Quote:

Its just physics. If you know the initial trajectory angle and speed, and the terrain, and ignore air resistance, the point of impact can be easily determined on the back of a napkin.


Be invited to the following experiment:

Device some ideal pool billiard table without holes, just bouncing boundaries, and mount some circular reflecting or bouncing obstacle right in its center. Now shoot one billiard ball such that it hits the circularly bouncing obstacle at times. You may easily determine the trajectory of such an (ideal) billiard ball - after all, it's just basic physics. Now stop the billiard ball and shoot it again with the exact same initial conditions as the first time, up to a tiny lateral displacement of, say, one electron diameter. You may easily determine the trajectory of this second billiard ball, which at the beginning is virtuallly identical to the trajectory of the first ball. You may be surprised, though, that after some 10 bounces, say, these two billiard balls follow thoroughly different trajectories. It's just physics, 'ya know.

Martin