Heinrich Hertz
Heinrich Hertz | |
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University of Karlsruhe University of Bonn | |
Doctoral advisor | Hermann von Helmholtz |
Doctoral students | Vilhelm Bjerknes |
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Articles about |
Electromagnetism |
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Heinrich Rudolf Hertz (
Biography
Heinrich Rudolf Hertz was born in 1857 in
While studying at the
In 1886, Hertz married Elisabeth Doll, the daughter of Max Doll, a lecturer in geometry at Karlsruhe. They had two daughters: Johanna, born on 20 October 1887 and Mathilde, born on 14 January 1891, who went on to become a notable biologist. During this time Hertz conducted his landmark research into electromagnetic waves.[7]
Hertz took a position of Professor of Physics and Director of the Physics Institute in Bonn on 3 April 1889, a position he held until his death. During this time he worked on theoretical mechanics with his work published in the book Die Prinzipien der Mechanik in neuem Zusammenhange dargestellt (The Principles of Mechanics Presented in a New Form), published posthumously in 1894.[8]
Death
In 1892, Hertz was diagnosed with an infection (after a bout of severe
Hertz's wife, Elisabeth Hertz (
Scientific work
Electromagnetic waves
In 1864 Scottish mathematical physicist
During Hertz's studies in 1879 Helmholtz suggested that Hertz's doctoral dissertation be on testing Maxwell's theory. Helmholtz had also proposed the "Berlin Prize" problem that year at the
In the autumn of 1886, after Hertz received his professorship at Karlsruhe, he was experimenting with a pair of Riess spirals when he noticed that discharging a Leyden jar into one of these coils produced a spark in the other coil. With an idea on how to build an apparatus, Hertz now had a way to proceed with the "Berlin Prize" problem of 1879 on proving Maxwell's theory (although the actual prize had expired uncollected in 1882).[19][20] He used a dipole antenna consisting of two collinear one-meter wires with a spark gap between their inner ends, and zinc spheres attached to the outer ends for capacitance, as a radiator. The antenna was excited by pulses of high voltage of about 30 kilovolts applied between the two sides from a Ruhmkorff coil. He received the waves with a resonant single-loop antenna with a micrometer spark gap between the ends. This experiment produced and received what are now called radio waves in the very high frequency range.
Between 1886 and 1889 Hertz conducted a series of experiments that would prove the effects he was observing were results of Maxwell's predicted electromagnetic waves. Starting in November 1887 with his paper "On Electromagnetic Effects Produced by Electrical Disturbances in Insulators", Hertz sent a series of papers to Helmholtz at the Berlin Academy, including papers in 1888 that showed transverse
Hertz did not realize the practical importance of his radio wave experiments. He stated that,[24][25][26]
It's of no use whatsoever ... this is just an experiment that proves Maestro Maxwell was right—we just have these mysterious electromagnetic waves that we cannot see with the naked eye. But they are there.
Asked about the applications of his discoveries, Hertz replied,[24][27]
Nothing, I guess
Hertz's proof of the existence of airborne electromagnetic waves led to an explosion of experimentation with this new form of electromagnetic radiation, which was called "Hertzian waves" until around 1910 when the term "
Cathode rays
In 1892, Hertz began experimenting and demonstrated that
Photoelectric effect
Hertz helped establish the
Contact mechanics
In 1881 and 1882, Hertz published two articles
To develop his theory Hertz used his observation of elliptical Newton's rings formed upon placing a glass sphere upon a lens as the basis of assuming that the pressure exerted by the sphere follows an elliptical distribution. He used the formation of Newton's rings again while validating his theory with experiments in calculating the displacement which the sphere has into the lens. Kenneth L. Johnson, K. Kendall and A. D. Roberts (JKR) used this theory as a basis while calculating the theoretical displacement or indentation depth in the presence of adhesion in 1971.[37] Hertz's theory is recovered from their formulation if the adhesion of the materials is assumed to be zero. Similar to this theory, however using different assumptions, B. V. Derjaguin, V. M. Muller and Y. P. Toporov published another theory in 1975, which came to be known as the DMT theory in the research community, which also recovered Hertz's formulations under the assumption of zero adhesion. This DMT theory proved to be premature and needed several revisions before it came to be accepted as another material contact theory in addition to the JKR theory. Both the DMT and the JKR theories form the basis of contact mechanics upon which all transition contact models are based and used in material parameter prediction in nanoindentation and atomic force microscopy. These models are central to the field of tribology and he was named as one of the 23 "Men of Tribology" by Duncan Dowson.[38] Despite preceding his great work on electromagnetism (which he himself considered with his characteristic soberness to be trivial[24]), Hertz's research on contact mechanics has facilitated the age of nanotechnology.
