Timeline
Important Events in Cosmology
| Event | Time $t$ | Redshift $z$ | Temperature $T$ |
|---|
| EW phase transition | 20 ps | $10^{15}$ | 100 GeV |
| QCD phase transition | 30 µs | $10^{12}$ | 150 MeV |
| Neutrino decoupling | 1 s | $6 \times 10^9$ | 1 MeV |
| $e^+ e^-$ annihilation | 6 s | $2 \times 10^9$ | 500 keV |
| BBN | 3 min | $4 \times 10^8$ | 100 keV |
| Matter-radiation eq. | 60 kyr | 3400 | 0.75 eV |
| Recombination | 260–380 kyr | 1100–1400 | 0.26–0.33 eV |
| Photon decoupling | 380 kyr | 1000–1200 | 0.23–0.28 eV |
| Reionization | 100–400 Myr | 11–30 | 2.6–7.0 meV |
| Matter-Λ equality | 9 Gyr | 0.4 | 0.33 meV |
| Present | 13.8 Gyr | 0 | 0.24 meV |
docs