"The opposite of a correct statement is a false statement. But the opposite of a profound truth may well be another profound truth."
– Niels Bohr
Graphic: B. D. Esry & C. H. Greene/Univ. of Colorado Cold collisions. This simulation shows atoms in a two-component Bose-Einstein condensate at a temperature near 1 nK, where Bohr’s formulation of the correspondence principle fails most dramatically.