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Hendrik Lorentz

 
Britannica Concise Encyclopedia: Hendrik Antoon Lorentz
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(born July 18, 1853, Arnhem, Neth. — died Feb. 4, 1928, Haarlem) Dutch physicist. He taught at the University of Leiden (1878 – 1912) and later directed Haarlem's Teyler Institute. In 1875 he refined James Clerk Maxwell's theory of electromagnetic radiation so that it explained the reflection and refraction of light. Aiming to devise a single theory to explain the relationship of electricity, magnetism, and light, he later suggested that atoms might consist of charged particles that oscillate and produce light. In 1896 his student Pieter Zeeman (1865 – 1943) demonstrated this phenomenon (see Zeeman effect), and in 1902 the two men were awarded the second Nobel Prize for Physics. In 1904 Lorentz developed the Lorentz transformations (including the so-called Fitzgerald-Lorentz contraction), mathematical formulas that relate space and time measurements of one observer to those of a second observer moving relative to the first. These formed the basis of Albert Einstein's special theory of relativity.

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Scientist: Hendrik Antoon Lorentz
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Dutch theoretical physicist (1853–1928)

Lorentz, who was born at Arnhem in the Netherlands, studied at the University of Leiden and received his doctorate in 1875. In 1877, aged only 24, he became professor of theoretical physics at Leiden. This was the Netherlands' first chair in the newly independent field of theoretical physics, and one of the first in Europe, and Lorentz did a great deal in shaping and developing the field. On his retirement in 1912 he was appointed director of the Teyler Laboratory in Haarlem, a museum of science and art with a laboratory where he could continue his research. He still retained contact with the world of advanced physics, giving every week at Leiden his famous ‘Monday morning lectures’ on current scientific problems.

Lorentz had wide-ranging interests in physics and mathematics, his linguistic abilities allowing him to follow the scientific trends in Europe. His major work, however, was spent in the development of the electromagnetic theory of James Clerk Maxwell. He brought this to a point where a need for a radical change in the foundations of physics became noticeable and thus provided the inspiration for Einstein's theory of relativity.

Lorentz's early work on this highly complex and confused subject followed from the writings of Hermann von Helmholtz and began in his doctoral thesis. Lorentz refined Maxwell's theory so that for the first time various effects including the reflection and refraction (bending) of light could be fully explained. In a series of articles published between 1892 and 1904 Lorentz put forward his ‘electron theory’: he proposed that the atoms and molecules of matter contained small rigid bodies that carried either a positive or negative charge. By 1899 he was referring to these charged particles as ‘electrons’. It was through the effects of these electrons that many phenomena in science were explained. Lorentz believed that matter and the wave-bearing medium known as the ‘ether’ were distinct entities and that the interaction between them was mediated by electrons. He saw that the interaction of light waves and matter resulted from the presence of electrons in matter and that if set into vibration these charged particles would produce light waves, as predicted by Maxwell's equations.

In 1895 he described the force, now known as the Lorentz force, on charged particles of matter in an electromagnetic field. In 1900 he identified the negatively charged particles that had been found to constitute cathode rays as the negative electrons of his theory. He also used the theory to explain the effect discovered by Pieter Zeeman in 1896 whereby the spectral lines of sodium atoms were split by the action of a magnetic field. Lorentz and Zeeman shared the 1902 Nobel Prize for physics for their investigations of the influence of magnetic fields on radiation. However, other phenomena, such as the photoelectric effect, could not be explained and, in fact, were inconsistent with Lorentz's theory; it was these anomalies that inspired the development of the quantum theory.

The other work for which Lorentz is famous is his suggested method of resolving the problems raised by the experiments in the 1880s of Albert Michelson and Edward Morley on the motion of the Earth through the ether. Lorentz showed that if it were assumed that moving bodies contracted in the direction of motion, then the observed effects would follow. This solution was derived independently by George Fitzgerald and came to be known as the Lorentz–Fitzgerald contraction. Lorentz extended his idea, putting it on a firmer mathematical footing, and in 1904 published in final form what became known as the Lorentz transformations. These transformations of the space and time coordinates of an event in one frame of reference to those in another frame again figured largely in Einstein's theory of special relativity (1905), in which Einstein could be said to have reinterpreted Lorentz's ideas.

Lorentz devoted much time to education and the teaching of science and medicine. In later life he was very active in international science conferences, acting as president of the first Solvay Congress for physics in Brussels and continuing as president until his death. He also played a major role in restoring international scientific relations after World War I.

Biography: Hendrik Antoon Lorentz
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The work of the Dutch physicist Hendrik Antoon Lorentz (1853-1928) on electromagnetic theory led to notions equivalent to some basic postulates of the special theory of relativity.

Hendrik Antoon Lorentz, the son of Gerrit Frederik Lorentz and his wife, Geertruida van Ginkel, was born on July 18, 1853, in Aarnhem. At the age of 9 he mastered the use of a table of logarithms. In high school he excelled in the sciences, as well as in history and languages. In 1870 he passed the examinations to qualify for the University of Leiden. By the end of the next year he had become a doctoral candidate.

