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Ernst Mach (February 18, 1838 – February 19, 1916) was an Austrian physicist and philosopher and is the namesake for the Mach number and the optical illusion known as Mach bands.
t Mach was born in Chirlitz, in the Austrian empire (now Chrlice, part of Brno, Czech Republic). His father was tutor to the Brethon noble family in Zlín, eastern Moravia, having graduated from Prague University. Some sources state that Mach's birthplace was Turas/Turany (now part of Brno too), but this was where the Chirlitz registry office was situated.
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Quotations
Explanation is nothing but condensed descriptions.
Substance is a convenient word for a gap in our thoughts.
The mechanical theory of nature… is an artificial conception.
Or, most revealing: “Purely mechanical phenomena… are abstractions.”
The aim of natural science is to obtain connections among phenomena. Theories, however, are like withered leaves, which drop off after having enabled the organism of science to breathe for a time.
This absolute time Newton's idea can be measured by comparison with no motion; it has therefore neither a practical nor a scientific value; and no one is justified in saying that he knows aught about it. It is an idle metaphysical conception.
Encyclopedia
Ernst Mach (February 18, 1838 – February 19, 1916) was an Austrian physicist and philosopher and is the namesake for the Mach number and the optical illusion known as Mach bands.
Biography
Ernst Mach was born in Chirlitz, in the Austrian empire (now Chrlice, part of Brno, Czech Republic). His father was tutor to the Brethon noble family in Zlín, eastern Moravia, having graduated from Prague University. Some sources state that Mach's birthplace was Turas/Turany (now part of Brno too), but this was where the Chirlitz registry office was situated. In Turas/Turany Ernst Mach was
baptized a Roman Catholic by Peregrin Weiss.
Up to the age of 14 he was educated at home by his parents. He then joined a Gymnasium in Kremsier (now Kromeríž), where he studied for three years. In 1855 he entered the University of Vienna. There he studied physics and for one semester medical physiology, receiving his doctorate in physics in 1860 and his Habilitation the following year. His early work focused on the Doppler effect in optics and acoustics. In 1864 he took a job as Professor of Mathematics in Graz, having turned down the position of a chair in surgery at the University of Salzburg to do so, and in 1866 he was appointed as Professor of Physics. During that period Mach continued his work in psycho-physics and in sensory perception. In 1867 he took the chair of Professor of Experimental Physics at Charles-Ferdinand University, Prague, where he stayed for 28 years.
Mach's main contribution to physics was his description and photographs of spark shock waves and then ballistic shock waves. He described how passing the barrier of sound compressed air in front of bullets and shells. Using a so-called "schlierenmethode" he and his son Ludwig were able to photograph the shadows of the invisible shock waves. During the early 1890s Ludwig was able to invent an interferometer which allowed for much clearer photographs. But Mach also made many contributions to psychology and physiology including his anticipation of gestalt phenomena, his discovery of Mach bands an inhibition influenced type of visual illusion, and especially his discovery of a non-acoustic function of the inner ear which helped control human balance.
Mach is also well-known for his philosophy, which was a type of phenomenalism recognizing only sensations as real. This position was not compatible with the view that atoms and molecules were external, mind-independent things, and from about 1908 to 1911 his reluctance to acknowledge the reality of atoms was criticized by Max Planck as being incompatible with physics. Some of Mach's criticisms of Newton's position on space and time influenced Einstein, but later Einstein realized that Mach was basically opposed to Newton's philosophy and that his physical criticism was not sound. As an experimental physicist Mach tended to think that scientific theories were only provisional and had no lasting place in physics. This attitude made it hard for him to accept Einstein's special theory of relativity, especially since the second axiom seemed like an absolute of the kind Mach opposed, which was criticized in the preface to a posthumously published book on light which appeared in 1921.
In 1898 he suffered a stroke and in 1901 retired from the University of Vienna and was appointed to the upper chamber of the Austrian parliament. On leaving Vienna in 1913 he moved to his son's home in Vaterstetten, near Munich where he continued writing and corresponding until his death in 1916.