Hertz also described the "Hertzian cone", a type of fracture mode in brittle solids caused by the transmission of stress waves.[39]
Meteorology
Hertz always had a deep interest in
Philosophy of science
In the introduction of his 1894 book Principles of Mechanics, Hertz discusses the different "pictures" used to represent physics in his time including the picture of
Third Reich treatment
Because Hertz's family converted from Judaism to Lutheranism two decades before his birth, his legacy ran afoul of the Nazi government in the 1930s, a regime that classified people by "race" instead of religious affiliation.[44][45]
Hertz's name was removed from streets and institutions and there was even a movement to rename the frequency unit named in his honor (hertz) after Hermann von Helmholtz instead, keeping the symbol (Hz) unchanged.[45]
His family was also persecuted for their non-Aryan status. Hertz's youngest daughter, Mathilde, lost a lectureship at Berlin University after the Nazis came to power and within a few years she, her sister, and their mother left Germany and settled in England.[46]
Legacy and honors
Heinrich Hertz's nephew,
The SI unit
In 1928 the Heinrich-Hertz Institute for Oscillation Research was founded in Berlin. Today known as the Fraunhofer Institute for Telecommunications, Heinrich Hertz Institute, HHI.
In 1969, in East Germany, a Heinrich Hertz memorial medal[49] was cast.
The IEEE Heinrich Hertz Medal, established in 1987, is "for outstanding achievements in Hertzian waves [...] presented annually to an individual for achievements which are theoretical or experimental in nature".
The Submillimeter Radio Telescope at Mt. Graham, Arizona, constructed in 1992 is named after him.
A
On his birthday in 2012, Google honored Hertz with a
Works
- Ueber die Induction in rotirenden Kugeln (in German). Berlin: Gustav Schade. 1880.
- Die Prinzipien der Mechanik in neuem Zusammenhange dargestellt (in German). Leipzig: Johann Ambrosius Barth. 1894.
- Schriften vermischten Inhalts (in German). Leipzig: Johann Ambrosius Barth. 1895.
-
Ueber die Induction in rotirenden Kugeln, 1880
-
Schriften vermischten Inhalts, 1895
See also
- Lists and histories
- Electromagnetic radiation
- Other
References
- ISBN 978-3-11-018202-6.
- ISBN 978-3-411-04067-4.
- ^ "IEC History". Iec.ch. Archived from the original on 19 May 2013.
- ^ "Biography: Heinrich Rudolf Hertz". MacTutor History of Mathematics archive. Retrieved 2 February 2013.
- ^ Buchwald 2011, p. 45
- ^ Buchwald 2011, pp. 51-65
- ^ Buchwald 2011, p. 218
- ^ Stathis Psillos, Philosophy of Science A-Z, Edinburgh University Press · 2007, page 107
- ^ Robertson, O'Connor. "Heinrich Rudolf Hertz". MacTutor. University of Saint Andrews, Scotland. Retrieved 20 October 2020.
- ^ Hamburger Friedhöfe » Ohlsdorf » Prominente. Friedhof-hamburg.de. Retrieved 22 August 2014.
- ^ Plan Ohlsdorfer Friedhof (Map of Ohlsdorf Cemetery). friedhof-hamburg.de.
- ^ IEEE Institute, Did You Know? Historical ‘Facts’ That Are Not True Archived 10 January 2014 at the Wayback Machine
- ISBN 0-911302-74-3
- ^ a b Appleyard, Rollo (October 1927). "Pioneers of Electrical Communication part 5 – Heinrich Rudolph Hertz" (PDF). Electrical Communication. 6 (2). New York: International Standard Electric Corp.: 63–77. Retrieved 19 December 2015.The two images shown are p. 66, fig. 3 and p. 70 fig. 9
- ^ O'Connor, J.J.; Robertson, E.F. (November 1997). "James Clerk Maxwell". School of Mathematical and Computational Sciences University of St Andrews. Archived from the original on 5 November 2021. Retrieved 19 June 2021.
- ^ Heinrich Hertz. nndb.com. Retrieved 22 August 2014.
- ^ ISBN 0-7923-4653-X. p. 49
- ISBN 0195171985. p. 148
- ISBN 0-7923-4653-X. p. 53
- ^ ISBN 0471205052. p. 202
- ^ "The most important Experiments – The most important Experiments and their Publication between 1886 and 1889". Fraunhofer Heinrich Hertz Institute. Retrieved 19 February 2016.
- ^ Buchwald 2011, pp. 77-91
- ^ a b c d Pierce, George Washington (1910). Principles of Wireless Telegraphy. New York: McGraw-Hill Book Co. pp. 51–55.
- ^ a b c "Heinrich Rudolph Hertz". History. Institute of Chemistry, Hebrew Univ. of Jerusalem website. 2004. Archived from the original on 25 September 2009. Retrieved 6 March 2018.
{{cite web}}
: CS1 maint: bot: original URL status unknown (link) - ISBN 9812709207. p 93.
- ISBN 0750307196.
- ISBN 1-4297-4036-1.
- ^ "The Nobel Prize in Physics 1909". Nobel Foundation. Retrieved 18 January 2019.
- ^ "Heinrich Hertz | German physicist". Encyclopedia Britannica. Retrieved 21 May 2021.
- ^ "How Radio Works". HowStuffWorks. 7 December 2000. Retrieved 14 March 2019.
