Can math.atan2 return INF?

Marko Rauhamaa marko at pacujo.net
Thu Jun 30 02:32:30 EDT 2016


Gregory Ewing <greg.ewing at canterbury.ac.nz>:

> Marko Rauhamaa wrote:
>> By the time the event horizon hits Tim at the speed of light, Tim will
>> have received all of our Universe's signals at an ever accelerating
>> frequency and increasing power. He will have seen the End of the World
>> before leaving it.
>
> I don't think that's right. From the point of view of an infalling
> observer, nothing particularly special happens at the event horizon.
> Being able to see into the future would count as rather special, I
> would have thought.

Yeah, you have a point:

   IF you could stand still, you would see light from behind as
   blue-shifted, precisely the flip side of gravitational redshifting
   for distant observers. However, if you were traveling on a free-fall
   geodesic, you would see no blueshift from light directly behind,
   because you and it would be in the same inertial reference frame.

   <URL: http://physics.stackexchange.com/questions/26185/what-will-th
   e-universe-look-like-for-anyone-falling-into-a-black-hole>


Marko


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