The big bang didn’t create all the matter in the universe, it all existed already in a point that was infinitely small, infinitely dense and very very hot. The big bang was the explosion of the space, rather than the explosion of matter into a space (Which is where the earlier nail bomb analogy to explain expansion of the universe breaks down).
Thereafter the universe started to cool and after about a millionth of a second the fundamental particles, and their anti-particles, started to form in pairs out of what was probably a plasma soup. These are Quarks, Neutrinos, electrons and photons and are basically what everything else is made of. They then tear about annihilating with gay abandon in flashes of radiation.
More expansion of the space and more cooling and the protons and neutrons start to form at around a minute when the universe has cooled to about 300 billion Kelvin. This new lower temperature allows the formation of light atomic nuclei, but because the temperature and radiation energy is still to high stable atoms can’t form.
Expansion and cooling continues for about another 300,000 years before stable atoms start to form. This is also the point in the universe at which radiation and matter are decoupled. The radiation is whats now called the CMBR – Cosmic Background Microwave Radiation.
Star and Galaxy formation gets going when the universe is around 100 million years old, driven by an uneven distribution of matter caused by clumping of matter through gravitiational attraction in the early, hot, universe
So there you have the first 100 million years in 4 paragraphs….. there’s obviously a lot of the theory missing there but in a nutshell that’s the chronology
