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Hermann von Helmholtz

"Helmholtz" redirects here. For other uses, see Helmholtz (disambiguation).

Hermann Ludwig Ferdinand von Helmholtz ForMemRS (/ˈhɛlmhoʊlts/; German: [ˈhɛʁ.man vɔn ˈhɛlmˌhɔlts]; 31 August 1821 – 8 September 1894) was a German physicist and physician who made significant contributions in several scientific fields, particularly hydrodynamic stability.[2] The Helmholtz Association, the largest German association of research institutions, is named in his honour.[3]

Hermann von Helmholtz
ForMemRS
Born(1821-08-31)31 August 1821
Potsdam, Kingdom of Prussia
Died8 September 1894(1894-09-08) (aged 73)
Charlottenburg, German Empire
EducationMedicinisch-chirurgisches Friedrich-Wilhelm-Institut (MD)
Known for
See list
Spouse
​
(m. 1861)​
Children3
RelativesAnna Augusta Von Helmholtz-Phelan (grand-niece)
Awards
Scientific career
Fields
Institutions
ThesisDe fabrica systematis nervosi evertebratorum (1842)
Doctoral advisorJohannes Peter Müller
Doctoral students
Other notable students
Signature
Helmholtz's polyphonic siren, Hunterian Museum, Glasgow

In the fields of physiology and psychology, Helmholtz is known for his mathematics concerning the eye, theories of vision, ideas on the visual perception of space, colour vision research, the sensation of tone, perceptions of sound, and empiricism in the physiology of perception. In physics, he is known for his theories on the conservation of energy and on the electrical double layer, work in electrodynamics, chemical thermodynamics, and on a mechanical foundation of thermodynamics. Although credit is shared with Julius von Mayer, James Joule, and Daniel Bernoulli—among others—for the energy conservation principles that eventually led to the first law of thermodynamics, he is credited with the first formulation of the energy conservation principle in its maximally general form.[4]

As a philosopher, he is known for his philosophy of science, ideas on the relation between the laws of perception and the laws of nature, the science of aesthetics, and ideas on the civilizing power of science. By the late nineteenth century, Helmholtz's development of a broadly Kantian methodology, including the a priori determination of the manifold of possible orientations in perceptual space, had inspired new readings of Kant[4] and contributed to the late modern neo-Kantianism movement in philosophy.[5]

Biography

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Early years

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Helmholtz was born in Potsdam, the son of the local gymnasium headmaster, Ferdinand Helmholtz, who had studied classical philology and philosophy, and who was a close friend of the publisher and philosopher Immanuel Hermann Fichte. Helmholtz's work was influenced by the philosophy of Johann Gottlieb Fichte and Immanuel Kant. He tried to trace their theories in empirical matters like physiology.

As a young man, Helmholtz was interested in natural science, but his father wanted him to study medicine. Helmholtz earned a medical doctorate at Medicinisch-chirurgisches Friedrich-Wilhelm-Institute in 1842 and served a one-year internship at the Charité hospital[6] (because there was financial support for medical students).

Trained primarily in physiology, Helmholtz wrote on many other topics, ranging from theoretical physics to the age of the Earth, and to the origin of the Solar System.

University posts

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Helmholtz's first academic position was as a teacher of anatomy at the Academy of Arts in Berlin in 1848.[7] He then moved to take a post of associate professor of physiology at the Prussian University of Königsberg, where he was appointed in 1849. In 1855 he accepted a full professorship of anatomy and physiology at the University of Bonn. He was not particularly happy in Bonn, however, and three years later he transferred to the University of Heidelberg, in Baden, where he served as professor of physiology. In 1871 he accepted his final university position, as professor of physics at the Friedrich Wilhelm University in Berlin.

