Predicting with constraints

Force, mass, acceleration constrained; then accumulations

Set the force acting on the hedgehog and the mass of the hedgehog, and the acceleration of the hedgehog can only have one value. Force, mass and acceleration are constrained. It's an instant connection; there is no time delay. Not first one thing, then another.

This acceleration accumulates a velocity. The velocity accumulates a displacement. So constraining the acceleration allows you to predict changes in motion.