Lecture 8: Warped Space

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Lecture 8 Warped Space
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Einsteins Theory of General Relativity (GR)

• The effects of gravity can be described in terms
  of curved space-time

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Recall a car moving round a bend undergoes
acceleration
Driver will feel a centrifugalforce pushing him
outwards
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Similarly

• When space-time is curved, particles moving in it
  experience an acceleration
• By the equivalence principle, we interpret these
  particles as being affected by the force of
  gravity

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General Relativity (contd)

• Geometry of space-time is curved by matter in the
  space-time
• On the other hand, the curvature of space-time
  determines how the matter will move

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Imagine Earth as a ball on a rubber sheet
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Experimental Tests of GR

• Bending of light
• Gravitational redshift
• Precession of Mercury
• Gravity waves

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Precession of Mercury

• Mercurys orbit is known to precess by 43
  arcseconds per century
• Newtonian gravity could not explain this, but GR
  is able to!