If a person falls as far as the event horizon of a black hole, what would happen to the person's heart rate, as perceived by a distant observer (apart from the effects caused by the person's adrenaline level)?
A) The heart rate would appear to have slowed down somewhat, but not much, because of the change of the speed of light in the gravity field.
B) The heart rate would appear to be zero; his heart would appear to have stopped.
C) The heart rate would appear to have speeded up to an incredible rate.
D) The heart rate would appear to be normal since gravity has no effect on time intervals.

Question

Quizplus · Accepted Answer

As a person falls towards the event horizon of a black hole, to a distant observer, it would appear as though the person's heart rate slows down infinitely, effectively appearing to stop. This is due to the extreme gravitational time dilation effects near the event horizon, where time appears to freeze to an external observer.

If a Person Falls as Far as the Event Horizon