Transcript Timeline of the Universe

Timeline of the Universe
The Birth of the Universe Big Bang and Beyond
http://www.youtube.com/watch?v=zfZ7tokEwzg
The Age of the Universe
• NASA's Wilkinson Microwave Anisotropy
Probe (WMAP) project estimates the age
of the universe to be:
(13.75 ± 0.11) × 109 years.
“Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Sky Maps,
Systematic Errors, and Basic Results”, N. Jarosik, C. L. Bennett, J. Dunkley, B. Gold, M. R.
Greason, M. Halpern6, R. S. Hill, G. Hinshaw, A. Kogut, E. Komatsu, D. Larson, M. Limon,
S. S. Meyer, M. R. Nolta, N. Odegard, L. Page, K. M. Smith, D. N. Spergel, G. S. Tucker, J.
L. Weiland, E. Wollack, E. L. Wright, nasa.gov, 2011
The Distant Past
• 13.75 ± 0.11 billion years ago: Universe begins
with Big Bang
• 1 μsec~ 1 sec after the BB, protons and
neutrons formed
• 380,000 years after the BB, hydrogen nuclei
capture electrons, forming the first atoms
• 100 million years after BB: formation of first stars
• 600 million years after the BB: formation of first
galaxies
• 5 billion years ago: formation of the Sun
• 4.5 billion years ago: formation of the Earth start of geologic timescale
Four Interactions
Theory
Interaction mediator
Relative
Behavior Range
Magnitude
Chromo
-dynamics
Strong
gluon
interaction
1038
1/r7
1.4
x10-15
m
Electro
-dynamics
Electro
-magnetic
interaction
1036
1/r2
infinite
Flavor
-dynamics
Weak
W and Z
interaction bosons
1025
1/r5 to
1/r7
10-18 m
Geometro
-dynamics
Gravity
1/r2
infinite
photon
graviton 100
Timeline of the Subatomic Era
Era
Planck Epoch
Grand Unification
Epoch
Electro- Inflationary
Epoch
weak
Epoch
Quark Epoch
Time
Events
four fundamental forces — electromagnetism, weak nuclear force, strong
nuclear force and gravitation — all have the same strength
~10-43
10-43 ~10-36 s
10-36 ~10-32 s
gravitation begins to separate
The rapid expansion of space by factor of 1026 (size) or by 1078 (vol).
10-36~10-12 s strong force from the electroweak force
10-12~10-6
s
The fundamental interactions of gravitation, electromagnetism, the strong
interaction and the weak interaction have now taken their present forms
Hadron Epoch
10-6 ~1 s
protons and neutrons formed
Lepton Epoch
1 s ~10 s
leptons left
10 s~380,000 photons dominated the energy of the universe
yr
BB
Photon
Nucleosynt
Epoch
hesis
3~20 min
70,000 yr
result in 75%(mass) of H-1, about 25% He-4, about 0.01% of deuterium,
trace amounts of Li and Be and no other heavy elements.
the densities of non-relativistic matter (atomic nuclei) and relativistic
radiation (photons) are equal
Planck Epoch
• Named after Max Planck, in cosmology the Planck epoch is the
earliest period of time in the history of the universe, from zero to 1043 seconds (one Planck time), during which all four fundamental
forces were unified and elementary particles did not exist.
• Standard quantum mechanics says that it is meaningless to speak
of durations shorter than Planck time or distances shorter than one
Planck length, the distance light travels in one Planck time—about
1.616 × 10-35 meters. Accordingly, the history of the universe should
be measured, not from zero, but from one Planck time. Likewise, the
volume of the universe would start at one Planck length in diameter
rather than at zero, and, thus, there was never a singularity of
infinite density. As of 2006, there is no generally accepted theory
that unifies quantum mechanics and relativistic gravity. A future
complete theory may or may not allow more to be said about the
Planck epoch.
The mass fraction in various
isotopes vs time
from Burles, Nollett & Turner (1999).
Epoch of Nucleosynthesis
Helium Atom,
from wikipedia
About 380,000 years after the Big Bang the temperature of the
universe fell to the point where nuclei could combine with electrons
to create neutral atoms. As a result, photons no longer interacted
frequently with matter, the universe became transparent and the
cosmic microwave
background
radiation
was created.
BBN will
result in mass
abundances
of about 75% of H-1
about 25% He-4, about 0.01% of deuterium, trace (on th
order of 10-10) amounts of Li and Be and no other heavy
elements.
Timeline of Universe
Image from WMAP press release, 2006
Notable Scientists
Edwin Hubble (1889 –1953)
-detection of novae in the Andromeda galaxy, redshift and
expanding universe. Almost Nobel Prize Winner(shortly after his
death, Nobel committee recognized astrophysics is eligible for Nobel
prize ,1953)
George Gamow(1904-1968) & Ralph Alpher (1921– 2007)
-Big Bang theory
Alan Guth(1947-)-Inflationary theory
Fred Hoyle(1915– 2001)
- theory of stellar nucleosynthesis, rejection of Big Bang, rejection
of chemical evolution
Pyotr Kapitsa(1894-1984), Arno Penzias(1933-), Robert Wilson(1936-)
- discovery of cosmic microwave background radiation, Nobel Prize in
Physics (1978)