In trigonometry, one can solve for the tangent of a curve by assuming two points on a curve become infinitely close to each other. After this line is derived, it is called the tangent line. A velocity along this line can be solved for in physics to give a vector. A velocity is determined by solving for infinity by saying that it approaches a limit, dividing 0/0. Then couldn’t one assume that they could find a vector that is on the x or y axis of the Cartesian Coordinate Plane? Someone could then take the derivative of that vector in order to solve for what vector an object could take down the center of a black hole? Why wouldn’t it be as simple as taking the derivative of the equation? It seems like it is something that would have to be done in order to program simulations of what would happen if an object fell into a black hole. This is what the presenter of this simulation claims to other scientists at the World Science Festival It would appear as though at some level the computer program would have already computed values coming really closely to what would be needed to take a limit for a vector going inside of a black hole. The programmer never released how that was accomplished.