Big Bang Timeline

Time Era Temperature Characteristics of the Universe
0 to 10-43 s Big Bang infinite infinitely small, infinitely dense 
Primeval fireball
1 force in nature - Supergravity
10-43 s Planck Time 1032 K Earliest known time that can be described by modern physics
2 forces in nature, gravity, GUT
10-35 s End of GUT 1027 K 3 forces in nature, gravity, strong nuclear, electroweak
Quarks and leptons form
(along with their anti-particles)
10-35 to 10-33 s Inflation 1027 K Size of the Universe drastically increased, by factor of 1030to 1040
10-12 s End of unified forces 1015 K 4 forces in nature, 
protons and neutrons start forming from quarks
10-7 s Heavy Particle 1014 K proton, neutron production
in full swing
10-4 s Light particle 1012 K electrons and positrons form 
100 s (a few minutes)
Nucleosynthesis era 109 - 107 K helium, deuterium, and a few other elements form
380,000 years Recombination (Decoupling) 3000 K Matter and radiation seperate
End of radiation domination, start of matter domination of the Universe
500 million yrs Galaxy formation 10 K galaxies and other large structures form in the universe
14 billion years
or so
Now 3 K You are reading this table, that's what's happening.