15.5: The Big Bang in Eras
To look at the development of the Universe through the Big Bang, astronomers have divided the development into steps or
eras
. These eras are our best scientific match to the data we currently have; they seem scientifically sensible. New data is being used to revise and heighten our understanding of these eras.
The generally accepted Big Bang Eras include:
- Planck
- Grand Unification Theory (GUT)
- Electroweak
- Particle
- Nucleosynthesis
- Nuclei
- Atoms
- Galaxies
A summary of the Big Bang events occurred in this order:
- Big Bang beginning – a bright and hot event →
- Planck Era ; initial energy →
- Elementary Particles – photons create particles and antiparticles →
- Inflation of the Universe →
- Four Forces become distinct (strong, weak, electromagnetic, and gravity) →
- Protons, Neutrons, Electrons, and Neutrinos formed →
- Hydrogen ions fusion into helium ions →
- Stable, Neutral Atoms formed →
- Protoclouds formed →
- Stars, stellar systems, galaxies formed →
- Life, Humans; today