**The Brachistochrone**

This animation is about one of the most significant problems in the history of mathematics: *The Brachistochrone Challenge*:

*If a ball is to roll down a ramp which connects two points, what must be the shape of the ramp’s curve be, such that the descent time is a minimum?*

Intuition says that it should be a straight line. That would minimize the distance, but the minimum *time* happens when the ramp curve is the one shown: a *cycloid*.

Johann Bernoulli posed the problem to the mathematicians of Europe in 1696, and ultimately, several found the solution. However, a new branch of mathematics,*Calculus of Variations*, had to be invented to deal with such problems. Today, calculus of variations is vital in Quantum Mechanics and other fields.