Dark%20Energy:%20

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Dark Energy The Anti-GravityJoseph C.
Brossett
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Consequences of Dark Matter

• Consider the ratio presented before omega
  actual density / critical density
• If omega is lt 1, we live in an open universe with
  constant expansion.
• If omega is gt 1, we live in a closed universe
  that ends in a big crunch.
• If omega is 1, we live in a flat universe that
  eventually becomes static.

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Explaining Anti-Gravity

• In contrast with dark matter, dark energy hopes
  to explain the motion of galaxies.
• Galaxies, according to gravity, should move
  toward one another but do not.
• This effect is observed through contrasting red
  shifts with the brightness of supernovas.
• Dark energy is not necessarily energy in the
  conventional sense.

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Dark Energy Candidates

• Physicists ultimately do not know what causes the
  repulsion of galaxies.
• One candidate is a cosmological constant
  corresponding to some vacuum energy.
• Another is a proposed quintessential repulsive
  field pushing the galaxies apart.
• In the end, plans to look at more distant
  supernovae will hopefully give better estimates.

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Summary

• Dark energy plays a large role in the ending fate
  of our universe.
• Dark energy, unlike dark matter, is a phenomena
  to explain the motion between galaxies
  (anti-gravity).
• Essentially, dark matter and dark energy dominate
  the universe on large scales.
• Unfortunately, scientists really are not sure
  what dark energy is since it violates current
  laws.