Research

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Helmholtz in 1848

Mechanics

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His first important scientific achievement, an 1847 treatise on the conservation of energy, was written in the context of his medical studies and philosophical background. His work on energy conservation came about while studying muscle metabolism. He tried to demonstrate that no energy is lost in muscle movement, motivated by the implication that there were no vital forces necessary to move a muscle. This was a rejection of the speculative tradition of Naturphilosophie and vitalism which was at that time a dominant philosophical paradigm in German physiology. He was working against the argument, promoted by some vitalists, that "living force" can power a machine indefinitely.[4]

Drawing on the earlier work of Sadi Carnot, Benoît Paul Émile Clapeyron and James Prescott Joule, he postulated a relationship between mechanics, heat, light, electricity and magnetism by treating them all as manifestations of a single force, or energy in today's terminology. He published his theories in his book Über die Erhaltung der Kraft (On the Conservation of Force, 1847).[8]

In the 1850s and 60s, building on the publications of William Thomson, Helmholtz and William Rankine helped popularize the idea of the heat death of the universe.

In fluid dynamics, Helmholtz made several contributions, including Helmholtz's theorems for vortex dynamics in inviscid fluids.

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    1889 copy of Helmholtz's "Uber die Erhaltung der Kraft", no. 1
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    Title page of "Uber die Erhaltung der Kraft", no. 1
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    First page of "Uber die Erhaltung der Kraft", no. 1

Sensory physiology

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Helmholtz was a pioneer in the scientific study of human vision and audition. Inspired by psychophysics, he was interested in the relationships between measurable physical stimuli and their correspondent human perceptions. For example, the amplitude of a sound wave can be varied, causing the sound to appear louder or softer, but a linear step in sound pressure amplitude does not result in a linear step in perceived loudness. The physical sound needs to be increased exponentially in order for equal steps to seem linear, a fact that is used in current electronic devices to control volume. Helmholtz paved the way in experimental studies on the relationship between the physical energy (physics) and its appreciation (psychology), with the goal in mind to develop "psychophysical laws".

The sensory physiology of Helmholtz was the basis of the work of Wilhelm Wundt, a student of Helmholtz, who is considered one of the founders of experimental psychology. More explicitly than Helmholtz, Wundt described his research as a form of empirical philosophy and as a study of the mind as something separate. Helmholtz had, in his early repudiation of Naturphilosophie, stressed the importance of materialism, and was focusing more on the unity of "mind" and body.[9]

Ophthalmic optics

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In 1851, Helmholtz revolutionized the field of ophthalmology with the invention of the ophthalmoscope; an instrument used to examine the inside of the human eye. This made him world-famous overnight. Helmholtz's interests at that time were increasingly focused on the physiology of the senses. His main publication, titled Handbuch der Physiologischen Optik (Handbook of Physiological Optics or Treatise on Physiological Optics; English translation of the 3rd volume here), provided empirical theories on depth perception, colour vision, and motion perception, and became the fundamental reference work in his field during the second half of the nineteenth century. In the third and final volume, published in 1867, Helmholtz described the importance of unconscious inferences for perception. The Handbuch was first translated into English under the editorship of James P. C. Southall on behalf of the Optical Society of America in 1924–5. His theory of accommodation went unchallenged until the final decade of the 20th century.

Helmholtz continued to work for several decades on several editions of the handbook, frequently updating his work because of his dispute with Ewald Hering who held opposite views on spatial and colour vision. This dispute divided the discipline of physiology during the second half of the 1800s.

Nerve physiology

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In 1849, while at Königsberg, Helmholtz measured the speed at which the signal is carried along a nerve fibre. At that time most people believed that nerve signals passed along nerves immeasurably fast.[10] He used a recently dissected sciatic nerve of a frog and the calf muscle to which it attached. He used a galvanometer as a sensitive timing device, attaching a mirror to the needle to reflect a light beam across the room to a scale which gave much greater sensitivity.[10] Helmholtz reported[11][12] transmission speeds in the range of 24.6 – 38.4 meters per second.[10]

Acoustics and aesthetics

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Last photograph of von Helmholtz, taken three days before his final illness
 
