Transcript Dark Matter and Dark Energy - Mid

Dark Matter and Dark Energy
By: Matt Tanaka
And Bryent Kaneshiro
Dark matter is matter
that is inferred to exist
from gravitational
effects on visible matter
and background
radiation
Its existence was
hypothesized because
of the discrepancies
between measurements
of the mass of galaxies
and clusters of galaxies
http://www.youtube.com
/watch?v=nJN2X3NrQ
It turns out there is
about 5 times more
material in clusters of
galaxies than what we
would expect from the
galaxies and hot gas we
can see.
It is undetectable by
emitted or scattered
electromagnetic
radiation or in other
words “invisible”
Dark matter was
discovered in 1933
from astronomer
Fritz Zwicky for
evidence of missing
mass.



Dark matter plays
a role on the
universes fate
The universe is
expanding
everyday.
Gravity is
dependent upon
the mass of the
universe.

If actual mass
density is greater
then critical mass
density, the
universe will
expand, slow, stop
and collapse back
on itself

If actual mass
density equals
critical mass, the
universe will
continue to expand
forever, but rate of
expansion will
slow more over
time.

If actual mass
density is less than
critical mass
density, the
universe will
continue to expand
with no change in
its rate of
expansion
Dark energy is a
hypothetical form of
energy that
permeates all of
space and tends to
increase the rate of
expansion of the
universe.
Dark energy
accounts for 70 % of
the total mass –
energy of the
universe.
http://www.youtu
be.com/watch?v=L
PoV_v7xL2w
2 forms of dark
energy.


cosmological
constant - a constant
energy density filling
space
homogeneously.
scalar fields-energy
density can vary in
time and space
Albert Einstein was
the first person to
realize that empty
space is not nothing.
The 1st to Proposed
the theory of
cosmological
constant.
"Dark
Matter." Wikipedia, the Free Encyclopedia. Web. 11 Jan. 2011.
<http://en.wikipedia.org/wiki/Dark_matter>.
"Dark
Energy, Dark Matter." NASA Science. 19 Aug. 2010. Web. 11 Jan.
2011. <http://science.nasa.gov/astrophysics/focus-areas/what-is-darkenergy/>.
"Dark
"What
Energy." Wikipedia, the Free Encyclopedia. Web. 11 Jan. 2011.
<http://en.wikipedia.org/wiki/Dark_energy>.
Is Dark Energy? | Space.com." Space, NASA Information & News |
Outer Space Flight Videos & Pictures | Astronomy, Solar System Images |
Space.com. Web. 11 Jan. 2011. <http://www.space.com/6619-darkenergy.html>.