Black Holes

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Black Holes

• Shannon Schmoll
• University of Washington
• Department of Astronomy

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Special and General Relativity

• SPECIAL RELATIVITY
• Nothing Can Travel Faster than the speed of
  light, 300,000,000 km/s
• GENERAL RELATIVTY
• Extension to SR that includes a theory on
  gravity
• Explained why its the only force that acts
  instantaneously

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Gravity in General Relativity
Gravity is a warp in space-time caused by
mass MORE MASS MORE WARP MORE PULL TO FALL
IN
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SoWhat is a Black Hole ?
First what its not
A HOLE!
IT IS A lot of mass pushed into a itty-bitty
amount of space
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Why are Black Holes Black?
The Escape Velocity of the black hole is greater
than the speed of light
Things on earth can escape with a certain velocity
V gt 11.2 km/s
V gt c
V lt 11.2 km/s
V lt c
Wheeler coined the term black hole in 1969
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What are Black Holes Made Of?
Most Black Holes in the universe are made of
collapsed stars
ANYTHING with mass can be a Black Hole! Just
make it small enough using the Schwarzchild
Radius
2GM
Rs

c2
e-
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Where Can Black Holes be Found?
In the Center of our Home, the Milky
Way. Sagitarius A
In the Center of Other Galaxies! Usually in the
form of Active Galatic Nuclei or Quasi-Stellar
Radio Sources

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And
Coming Soon to Earth! With the Large Hadron
Collider at CERN, opening in 2007 in Geneva

• LHC Facts
• Circular Particle Accelerator
• 27 km Circumference
• Will run 4 experiments including creating black
  holes smaller than a proton

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What did we learn?

• Black Holes are not Holes, but compressed matter
• They cause gravitational forces so large that
  light cant escape their pull
• They can be made of anythingeven humans!
• They can be really tiny

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