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Birth
Ernst Mach was born in Chirlitz-Turas, Moravia, Austrian Empire (modern day Brno-Chrlice, Czech Republic). Mach was home schooled until the age of 15, when he then enter a Gymnasium in Kremsier. At the age of 17, Mach became a student at the University of Vienna, studying physics, philosophy, and mathematics. 5 years later, he received his doctorates in physics, doing his thesis on "electrical charge and induction." “Ernst Mach.” Famous Scientists, www.famousscientists.org/ernst-mach/. -
Contribution to Doppler Effect
At the age of 22, Mach was successfully able to produce the Doppler effect in a laboratory with a piece of apparatus. This supported Christian Doppler's theory that the frequency of sound changes as an object approaches and passes, which was not appreciated during Doppler's life. Reichenbach, H. “Contributions of Ernst Mach to Fluid Mechanics.” Annual Review of Fluid Mechanics, vol. 15, no. 1, 1983, pp. 1–29., doi:10.1146/annurev.fl.15.010183.000245. -
Mach Bands (Optical Illusions)
In 1865, Mach described the Mach Bands illusion. Mach Bands are Illusory bands of intense lightness and darkness perceived adjacent to borders of light and dark in a visual image, caused by early image-processing in the retina and optic nerve. Banks, Erik C. “Ernst Mach and the Episode of the Monocular Depth Sensations.” Journal of the History of the Behavioral Sciences, vol. 37, no. 4, 2001, pp. 327–348., doi:10.1002/jhbs.1064. -
Non-Acoustic Function & Human Balance
In 1863, Mach began a career interested in acoustic phenomena. In the 1870's, Mach partnered with Johann Kessel in projects to describe the role of the semicircular canals and labyrinth in people's abilities to balance. In 1873 he discovered that a non-acoustic function of the inner ear actually helped control human balance. Hui, Alexandra. “Changeable Ears: Ernst Mach’s and Max Planck’s Studies of Accommodation in Hearing.” Osiris, vol. 28, no. 1, 2013, pp. 119–145., doi:10.1086/671366. -
The Mach number
Mach decided to study the effects of supersonic velocities when he noticed a change in air flow patterns as an object approached the speed of sound. Mach spent 20 years firing bullets past a swinging arm in an attempt to match and record the speed. He successfully photographed a bullet at the speed of sound which confirmed a shock wave in the form of a cone shape, known as a Mach angle. In 1929, it was suggested to term this velocity the Mach Number. -
Later life & Death
In 1897, Mach suffered from a stroke that left the right side of his body paralyzed. In 1901, he then retired from the University of Vienna and was appointed to the upper chamber of the Austrian parliament. Shortly after in 1910, his autobiography was published. In 1913, Mach moved to his son's home in Vaterstetten, where he continued writing until his death in 1916. “Ernst Mach.” Famous Scientists, www.famousscientists.org/ernst-mach/.