another black hole question

Factual Questions
1

Alright…an object falls into a black hole. Gravity on the object’s bottom side is stronger than the top side, thus tidal forces pull and tear apart the object in a process known as “spagettification”.

Now, when an object is accelerated close to the speed of light…like when something is being drawn into the infinitely powerful gravity well of a black hole…the object foreshortens in the direction of travel…theoretically, at c the flattening is complete:
the object becomes a completely flat 2-d plane.

So, which really happens…stretch or flatten?

2

Both. These are independent features of a BH. The problem here is of frames. In the frame of the person falling, the tides are quite real and will rip them into pasta. However, in his own frame he is not accelerating to c, so there is no foreshortening. To an outside observer, the faller is getting foreshortened.

Check out the Relativity FAQ at http://math.ucr.edu/home/baez/physics/relativity.html which has info about this. Scroll down to the Black Hole section and enjoy.

3

You should be ashamed of yourself BA.

Two things that have always confused me:

  1. At the event horizon space must be infalling at c in order for c to hold locally.

  2. As the obsever approaches the EH it must be expanding at c in order for c to hold locally.