Complex sentence: The corresponding dynamics problem is that of a rock thrown upwards; the path the rock follows is a critical point of the action; as before, this critical point is tpically a minimum, so this is called the "principle of least action".
Split into simpler sentences: The corresponding dynamics problem is that of a rock thrown upwards; the path the rock follows is a critical point of the action. As before, this critical point is typically a minimum, so this is called the "principle of least action".