- ^ Buchwald 2011, pp. 151-153
- ^ Buchwald 2011, p. 244
- S2CID 123604617.
- ^ Hertz, Heinrich (1882). "Über die Berührung fester elastischer Körper und über die Härte". Verhandlungen des Vereins zur Beförderung des Gewerbefleißes. 1882: 449–463. Retrieved 9 February 2022.
- ^ Hertz, Heinrich (1986). Miscellaneous Papers. London: Macmillan and Co, Ltd. pp. 146–183. Retrieved 13 February 2022.
- ^ Tevis D. B. Jacobs, C. M. Mate, Kevin T. Turner, Robert W Carpick, Understanding the tip-sample contact: An overview of contact mechanics at the nanoscale, November 2013
- S2CID 137730057.
- ISSN 0022-2305.
- ^ "Purdue University - Study on Hertzian cone crack"
- ISSN 1521-3889.
- doi:10.1119/1.18565.
- ^ ISBN 978-0-415-25069-6, retrieved 24 August 2023
- ^ Fielding, James Matthew (2023). The Movement of Thought: Wittgenstein on Time, Change and History. Springer International Publishing. p. 219.
- ISBN 0-684-31320-0. Vol. 6, p. 340.
- ^ a b Wolff, Stefan L. (2008-01-04) Juden wider Willen – Wie es den Nachkommen des Physikers Heinrich Hertz im NS-Wissenschaftsbetrieb erging. Jüdische Allgemeine.
- ^ MacRakies K. 1993. Surviving the Swastika: Scientific Research in Nazi Germany. New York, USA: Oxford University Press
- S2CID 121101068.
- ^ Brian Taylor, H. Gustav Mueller, Fitting and Dispensing Hearing Aids, Plural Publishing, Incorporated · 2020, page 29
- ^ Heinrich Rudolf Hertz Archived 3 June 2013 at the Wayback Machine. Highfields-arc.co.uk. Retrieved 22 August 2014.
- ^ Albanesius, Chloe (22 February 2012). "Google Doodle Honors Heinrich Hertz, Electromagnetic Wave Pioneer". PC Magazine. Retrieved 22 February 2012.
- ^ Heinrich Rudolf Hertz's 155th Birthday. Google (22 February 2012). Retrieved 22 August 2014.
Further reading
- Hertz, H.R. "Ueber sehr schnelle electrische Schwingungen", Annalen der Physik, vol. 267, no. 7, p. 421–448, May 1887
- Hertz, H.R. "Ueber einen Einfluss des ultravioletten Lichtes auf die electrische Entladung", Annalen der Physik, vol. 267, no. 8, p. 983–1000, June 1887
- Hertz, H.R. "Ueber die Einwirkung einer geradlinigen electrischen Schwingung auf eine benachbarte Strombahn", Annalen der Physik, vol. 270, no. 5, p. 155–170, March 1888
- Hertz, H.R. "Ueber die Ausbreitungsgeschwindigkeit der electrodynamischen Wirkungen", Annalen der Physik, vol. 270, no. 7, p. 551–569, May 1888
- Hertz, H. R.(1899) The Principles of Mechanics Presented in a New Form, London, Macmillan, with an introduction by Hermann von Helmholtz (English translation of Die Prinzipien der Mechanik in neuem Zusammenhange dargestellt, Leipzig, posthumously published in 1894).
———
- Appleyard, Rollo. (1930). Pioneers of Electrical Communication". London: ISBN 0-8369-0156-8
- Bodanis, David. (2006). Electric Universe: How Electricity Switched on the Modern World. New York: ISBN 0-307-33598-4
- Bryant, John H. (1988). Heinrich Hertz, the Beginning of Microwaves: Discovery of Electromagnetic Waves and Opening of the Electromagnetic Spectrum by Heinrich Hertz in the Years 1886–1892. New York: IEEE (Institute of Electrical and Electronics Engineers). ISBN 0-87942-710-8
- ISBN 9780226078915
- Jenkins, John D. "The Discovery of Radio Waves – 1888; Heinrich Rudolf Hertz (1847–1894)" (retrieved 27 Jan 2008)
- Lodge, Oliver Joseph (1897), Signaling Across Space without Wires by Electric Waves: Being a Description of the work of Hertz and his Successors, London: "The Electrician" Printing and Pub. Co.
- Maugis, Daniel. (2000). Contact, Adhesion and Rupture of Elastic Solids. New York: Springer-Verlag. ISBN 3-540-66113-1
- Naughton, Russell. "Heinrich Rudolph (alt: Rudolf) Hertz, Dr : 1857 – 1894" (retrieved 27 Jan 2008)
- Roberge, Pierre R. "Heinrich Rudolph Hertz, 1857–1894" (retrieved 27 Jan 2008)
- Susskind, Charles. (1995). Heinrich Hertz: A Short Life. San Francisco: San Francisco Press. ISBN 0-911302-74-3
External links
- Encyclopædia Britannica. Vol. 13 (11th ed.). 1911. pp. 400–401. .
- Newspaper clippings about Heinrich Hertz in the 20th Century Press Archives of the ZBW