information:classification, structural:scholar_edition
Baryon acoustic oscillations

Peaks have been found in the correlation function (the probability that two galaxies will be a certain distance apart) at 100 h Mpc, (where h is the dimensionless Hubble constant) indicating that this is the size of the sound horizon today, and by comparing this to the sound horizon at the time of decoupling (using the CMB), we can confirm the accelerated expansion of the universe.