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Description

Frontiers/Controversies in Astrophysics (ASTR 160)
Class begins with clarification of equations from the previous lecture. Four post-Newtonian gravitational effects are introduced and discussed in detail. The first of these is the so-called Perihelion Precession, which occurs when the major axis of a planet's elliptical orbit precesses within its orbital plane, in response to changing gravitational forces exerted by other planets. Secondly, deflection of light is described as the curving of light as it passes near a large mass. Gravitational redshift is explained as a frequency effect that occurs as light moves away from a massive body such as a star or black hole. Finally, the existence and effects of gravitational waves are discussed. The lecture closes with a brief history of the 1919 eclipse expedition that made Einstein famous.
00:00 - Chapter 1. Defining Black Holes in Terms of the Schwarzschild Radius
15:44 - Chapter 2. Perihelions and Deflection of Light
22:44 - Chapter 3. Hunting Eclipses
31:31 - Chapter 4. Gravitational Redshift
45:14 - Chapter 5. Gravitational Waves
Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses
This course was recorded in Spring 2007.

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