Ernst Mach of experimental physics concentrated on the interference, diffraction, polarization and refraction of light in different media under external influences. From there followed important explorations in the field of supersonic fluid mechanics. Mach and physicist-photographer Peter Salcher presented their paper on this subject in 1887; it correctly describes the sound effects observed during the supersonic motion of a projectile. They deduced and experimentally confirmed the existence of a shock wave of conical shape, with the projectile at the apex. The ratio of the speed of a fluid to the local speed of sound "v"/"v" is now called the Mach number. It
Mach-O make backwards-compatible executables, the linker flag "-mmacosx-version-min=" can be used. Some versions of NetBSD have had Mach-O support added as part of an implementation of binary compatibility, which allowed some Mac OS 10.3 binaries to be executed. For Linux, a Mach-O loader was written by Shinichiro Hamaji that can load 10.6 binaries. As a more extensive solution based on this loader, the Darling Project aims at providing a complete environment allowing OS X applications to run on Linux. For the Ruby programming language, the ruby-macho library provides an implementation of a Mach-O binary parser and editor. Mach-O Mach-O, short for