Ernst mach Memes

Left side: The Mach number - a simple ratio of speed to sound that even undergrads can calculate without crying. Right side: Mach's principle - that bizarre cosmological concept suggesting inertia exists only because of all other matter in the universe. The kind of thing that makes physicists stare at walls for hours questioning reality. Both named after Ernst Mach, who clearly enjoyed watching future generations suffer through his intellectual legacy. Thanks, Ernst.