The Helmholtz resonator (i) and instrumentation

In 1863, Helmholtz published Sensations of Tone, once again demonstrating his interest in the physics of perception. This book influenced musicologists into the twentieth century. Helmholtz invented the Helmholtz resonator to identify the various frequencies or pitches of the pure sine wave components of complex sounds containing multiple tones.[13]

Helmholtz showed that different combinations of resonators could mimic vowel sounds: Alexander Graham Bell in particular was interested in this but, not being able to read German, misconstrued Helmholtz's diagrams as meaning that Helmholtz had transmitted multiple frequencies by wire—which would allow multiplexing of telegraph signals—whereas, in reality, electrical power was used only to keep the resonators in motion. Bell failed to reproduce what he thought Helmholtz had done but later said that, had he been able to read German, he would not have gone on to invent the telephone on the harmonic telegraph principle.[14][15][16][17]

 
Helmholtz in 1881, portrait by Ludwig Knaus

The translation by Alexander J. Ellis was first published in 1875 (the first English edition was from the 1870 third German edition; Ellis's second English edition from the 1877 fourth German edition was published in 1885; the 1895 and 1912 third and fourth English editions were reprints of the second).[18]

Electromagnetism

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Helmholtz studied the phenomena of electrical oscillations from 1869 to 1871, and in a lecture delivered to the Naturhistorisch-medizinischen Vereins zu Heidelberg (Natural History and Medical Association of Heidelberg) on 30 April 1869, titled On Electrical Oscillations he indicated that the perceptible damped electrical oscillations in a coil joined up with a Leyden jar were about 1/50th of a second in duration.[19]

In 1871, Helmholtz moved from Heidelberg to Berlin to become a professor of physics. He became interested in electromagnetism, and the Helmholtz equation is named for him. Although he did not make major contributions to this field, his student Heinrich Rudolf Hertz became famous as the first to demonstrate electromagnetic radiation. Oliver Heaviside criticised Helmholtz's electromagnetic theory because it allowed the existence of longitudinal waves. Based on work on Maxwell's equations, Heaviside pronounced that longitudinal waves could not exist in a vacuum or a homogeneous medium. Heaviside did not note, however, that longitudinal electromagnetic waves can exist at a boundary or in an enclosed space.[20]

Philosophy

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Helmholtz scientific work in physiology and mechanics occasioned much that he is known for in philosophy of science, including ideas on the relation between the laws of perception and the laws of nature and his rejection of the exclusive use of Euclidean geometry.[21]

His philosophy of science wavered between some version of empiricism and transcendentalism.[22] Despite the speculative associations of the latter, his philosophy of science is thoroughly indebted to his use of mathematical physics to supplant vitalism and articulate the general conservation of energy principle.[4]

His rejection of Euclidean geometry as the only possible science of space is central to understanding his appropriation of Kant's philosophy of space, which ostensibly requires Euclidean geometry to be that exclusive a priori science of physical space. Helmholtz introduced a new conception of the a priori in space: that of the determination of the manifold of possible orientations in perceptual space. These developments inspired new readings of Kant[4] and contributed to the rise of late modern neo-Kantianism movement in philosophy.

Students and associates

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Other students and research associates of Helmholtz at Berlin included Max Planck, Heinrich Kayser, Eugen Goldstein, Wilhelm Wien, Arthur König, Henry Augustus Rowland, Albert A. Michelson, Wilhelm Wundt, Fernando Sanford and Michael I. Pupin. Leo Koenigsberger, who was his colleague from 1869 to 1871 in Heidelberg, wrote the definitive biography of him in 1902.

