Gravity is by far the weakest of nature’s four fundamental forces, and physicists have spent decades asking a deceptively simple question: why? One answer, first sketched a century ago and refined ...

Dimensions beyond the four we’re familiar with could solve a host of problems in physics and cosmology. Columnist Leah Crane ...

Dimensional tolerances are critical for making parts that will fit together in an assembly and meet the design and performance goals. Getting the tolerances wrong could easily mean parts will be too ...