During the next 2 years Lorentz taught high school physics and mathematics in Aarnhem. In June 1873 he returned to Leiden and received his doctoral degree; his dissertation revealed at one stroke his extraordinary grasp of what constituted at that time the most advanced and most portentous part of theoretical physics, J. C. Maxwell's electromagnetic theory. Lorentz was not only among the relatively few on the Continent who at that time were thoroughly familiar with Maxwell's theory, but his dissertation carried some of Maxwell's ideas considerably further.

By a fortunate coincidence, Dutch university education was expanded in 1877. At the University of Leiden a new chair in physics was set up for theoretical physics with the 24-year-old Lorentz as its first occupant. The next 20 years in Lorentz's life were a time of quiet, almost isolated study. He kept abreast of the latest publications in physics without, however, trying to make personal contacts with physicists abroad. When one day he was told about a foreign-looking man wandering about on Leiden's main street, his spontaneous reaction was: "I hope he will not turn out to be a physicist." He did not in fact make his first international contact until 1897. By then he had become the father of two daughters and a son, following his marriage in 1881 to Aletta Kaiser, the niece of his physics professor at Leiden, P. Kaiser.

After his appearance at the Congress of German Scientists and Physicians in Düsseldorf in 1897, Lorentz became a central figure of international gatherings of physicists. This was due only in part to the charm of his personality and to his ability to speak in a highly literary style in German, English, and French. The 20 years spent in the privacy of his study where, as his children put it, he walked up and down like a polar bear, had been rich in creative results. First came his highly successful textbooks in calculus and physics, the latter of which went through nine editions. Far more important was the gradual development of his electromagnetic theory, in which electromagnetism was based strictly on the existence of electrons that acted on each other through a stationary ether. His assumptions led directly to the interrelation between the frequency of the field and the value of the refractive index.

These researches led Lorentz to the question of electrical and optical phenomena in moving bodies, a crucial issue in electromagnetic theory. As is well known, the uniform motion of bodies leaves those phenomena unchanged. In 1895 Lorentz put forward the now famous transformation equations that explain this situation, or rather leave the fundamental equations of electromagnetism in the same form in all reference systems moving with uniform velocity with respect to one another. In 1903 Lorentz derived the principle that electromagnetic and optical phenomena are independent of the velocity of the system in which they take place, as long as the velocity is smaller than the velocity of light. The principle is known as Lorentz's principle of correlation, and its content is equivalent to that of the special theory of relativity spelled out by Albert Einstein with more incisive generality in 1905.

The most spectacular success of Lorentz's electromagnetic theory was not its anticipation of some of Einstein's great insights, but rather the explanation of the splitting of spectral lines in strong magnetic fields, first observed by Pieter Zeeman in 1896. The discovery and the explanation made Zeeman and Lorentz the joint recipients in 1902 of the Nobel Prize for physics. Lorentz's electron theory received a full-fledged treatment in 1906 in his lectures at Columbia University, published under the title The Theory of Electrons. This first visit to the United States was followed by three more after World War I, to the California Institute of Technology and to Mt. Wilson Observatory.

After the war Lorentz was president of the famous Solvay Conferences for physics, a telling evidence of his stature in a generation that produced a galaxy of geniuses in physics. In his own country he served as director of the very complex studies preliminary to the closing of the Zuiderzee. Although in 1912 Lorentz became curator of the laboratory of the Teyler Stichting (Institute) in Haarlem, he continued at Leiden his Monday morning lectures, which were often attended by leading physicists from abroad. He died after a short illness on Feb. 4, 1928.

Further Reading

Excellent insights into personal, scientific, and civic aspects of Lorentz's life are given in the collection of essays edited by his daughter, Geertruida Luberta De Haas-Lorentz, H. A. Lorentz: Impressions on His Life and Work (trans. 1957). For an authoritative discussion of Lorentz's role in the development of modern physics consult E. T. Whittaker, A History of the Theories of Aether and Electricity (1910; rev. ed., 2 vols., 1951-1953).

 
Columbia Encyclopedia: Hendrik Antoon Lorentz
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Lorentz, Hendrik Antoon (hĕn'drək än'tōn lō'rĕnts), 1853-1928, Dutch physicist, a pioneer in formulating the relations between electricity, magnetism, and light. He was one of the first to postulate the existence of electrons. On this he based his explanation of the Zeeman effect (a change in spectrum lines in a magnetic field), for which he shared with Pieter Zeeman the 1902 Nobel Prize in Physics. He extended the hypothesis of G. F. Fitzgerald, an Irish physicist, that the length of a body contracts as its speed increases (see Lorentz contraction), and he formulated the Lorentz transformation, by which space and time coordinates of one moving system can be correlated with the known space and time coordinates of any other system. This work influenced, and was confirmed by, Einstein's special theory of relativity. Lorentz also discovered (1880), simultaneously with L. V. Lorenz of the Univ. of Copenhagen, the relations (known as Lorentz-Lorenz relations) between the refraction of light and the density of a translucent body. He was professor (1878-1912) at the Univ. of Leiden and director from 1912 of the Teyler laboratory, Haarlem. His works in English include The Theory of Electrons (1909) and Problems of Modern Physics (1927).

