With Physics in the 20th Century ($49.50), publisher Harry N. Abrams has finally done for Einstein, Bethe and Feynman what it did for Picasso, Pollock and Johns: turned their life's work into a fabulous art book. Author Curt Suplee's concise and jaunty tour of the great ideas and instruments of the past century necessarily plays second cyclotron to the glorious images, most of them made possible by perhaps the physical century's greatest legacy: the computer. At far left, 48 atoms dance on the surface of a copper crystal, as seen through a scanning tunneling microscope. Near left, Benoit B. Mandelbrot's famous fractal set. Below, a computer simulation of a piece of the universe.