Physics
Most of his studies in the field of experimental physics were devoted to interference, diffraction, polarization and refraction of light in different media under external influences. These studies were soon followed by his important explorations in the field of supersonic velocity. Mach's paper on this subject was published in 1877 and correctly describes the sound effects observed during the supersonic motion of a projectile. Mach deduced and experimentally confirmed the existence of a shock wave which has the form of a cone with the projectile at the apex. The ratio of the speed of projectile to the speed of sound vp/vs is now called the Mach number. It plays a crucial role in aerodynamics and hydrodynamics. He also contributed to cosmology the hypothesis known as Mach's principle.
Philosophy of science
Mach developed a philosophy of science which was influential in the 19th and 20th centuries.
Mach held that scientific laws are summaries of experimental events,
constructed for the purpose of human comprehension of complex data.
Thus scientific laws have more to do with describing sensations than with reality as it exists beyond sensations.
Some quotations from Mach's writings will illustrate his philosophy.
These selections are taken from his essay The Economical Nature of Physical Inquiry, excerpted by Kockelmans (citation below).
In accordance with this philosophy, Mach opposed Ludwig Boltzmann and others who proposed an atomic theory of physics. Since atoms are too small to observe directly, and no atomic model at the time was consistent, the atomic hypothesis seemed to Mach to be unwarranted, and perhaps not sufficiently "economical".
Mach had a direct influence on the Vienna Circle philosophers and the school of logical positivism in general. Albert Einstein called him the "forerunner of [the] Theory of relativity", though Mach would later, to Einstein's disappointment, reject Einstein's theory.
Mach's positivism was also influential on many Russian Marxists, such as Alexander Bogdanov. In 1908, Lenin wrote a philosophical work Materialism and Empirio-Criticism in which he criticized the views of "Russian Machists".
Psychology
In the area of sensory perception, he is best known for an optical illusion called the Mach band.
In theoretical psychology Mach's position on mediating structures is credited with inspiring B. F. Skinner's strongly inductive position which paralleled Mach's, but in the realm of psychology
Eponyms
The lunar crater Mach is named after him.
Mach's Main Books in English
- The Science of Mechanics (1893)
- The Analysis of Sensations (1897)
- Popular Scientific Lectures (1895)
- The Principles of Physical Optics (1926)
- Knowledge and Error (1976)
- Principles of the Theory of Heat (1986)
See also
Further reading
- J. Kockelmans. Philosophy of science: the historical background. New York: The Free Press, 1968.
- John T. Blackmore, "Ernst Mach - His Life, Work, an Influence", Berkeley and Los Angeles, 1972
- John Blackmore (ed.), ."Ernst Mach - A Deeper Look", Dordrecht, 1992.
- J. Blackmore, R. Itagaki and S. Tanaka (eds.): "Ernst Mach's Vienna - 1895-1930", Dordrecht, 2001
- John T. Blackmore, Ryoichi Itagaki and Setsuko Tanaka (eds.):" Ernst Mach's Science",Tokai University Press, Kanagawa, 2006
- Erik C. Banks, Ernst Mach's World Elements, Kluwer (now Springer), Dordrecht, 203.
- John Blackmore und Klaus Hentschel (Hrsg.) "Ernst Mach als Aussenseiter", [Korrespondenz], Braumüller, 1985.
- Rudolf Haller & Friedrich Stadler (Hrsg., "Ernst Mach - Werk und Wirkung", Hoelder-Pichler-Tempsky, Wien, 1988.)
- D. Hoffmann und H. Laitko (Hrsg.), Ernst Mach -Studien und Dokumente..., Berlin, 1991.
- V. Prosser and J. Folta (eds.), "Ernst Mach and the development of Physics - Conference Papers", Prague, 1991.
- Joachim Thiele (Hrsg.), "Wissenschaftliche Kommunikation - Die Korrespondenz Ernst Machs", Kastellaun, 1978.
- Jiri Prochazka: Ernst Mach: 1838-1916. Genealogie. /Vol.I/.Brno 2OO7.
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