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Old 23-07-2016, 05:21 PM
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sjastro
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Using the on line integral calculator, the solution to the equation http://members.iinet.net.au/~sjastro...s/freefall.gif reveals the coordinate time for an object dropping from 25 to 5 km for the third observer is 1.97 X 10^9 years.
Comparing this to my own calculation which required me to butcher the equation using linear approximations in order to integrate it, I obtained a value of 2.02 X 10^10 years.

Since computers do a far better job than humans when it come to brute force calculations, I'll accept the computer result as more accurate.

Using the computer result the proper time for the observer 10000km away from the singularity is 1.94 X 10^9 years and the observer 100 km away is
1.63 X 10^9 years.

This indicates the gravitational time dilation occurring.
If the calculation was for freefall from 25 km to the event horizon at 2.95 km, the coordinate time would be infinite.
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