Ernst Mach

Infobox Philosopher
region = Western Philosophy
era = 20th-century philosophy
color = lightsteelblue

---

image_size = 200px
image_caption = Ernst Mach
name = Ernst Mach
birth = February 18, 1838
Brno, Austrian Empire
death = Death date and age|1916|2|19|1838|2|19
Munich, German Empire
school_tradition = Analytic philosophy, Philosophy of Science
main_interests = Epistemology, Logic, Philosophy of Science, Philosophy of mathematics
notable_ideas = Mach band
influences = Newton, Hume, Leibniz, Kant
influenced = Vienna Circle, Albert Einstein, Alexander Bogdanov, Rudolf Carnap, Bertrand Russell


box_width = 300px

Ernst Mach (pronounced|max) (February 18, 1838 – February 19, 1916) was an Austrian physicist and philosopher and is the namesake for the "Mach number" (also known as Mach speed) 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/Tuřany (now part of Brno too), but this was where the Chirlitz registry office was situated. In Turas/Tuřany Ernst Mach had beenbaptized a Roman Catholic and by cooperator Peregrin Weiss.

Up to the age of 14 he was educated at home by his parents. He then joined a Gymnasium in Kremsier (now Kroměříž), 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, 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 barrior of sound compressed air in front of bullets and shells. Using a so-called "schlierenmthod" he and his son Ludwig were able to photograph the shadows of the invisible shock waves. During the early 1890's 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.Infobox Scientist
box_width = 300px
name = Ernst Mach


image_size = 200px
caption = Ernst Mach (1838-1916)
birth_date = February 18, 1838
birth_place = Brno, Austrian Empire
death_date = Death date and age|1916|2|19|1838|2|19
death_place = Munich, German Empire
residence = German Empire, Austrian Empire, Czechoslovakia
citizenship =
nationality = Austrian
ethnicity =
fields = Physicist
workplaces = University of Graz
Charles-Ferdinand University
alma_mater = University of Vienna
doctoral_advisor = Andreas von Ettingshausen
academic_advisors =
doctoral_students = Heinrich Gomperz
notable_students = Andrija Mohorovičić
known_for = Mach number
Mach's principle
Shock waves
Mach waves
Mach reflection effect
author_abbrev_bot =
author_abbrev_zoo =
influences =
influenced = Nikola Tesla
Wolfgang Pauli
awards =
religion = Catholic; positivist


footnotes = He was the godfather of Wolfgang Pauli. The Mach-Zehnder interferometer is named after his son Ludwig Mach, who was also a physicist. Marilyn vos Savant, the 1989 Guinness Book of Records person with the highest world IQ, is a descendant of Mach.

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 "v_p"/"v_s" 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).

cquote|The goal which it [physical science] has set itself is the "simplest" and "most economical" abstract expression of facts.

When the human mind, with its limited powers, attempts to mirror in itself the rich life of the world, of which it itself is only a small part, and which it can never hope to exhaust, it has every reason for proceeding economically.

In reality, the law always contains less than the fact itself, because it does not reproduce the fact as a whole but only in that aspect of it which is important for us, the rest being intentionally or from necessity omitted.cquote|In mentally separating a body from the changeable environment in which it moves, what we really do is to extricate a group of sensations on which our thoughts are fastened and which is of relatively greater stability than the others, from the stream of all our sensations.

Suppose we were to attribute to nature the property of producing like effects in like circumstances; just these like circumstances we should not know how to find. Nature exists once only. Our schematic mental imitation alone produces like events.

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 [Mecca Chiesa: Radical Behaviorism: the philosophy and the science.]

Eponyms

The Mach (crater) 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)

Notes

References

* J. Kockelmans. "Philosophy of science: the historical background". New York: The Free Press, 1968.
* M. Chiesa. "Radical Behaviorism: the philosophy and the science".2005.
* 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.

External links

* [http://academic.udayton.edu/gregelvers/hop/?m=3&a=77&key=53 Various Ernst Mach links] , compiled by Greg C Elvers
* [http://www.archive.org/search.php?query=creator%3A(Ernst%20Mach) Works in german and english] , in the Internet Archive
*sep entry|ernst-mach|Ernst Mach|Paul Pojman
* [http://vlp.mpiwg-berlin.mpg.de/people/data?id=per313 Short biography and bibliography] in the Virtual Laboratory of the Max Planck Institute for the History of Science
* [http://www.marxists.org/archive/lenin/works/1908/mec/ Vladimir Lenin: Materialism and Empirio-Criticism]
* [http://genealogy.math.ndsu.nodak.edu/id.php?id=113010 Mach's math genealogy]

Persondata
NAME=Mach, Ernst
ALTERNATIVE NAMES=Austrian physicist and philosopher
SHORT DESCRIPTION=
DATE OF BIRTH=February 18, 1838
PLACE OF BIRTH=Chrlice (now part of Brno), Czech Republic
DATE OF DEATH=February 19, 1916
PLACE OF DEATH=Haar, Germany