The CMB Red Power Spectrum

The CMB power spectrum modeled with data from the WMAP (2006), ACBAR (2004), BOOMERanG (2005), CBI (2004), and VSA (2004) experiments.

Recent experiments have succeeded in measuring the CMB anisotropy at increasingly small angular scales. The resulting power spectrum is in effect a snapshot of the acoustic frequency modes at the time of decoupling. The structure of these modes is intrinsically connected to the physics of the early Universe.

Detailed study of the first peak reveals information about the geometry of space-time, namely that the Universe is very close to being flat. The ratio of odd to even peaks indicates the Universe's total baryon density while the location of the third peak yields clues about the density of dark matter.