BBN: Theory vs Observations

• Predictions: Schramm plot (Cyburt, Fields, & Olive 2003,2008)
• Concordance

BBN: Implications

• baryon density
• dark matter: two kinds!
  • baryonic dark matter: e.g., hot gas in collapsed structures and intergalactic gas; MACHOs (well, probably not MACHOs)
  • non-baryonic dark matter

BBN in Light of the CMB

• Overview: BBN+CMB Schramm plot
• Standard BBN: Light element CMB predictions vs observations (CFO 2003)

Particle Dark Matter

Relic Species

• production in the early universe
• annihilation freezeout