Lecture 6: General Relativity

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Lecture 6 General Relativity
Special Relativity - Only inertial frames of
reference General Relativity - Includes effects
of acceleration on what we observe

• Motivation try to include all natural phenomena
  within the framework of Sp. Relativity.
• Principle of Equivalence
• - A homogeneous gravitational field is completely
  equivalent to a uniformly accelerated ref frame.
• Or
• An observer in a closed lab cannot distinguish
  between the effects due tp gravity and that due
  to acceleration of the lab.
• Newtonian Mechanics

(inertial m)
(gravitational m)
http//www.krioma.net/articles/Bridge20Theory/Ein
stein20Rosen20Bridge.htm
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Gravity and light - If a light beam is directed
across an accelerating laboratory, its path
relative to the laboratory will be curved.
light takes 0.01s to travel 3000km - a beam of
light should fall 0.5mm near the earths surface
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Einstein Prediction in 1915 Eddington
experimentally verified in 1919
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Gravitational Lensing
NASA/Science Visuals Unlimited
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Other prediction of General Relativity

• Precession of perihelion of Mercury
• Gravitational Red Shift
• - rates of clocks and frequencies of light in
  gravitational field.

Time taken for trip is longer than for a clock at
rest clocks slow down in the presence of gravity
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Gravitational waves - Binary Pulsar Nobel prize
1993
Delay of light in a gravitational field