Timeline of the Universe - Standard Model

Time since 0EventDescription Temperature
15 x 109 yrsNow Galaxies, stars, planets, and us3 K
109 yrs ?Galaxy formation bulges and halos of normal galaxies form20 K
106 yrsMicrowave Background recombination - transparent to photons3000 K
3 minNucleosynthesislight elements formed 109 K
6 secElectron-Positron pairscreation of electrons 6 x 109 K
2 secNeutrinos decouplecreation of neutrino background 1010 K
2 x 10-6 secProton-Antiproton pairs creation of nucleons 1013 K
2 x 10-10 secElectroweak unification E-M and weak force same1015 K
10-35 sec ?Inflationuniverse exponentially expands by 1026 1027 K
10-35 secGrand Unification E-M/Weak and Strong forces same1027 K
10-44 secQuantum Gravity Unification of all 4 forces 1032 K
< 10-44 secPlanck Era No concept of space or time? > 1032 K

from Lectures by S. Myers