Honours and legacy

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Helmholtz's statue in front of Humboldt University in Berlin
 
 
 
Decree awarding Helmholtz (listed in first page) the French Legion of Honour

Works

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  • Über die Erhaltung der Kraft (in German). Leipzig: Wilhelm Engelmann. 1889.
  • Vorlesungen über die elektromagnetische Theorie des Lichts (in German). Leipzig: Johann Ambrosius Barth. 1897.
  • Vorlesungen über die mathematischen Principien der Akustik (in German). Leipzig: Johann Ambrosius Barth. 1898.
  • Vorlesungen über die Dynamik discreter Massenpunkte (in German). Leipzig: Johann Ambrosius Barth. 1898.
  • Dynamik continuirlich verbreiteter Massen (in German). Leipzig: Johann Ambrosius Barth. 1902.
  • Vorlesungen über die Theorie der Wärme (in German). Leipzig: Johann Ambrosius Barth. 1903.
  • Vorlesungen über Theoretische Physik (in German). Leipzig: Johann Ambrosius Barth. 1903.

Translated works

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See also

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References

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Citations

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  1. ^ David Cahan (1993). Hermann Von Helmholtz and the Foundations of Nineteenth-Century Science. University of California Press. p. 198. ISBN 978-0-520-08334-9.
  2. ^ Bobba, Kumar Manoj (1 January 2004). Robust flow stability: Theory, computations and experiments in near-wall turbulence (Thesis). Bibcode:2004PhDT.......158B.
  3. ^ a b "The polymath with a sense of practice". Helmholtz-Gemeinschaft Deutscher Forschungszentren. Retrieved 4 October 2024.
  4. ^ a b c d e Patton, Lydia. "Hermann von Helmholtz." (2008), Stanford Encyclopedia of Philosophy.
  5. ^ Heis, Jeremy (2018). "Neo-Kantianism". Stanford Encyclopedia of Philosophy. Retrieved 6 October 2024. This movement drew inspiration from a diverse cast of philosophers—principally, Kuno Fischer (Fischer 1860), Hermann von Helmholtz (Helmholtz 1867, 1878), Friedrich Lange (Lange 1866), Otto Liebmann (Liebmann 1865), and Eduard Zeller (Zeller 1862))—who in the middle of the nineteenth century were calling for a return to Kant's philosophy as an alternative to both speculative metaphysics and materialism (Beiser 2014b).
  6. ^ R. S. Turner, In the Eye's Mind: Vision and the Helmholtz-Hering Controversy, Princeton University Press, 2014, p. 36.
  7. ^ Biographical Index of Former Fellows of the Royal Society of Edinburgh 1783–2002 (PDF). The Royal Society of Edinburgh. July 2006. ISBN 0-902198-84-X. Archived from the original (PDF) on 24 January 2013. Retrieved 21 October 2016.
  8. ^ English translation published in Scientific memoirs, selected from the transactions of foreign academies of science, and from foreign journals: Natural philosophy (1853), p. 114; trans. by John Tyndall. Google Books, HathiTrust
  9. ^ Peter J. Bowler and Iwan Rhys Morus (2005). Making Modern Science: A Historical Survey. University of Chicago Press. p. 177. ISBN 978-0-226-06861-9.
  10. ^ a b c Glynn, Ian (2010). Elegance in Science. Oxford: Oxford University Press. pp. 147–150. ISBN 978-0-19-957862-7.
  11. ^ Helmholtz, Hermann von (1850).Vorläufiger Bericht über die Fortpflanzungs-Geschwindigkeit der Nervenreizung. In: Archiv für Anatomie, Physiologie und wissenschaftliche Medicin. Veit & Comp., pp. 71–73. MPIWG Berlin
  12. ^ Helmholtz, Hermann von (1850). Messungen über den zeitlichen Verlauf der Zuckung animalischer Muskeln und die Fortpflanzungsgeschwindigkeit der Reizung in den Nerven. In: Archiv für Anatomie, Physiologie und wissenschaftliche Medicin. Veit & Comp., pp. 276–364. MPIWG Berlin
  13. ^ von Helmholtz, Hermann (1885). On the sensations of tone as a physiological basis for the theory of music. Translated by Ellis, Alexander J. (Second English ed.). London: Longmans, Green, and Co. p. 44. Retrieved 12 October 2010.
  14. ^ "PBS, American Experience: The Telephone – More About Bell". PBS.
  15. ^ MacKenzie 2003, p. 41.
  16. ^ Groundwater 2005, p. 31.
  17. ^ Shulman 2008, pp. 46–48.
  18. ^ Hermann L. F. Helmholtz, M.D. (1912). On the Sensations of Tone as a Physiological Basis for the Theory of Music (Fourth ed.). Longmans, Green, and Co. ISBN 9781419178931.
  19. ^ Koenigsberger, Leo (28 March 2018). Hermann von Helmholtz. Clarendon press. ISBN 978-0-486-21517-4. Retrieved 28 March 2018 – via Google Books.
  20. ^ John D. Jackson, Classical Electrodynamics, ISBN 0-471-30932-X.
  21. ^ Helmholtz, Hermann von (1977). "On the origin and significance of the axioms of geometry". Boston Studies in the Philosophy of Science. 37: 1–38. Retrieved 13 October 2024.
  22. ^ De Kock, Liesbet (2018). "Historicizing Hermann von Helmholtz's Psychology of Differentiation". Journal for the History of Analytical Philosophy. 6 (3). doi:10.15173/jhap.v6i3.3432. hdl:1854/LU-8552480. S2CID 187618324. Retrieved 1 January 2022. Hermann von Helmholtz's peculiar wavering between empiricism and transcendentalism in his philosophy of science in general, and in his theory of perception in particular, is a much debated and well-documented topic in the history and philosophy of science.
  23. ^ "APS Member History". search.amphilsoc.org. Retrieved 3 May 2021.
  24. ^ "Honorary Fellows of the Royal College of Surgeons (RCSI) since 1784". Ireland Genealogy Project. 2013. Archived from the original on 3 February 2018. Retrieved 4 August 2016.
  25. ^ "Honorary Members and Fellows". The Institution of Engineers and Shipbuilders in Scotland.
  26. ^ "History of the name in the About section of Helmholtz Association website". Archived from the original on 14 April 2012. Retrieved 30 April 2012.
  27. ^ "11573 Helmholtz (1993 SK3)". Minor Planet Center. Retrieved 2 February 2018.
  28. ^ "Lunar crater Helmholtz". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
  29. ^ "Martian crater Helmholtz". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
  30. ^ "Helmholtzstraße". berlin.de. 21 September 2014. Retrieved 18 July 2018.

