| Time since 0 | Event | Description |
Temperature |
|---|
| 15 x 109 yrs | Now |
Galaxies, stars, planets, and us | 3 K |
| 109 yrs ? | Galaxy formation |
bulges and halos of normal galaxies form | 20 K |
| 106 yrs | Microwave Background |
recombination - transparent to photons | 3000 K |
| 3 min | Nucleosynthesis | light elements formed
| 109 K |
| 6 sec | Electron-Positron pairs | creation of electrons
| 6 x 109 K |
| 2 sec | Neutrinos decouple | creation of neutrino
background | 1010 K |
| 2 x 10-6 sec | Proton-Antiproton pairs |
creation of nucleons | 1013 K |
| 2 x 10-10 sec | Electroweak unification |
E-M and weak force same | 1015 K |
| 10-35 sec ? | Inflation | universe
exponentially expands by 1026 | 1027 K |
| 10-35 sec | Grand Unification |
E-M/Weak and Strong forces same | 1027 K |
| 10-44 sec | Quantum Gravity |
Unification of all 4 forces | 1032 K |
| < 10-44 sec | Planck Era |
No concept of space or time? | > 1032 K |