Illustration: (Right) Piet Mondrian, “Composition with Large Red Plane, Yellow, Black, Grey and Blue” (1921), © 2009 Mondrian/Holtzman Trust c/o HCR
(Left) In the 1940s, Richard Feynman invented a graphical method for carrying out calculations in quantum electrodynamics. A typical Feynman diagram shows the electromagnetic force mediated by photons. (Center) Bern et al.  use different kinds diagrams in their calculations of supergravity that permit integration of a large number of subdiagrams. Image shows an example of one of many planar diagrams used in these kinds of calculations. (Adapted from Bern et al. .) Owing to their resemblance to the work of artist Piet Mondrian (Right), these graphical computational devices are sometimes referred to as Mondrian diagrams.