From: The World In Your Head by Steven Lehar

Fig. 8.8 This print by M. C. Escher (“Circle Limit IV” © 2002 Cordon Art B. V. - Baarn - Holland. All rights reserved) demonstrates how a finite representational space can represent an infinite pattern by use of a nonlinear scale. This kind of pattern could be coded in the form of standing waves in a spherical resonator whose physical properties vary in nonlinear fashion as a function of radial distance from the center, so that the speed of wave propagation diminishes with distance from the center at a rate that matches the reduction of spatial scale from the center. If the speed of wave propagation approaches zero at the periphery, that periphery will represent an infinite distance from the center.