Hermann von Helmholtz

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Hermann von Helmholtz
M.D.
, 1842)
Known for
Spouse
Other notable students
Helmholtz's polyphonic siren, Hunterian Museum, Glasgow

Hermann Ludwig Ferdinand von Helmholtz

research institutions, is named in his honour.[3]

In the fields of

laws of nature, the science of aesthetics
, and ideas on the civilizing power of science.

Biography

Early years

Helmholtz was born in

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[4]
(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

Helmholtz's first academic position was as a teacher of anatomy at the Academy of Arts in Berlin in 1848.

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

Helmholtz in 1848

Mechanics

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 which was at that time a dominant philosophical paradigm in German physiology.

Drawing on the earlier work of

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).[6]

In the 1850s and 60s, building on the publications of

William Thomson, Helmholtz and William Rankine popularized 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.

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

Sensory physiology

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.[7]

Ophthalmic optics

In 1851, Helmholtz revolutionized the field of

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

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.[8] 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.[8] Helmholtz reported[9][10] transmission speeds in the range of 24.6 – 38.4 meters per second.[8]

Acoustics and aesthetics

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.[11]

Helmholtz showed that different combinations of resonators could mimic

harmonic telegraph principle.[12][13][14][15]

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).[16]

Electromagnetism

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.[17]

In 1871, Helmholtz moved from Heidelberg to Berlin to become a professor of physics. He became interested in

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.[18]

Philosophy

Helmholtz wavered between empiricism and transcendentalism in his philosophy of science.[19]

Quotation

Whoever, in the pursuit of science, seeks after immediate practical utility may rest assured that he seeks in vain. — Academic Discourse (Heidelberg 1862)[20]

Students and associates

Other students and research associates of Helmholtz at Berlin included

Leo Koenigsberger
, who was his colleague from 1869 to 1871 in Heidelberg, wrote the definitive biography of him in 1902.

Honours and legacy

Helmholtz's statue in front of Humboldt University in Berlin
French Legion of Honour

Works

  • 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.

Translated works

See also

References

Notes

  1. ^ German pronunciation: [ˈhɛʁ.man vɔn ˈhɛlmˌhɔlts]

Citations

  1. .
  2. .
  3. ^ ]
  4. ^ R. S. Turner, In the Eye's Mind: Vision and the Helmholtz-Hering Controversy, Princeton University Press, 2014, p. 36.
  5. ISBN 0-902198-84-X. Archived from the original
    (PDF) on 24 January 2013. Retrieved 21 October 2016.
  6. ^ 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
  7. .
  8. ^ .
  9. ^ Vorläufiger Bericht über die Fortpflanzungs-Geschwindigkeit der Nervenreizung. In: Archiv für Anatomie, Physiologie und wissenschaftliche Medicin. Jg. 1850, Veit & Comp., Berlin 1850, S. 71–73. MPIWG Berlin
  10. ^ 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. Jg. 1850, Veit & Comp., Berlin 1850, S. 276–364. MPIWG Berlin
  11. ^ 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.
  12. ^ "PBS, American Experience: The Telephone – More About Bell". PBS.
  13. ^ MacKenzie 2003, p. 41.
  14. ^ Groundwater 2005, p. 31.
  15. ^ Shulman 2008, pp. 46–48.
  16. .
  17. . Retrieved 28 March 2018 – via Google Books.
  18. .
  19. . 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.
  20. ^ "Science". Moses King. 28 March 2018. Retrieved 28 March 2018 – via Google Books.
  21. ^ "APS Member History". search.amphilsoc.org. Retrieved 3 May 2021.
  22. ^ "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.
  23. ^ "Honorary Members and Fellows". The Institution of Engineers and Shipbuilders in Scotland.
  24. ^ "History of the name in the About section of Helmholtz Association website". Archived from the original on 14 April 2012. Retrieved 30 April 2012.
  25. ^ "11573 Helmholtz (1993 SK3)". Minor Planet Center. Retrieved 2 February 2018.
  26. ^ "Lunar crater Helmholtz". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
  27. ^ "Martian crater Helmholtz". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
  28. ^ "Helmholtzstraße". berlin.de. 21 September 2014. Retrieved 18 July 2018.

Sources

Further reading

External links