Black Holes

1
Black Holes

• Dennis OMalley

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How is a Black Hole Created?

• A giant star (more than 25x the size of the sun)
  runs out of fuel
• The outward pressure of the nuclear fusion ceases
• The gravity of the star forces it to collapse
  into itself after an explosion
• The mass of the star condenses to its smallest
  possible size
• Central Singularity
• The gravity is so strong that nothing, not even
  light, can escape
• Therefore, black holes cannot be seen by visible
  light

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The Anatomy of a Black Hole

• The event horizon is the edge where particles
  outside can escape and particles inside cannot
• The accretion disk is gas on the outside of the
  black hole that forms a rapidly rotating disk
• Most doesnt fall in so not very much energy is
  created from the destruction/absorption of the
  gas
• The area outside the black hole shows space as
  distorted, which is caused by the high gravity
  bending light that passes outside the event
  horizon
• There are infinitely many images of the stars
  behind the black hole they are distorted as the
  light from the stars orbit the black hole
• Gravitational Lensing

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Theories

• New computer diagrams have black holes not being
  created by explosion and collapse, just collapse
• The center of the milky way galaxy has a large
  black hole
• Originally discovered by radio waves
• Could be acting as a center of gravity for our
  galaxy
• Adaptive optics uses infrared to see many stars
  circling it very fast
• Some astronomers believe every galaxy has a
  supermassive black hole at its center

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Theories

• Many black holes are paired up from when galaxies
  passed closely by
• The galaxies combine and the black holes orbit
  around each other
• Their orbits are reminiscent of how protons and
  neutrons act in an atom
• Scientists are trying to connect quantum
  mechanics of atoms to the most massive objects in
  the universe black holes
• They eventually fall into one another
• Become a single, larger black hole
• Violent, would send gravitational ripples through
  space-time

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Theories

• Tiny particles that barely exist could create
  Hawking Radiation
• Particles come into existence in pairs
• End existence by coming together after a moment
• If they came into existence on the event horizon,
  one may stay in existence
• The one to survive outside the event horizon
  would become real and emit light
• That could allow us to see black holes

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Theories

• The conservation of information principle says
  that every ounce of material a black hole
  absorbs, it should radiate an equivalent amount
  of energy out of its event horizon
• Black holes may defy that principle and destroy
  the matter altogether

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Theories

• An outside observer would see something fall into
  a black hole in slow motion then frozen in time
  at the event horizon
• Einsteins theory of relativity says that a black
  hole would distort space and time

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Could I Orbit A Black Hole?

• You need to be traveling at escape velocity
• Similar to escaping the earths gravity into
  space, just more intense

10
Wormhole?

• Maybe, however we may never know
• Light from a black hole will never reach us
• Gets sucked in
• Researchers/probes could never communicate back
  if they entered one
• Gravity would render them useless by crushing
• Allow time travel? Travel to another dimension?
• That would be cool

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Personal Questions

• If black holes absorb all this matter, where does
  it go?
• Condensed into central singularity of the black
  hole?
• If so, how much matter can the central
  singularity contain?
• Was the big bang a black hole exploding after the
  central singularity reached its breaking point?