Calculating Time Delay
In a near-static gravitational field of moderate strength (say, of stars and planets, but not one of a black hole or close binary system of neutron stars) the effect may be considered as a special case of gravitational time dilation. According to special relativity, the speed of light is constant for measurements in a local reference frame. However, this is not true for non-local paths along which a gravitational field is present. The measured elapsed time of a light signal in a gravitational field is longer than it would be without the field, and for moderate strength near-static fields the difference is directly proportional to the classical gravitational potential, precisely as given by standard gravitational time dilation formulas.
Read more about this topic: Shapiro Delay
Famous quotes containing the words calculating, time and/or delay:
“What our children have to fear is not the cars on the highways of tomorrow but our own pleasure in calculating the most elegant parameters of their deaths.”
—J.G. (James Graham)
“I take enormous pleasure every time I see something that I’ve done that cannot be wiped out. In some way ... I guess it’s a protest against mortality. But it’s been so much fun! It’s the curiosity that drives me. It’s making a difference in the world that prevents me from ever giving up.”
—Deborah Meier (b. 1931)
“Hatred and vengeance, my eternal portion,
Scarce can endure delay of execution:—
Wait, with impatient readiness, to seize my
Soul in a moment.”
—William Cowper (1731–1800)