Sources

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  • Cahan, David Helmholtz: A Life in Science. University of Chicago Press, 2018. ISBN 978-0-226-48114-2.
  • Cohen, Robert, and Wartofsky, Marx, eds. and trans. Reidel. Helmholtz: Epistemological Writings, 1977.
  • Ewald, William B., ed. From Kant to Hilbert: A Source Book in the Foundations of Mathematics, 2 vols. Oxford Uni. Press, 1996.
    • 1876. "The origin and meaning of geometrical axioms", 663–88.
    • 1878. "The facts in perception", 698–726.
    • 1887. "Numbering and measuring from an epistemological viewpoint", 727–52.
  • Groundwater, Jennifer. Alexander Graham Bell: The Spirit of Invention. Calgary: Altitude Publishing, 2005. ISBN 1-55439-006-0.
  • Jackson, Myles W. Harmonious Triads: Physicists, Musicians, and Instrument Makers in Nineteenth-Century Germany (MIT Press, 2006).
  • Kahl, Russell, ed. Wesleyan. Selected Writings of Hermann von Helmholtz, Uni. Press., 1971.
  • Koenigsberger, Leo. Hermann von Helmholtz, translated by Frances A. Welby (Dover, 1965)
  • MacKenzie, Catherine. Alexander Graham Bell. Whitefish, Montana: Kessinger Publishing, 2003. ISBN 978-0-7661-4385-2. Retrieved 29 July 2009.
  • Shulman, Seth. The Telephone Gambit: Chasing Alexander Bell's Secret. New York: Norton & Company, 2008. ISBN 978-0-393-06206-9.

Further reading

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