In the first million years of the Universe, cosmic perturbations drive
sound waves into the cosmic plasma. These sound waves are seen in the
cosmic microwave background maps as the acoustic oscillations. We have
now detected the imprint of the acoustic phenomenon in the clustering
of nearby galaxies, thereby completing an important test of our theory
of gravitational structure formation. Moreover, because the sound
wave pattern has been seen both at low redshift in the galaxies and at
high redshift in the CMB, we can measure the relative distance to these
two very disparate redshifts. This yields a geometric demonstration of
the acceleration of the expansion rate of the universe.
Here are a bunch of relevant links.
Our analysis team has been supported by several grants from the National Science Foundation
as well as by the Sloan Foundation and NASA.