If you twist something — say, spin a top or rotate a robot’s arm — and want it to return to its exact starting point, ...

Robert Saleh likes to refer to Football 101, 301 and 501, those imaginary "college" courses that get tougher as the numbers and years of experience go higher. This week the Jets head coach read from ...

Mathematicians thought that they understood how rotation works, but now a new proof has revealed a surprising twist that ...