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Big Bang
0 Seconds after the Big Bang
- Big Bang occurs
- creation of space and time -
Planck Epoch
0 to 10e-43 after the Big Bang
- planck is shortest possibly interval of time (so far)
- four fundamental forces (gravitation, electromagnetism, weak nuclear force, strong nuclear force), possibly all unified -
Grand Unification Epoch
10e-43 to 10e-36 seconds after the Big Bang
- three of the fundamental forces combine to form the electronuclear force
- gravity separates from the other three forces -
Inflationary Epoch
10e-36 to 10e-32 seconds after the Big Bang
- universe undergoes extremely rapid exponential expansion
- releases energy; universe is repopulated with new and hot particles -
Electroweak Epoch
10e-36 to 10e-12 seconds after the Big Bang
- strong force separates, leaving only electroweak force
- creation of large numbers of exotic particles -
Quark Epoch
10e-12 to 10e-6 seconds after the Big Bang
- weak force separates from electromagnetic forcce
- all four fundamental particles are now separated into their present forms
- universe is filled with quark-gluon plasma (particles) -
Hadron Epoch
10e-6 seconds to 1 second after the Big Bang
- universe cools
- hadrons (i.e. protons and neutrons) begin to form -
Lepton Epoch
1 second to 10 seconds after the Big Bang
- hadrons and anti-hadrons go through annihilation phase
- leptons and anti-leptons (particles) dominate the universe -
Period: to
Photon Epoch
10 seconds to 380,000 years after the Big Bang
- leptons and anti-leptons go through annihilation phase
- universe is dominated by photons (light particles) -
Radiation Era
10,000 years after the Big Bang
- radiation dominates the universe
- wavelengths of light, x-rays, radio waves, ultraviolet rays -
Matter Domination
70,000 years after the Big Bang
- cold, dark matter dominates the universe
- dense regions become denser; matter starts to clump together -
Recombination
377,000 years after the Big Bang
- density of universe falls; hydrogen and helium atoms begin to form
- initially ionized particles (no electrons); as universe cools, electrons are captured by ions and form neutral atoms
- photons can now travel freely (decoupling); go on to form cosmic microwave background (CMB) radiation -
Dark Ages
- photons do not emit visible light; universe is opaque and foggy as a result
- universe is transparent and neutral
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Period: to
Reionization
- gravitational collapse form first stars and quasars (starlike objects that emit massive ammounts of energy)
- emitted radiation reionizes (charges atomic particles of) surrounding universe
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Structural Formation
stars begin to ignite; matter clumps together to form planets; galaxies begin to form -
Formation of Solar Star System
between 8 to 9 billion years after the Big Bang, the Solar Star System forms -
Present Day
13.7 billion years after the Big Bang
