Name: ______________________________________
Era
#
Epochs:
Time After
Big Bang
Temp
Size
Forces Present
Main occurrences
Superforce: Gravity,
strong nuclear,
Weak, and
Electromagnetic all
together
No matter existed, only energy. Gravity splits away
at the end.
1
Planck
Immediately
after
10^40K
A single Atom
2
Grand Unified
Gravity and the
Grand Unified
Theory: strong
nuclear, weak, and
electromagnetic
10^36K
Strong nuclear breaks away
3
Radiation
Era
Inflationary
10^33K
Grapefruit
Fractions of
a second
Gravity, Strong
Nuclear, and
Electroweak
(electromagnetic and
weak)
4
All four forces finally split off. Higgs Boson particles
Electroweak
10^20K
5
Quark
10^16K
6
Hadron
7
The universe rapidly expands. Now has electrons,
quarks.
Lepton/Nuclear
1-100
seconds
Rapidly
doubling and
expanding in
size
Gravity, Strong
Nuclear,
Electromagnetic and
Weak
All atomic ingredients now present, but still too hot
and dense for subatomic particles to form
10^10K
Universe cools enough for quarks to form protons
and neutrons. Hadrons and anti hadrons destroy
each other.
10^9K
Protons and neutrons fuse and form nuclei: Helium
Era
#
1
Matter
Era
2
3
Epochs:
Atomic
Galactic
Stellar
Time After
Big Bang
50,000
Years
200 Million
Years
3 Billion
Years
Temp
Size
Forces Present
3,000K
Expanding
n/a
n/a
Close to
present and
still expanding
Gravity, Strong
Nuclear,
Electromagnetic and
Weak
Main occurrences
Elections fuse to nuclei which is Recombination,
they settle to ground state and release the photons
of the Cosmic Microwave Background that we still
see today
Elements make atomic clouds and these gas pockets
have enough gravity to allow clusters, which are the
seedlings of galaxies
Stars appear in galaxies
Ripple effect forms, other elements from H and He