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Old 05-November-2009, 12:36 AM
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StupendousMan StupendousMan is offline
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Default integrated, not instantaneous

Quote:
Originally Posted by George

Points B & D are the transverse velocities and would exhibit no light velocity difference. Comparing velocities at points C and A, however, will exhibit the greatest difference. Thus, the D-B and B-D should have the greatest time variation. [This is also true with redshift/blueshift for constant c.]
You are correct as far as instantaneous velocity goes. At points B and D, the velocity of the star is transverse to the line of sight, and so there would be no change in the speed of light emitted by the star under Galilean principles.

However, if you compute the time difference between the arrival time of light emitted when the star is at point A, and when the star is point C, and when the star is at point A again, you'll see that this pair of points is the pair which shows the largest difference in light arrival times.
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