Big Bang
Template:TOC-right The Big Bang is an important aspect of the theoretical model of the universe. The Big Bang means that essentially the universe began at Planck Time, 10-43 seconds, from a single point about 13.7 billion years ago, expanding at great speed to its current state. Prior to Planck Time, the Four Forces, strong, electromagnetic, weak and gravity, were united in one force.
At 10-35 seconds, the temperature of the Universe reached 1027 to 1028K and the initial inflation of the universe ended at 10-33 seconds.
The Universe continued to expand and its temperature dropped to about T=1013 K until 0.0001 seconds after the Big Bang. Antiprotons and protons annihilated each. For some reason, apparently most antimatter was annihilated but there were surviving protons and neutrons. There were also a very large number of photons per proton and neutron .
Eventually matter coalesced to form larger bodies, then stars and galaxies. The first stars formed about 100 million years after the Big Bang.
Unstable stars became supernovae, and when they exploded they spread all the elements from carbon, through through uranium throughout the Universe. Numerous galaxies then formed as dark matter, stars and gas coalesced and merged. Later, clusters of galaxies formed and eventually, the Solar System and Sun formed about 4.6 billion years ago.
The time now is 13.7 Gyr (billion years) after the Big Bang, and the temperature is T=2.725 K.
Notes
- ↑ Big Bang Models Hyperphysics, Georgia State University
- ↑ Fundamental Forces Hyperphysics, Georgia State University
- ↑ Brief History of the Universe Wright, Edward L. Astronomy, University of California, Los Angeles