Radiation in the Universe

• theory: photon redshifts sketched on balloon analogy
• redshift recordholders:
  • QSO at z=7.085 (Mortlock+ 2011)
  • GRB at z=9.4 (Cucchiara+ 2011)
  • Ultra Deep Field evidence for galaxies at z~10 (Bouwens 2011)
  • Extreme Deep Field infrared evidence for a galaxy at z=11.9 (Ellis+ 2013)
• radiation energy density
• radiation pressure

The Cosmic Equation of State

Minimally Realistic(?) Cosmic Histories

• cosmic ingredients
• limiting cases: matter, radiation, curvature, Lambda domination