[bruh-kis-tuh-krohn] 
| the curve between two points that in the shortest time by a body moving under an external force without friction; the curve of quickest descent. |
[bruh-kis-tuh-kron-ik] , bra⋅chis⋅toch⋅ro⋅nous [brey-kuh-stok-ruh-nuh
s, brak-uh-] , adjective brachistochrone
the planar curve on which a body subjected only to the force of gravity will slide (without friction) between two points in the least possible time (see ). Finding the curve was a problem first posed by Galileo. In the late 17th century the Swiss mathematician Jakob Bernoulli offered a reward for the solution of this problem. He and his younger brother Johann, along with Gottfried Wilhelm Leibniz, Isaac Newton, and others, found the curve to be a cycloid (q.v.). See also isoperimetric problem.
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