detect the higher harmonics, marking the beginning of a new phase
of CMB research.  Analysis of the higher harmonics confirms that we
live in a universe composed of 5% baryonic matter, 30%
non-relativistic dark matter of unknow form and 65% "dark energy"
that is currently causing the expansion rate to accelerate.