Bibliography

See his collected papers (9 vol., 1934-39); study ed. by G. L. de Haas-Lorentz (tr. 1957).

Wikipedia: Hendrik Lorentz
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Not to be confused with Ludvig Lorenz or Edward Norton Lorenz.
Hendrik Antoon Lorentz

Born 18 July 1853(1853-07-18)
Arnhem, Netherlands
Died 4 February 1928 (aged 74)
Haarlem, Netherlands
Nationality Netherlands
Fields Physics
Alma mater University of Leiden
Doctoral advisor Pieter Rijke
Doctoral students Geertruida L. de Haas-Lorentz
Adriaan Fokker
Leonard Ornstein
Known for Theory of EM radiation
Lorentz force
Notable awards Nobel Prize for Physics (1902)

Hendrik Antoon Lorentz (18 July 1853 – 4 February 1928) was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect. He also derived the transformation equations subsequently used by Albert Einstein to describe space and time.

Contents

Biography

Early life

Hendrik Lorentz was born in Arnhem, Gelderland (The Netherlands), the son of Gerrit Frederik Lorentz (1822 – 1893), a well-off nurseryman, and Geertruida van Ginkel (1826 – 1861). In 1862, after his mother's death, his father married Luberta Hupkes. From 1866-1869 he attended the newly established high school in Arnhem, and in 1870 he passed the exams in classical languages which were then required for admission to University.
Lorentz studied physics and mathematics at the University of Leiden, where he was strongly influenced by the teaching of astronomy professor Frederik Kaiser; it was his influence that led him to become a physicist. After earning a bachelor's degree, he returned to Arnhem in 1872 to teach high school classes in mathematics, but he continued his studies in Leiden next to his teaching position. In 1875 Lorentz earned a doctoral degree under Pieter Rijke on a thesis entitled "Over de theorie der terugkaatsing en breking van het licht" (On the theory of reflection and refraction of light), in which he refined the electromagnetic theory of James Clerk Maxwell.
In 1881 Hendrik married Aletta Catharina Kaiser, niece of Frederik Kaiser. She was the daughter of Johann Wilhelm Kaiser, director of the Amsterdam's Engraving School and professor of Fine Arts, and designer of the first Dutch postage stamps (1852). Later Kaiser was the Director of the National Gallery of Amsterdam. Hendrik and Aletta's eldest daughter Geertruida Luberta Lorentz was to become a physicist as well.

portrait by Jan Veth

Career

Professor in Leiden

In 1878, only 24 years of age, Hendrik Antoon Lorentz was appointed to the newly established chair in theoretical physics at the University of Leiden. On January 25 1878, he delivered his inaugural lecture on "De moleculaire theoriën in de natuurkunde" (The molecular theories in physics).

During the first twenty years in Leiden, Lorentz was primarily interested in the theory of electromagnetism to explain the relationship of electricity, magnetism, and light. After that, he extended his research to a much wider area while still focusing on theoretical physics. From his publications, it appears that Lorentz made contributions to mechanics, thermodynamics, hydrodynamics, kinetic theories, solid state theory, light, and propagation. His most important contributions were in the area of electromagnetism, the electron theory, and relativity.

Lorentz theorized that the atoms might consist of charged particles and suggested that the oscillations of these charged particles were the source of light. When colleague and former student of Lorentz Pieter Zeeman discovered the Zeeman effect in 1896, Lorentz supplied its theoretical interpretation. The experimental and theoretical work was honored with the Nobel prize in physics in 1902. Lorentz' name is now associated with the Lorentz-Lorenz formula, the Lorentz force, the Lorentzian distribution, and the Lorentz transformation.

Electrodynamics and relativity

Main articles: Lorentz ether theory and History of special relativity

In 1895, with the attempt to explain the Michelson-Morley experiment, Lorentz proposed that moving bodies contract in the direction of motion (see length contraction; George FitzGerald had already arrived at this conclusion, see FitzGerald-Lorentz Contraction). Lorentz worked on describing electromagnetic phenomena (the propagation of light) in reference frames that moved relative to each other. He discovered that the transition from one to another reference frame could be simplified by using a new time variable which he called local time. The local time depended on the universal time and the location under consideration. Lorentz's publications (of 1895 and 1899) made use of the term local time without giving a detailed interpretation of its physical relevance. In 1900, Henri Poincaré called Lorentz's local time a "wonderful invention" and illustrated it by showing that clocks in moving frames are synchronized by exchanging light signals that are assumed to travel at the same speed against and with the motion of the frame.

In 1899, and again in his paper Electromagnetic phenomena in a system moving with any velocity smaller than that of light (1904), Lorentz added time dilation to his transformations and published what Poincaré in 1905 named Lorentz transformations. It was apparently unknown to Lorentz that Joseph Larmor had used identical transformations to describe orbiting electrons in 1897. Larmor's and Lorentz's equations look somewhat unfamiliar, but they are algebraically equivalent to those presented by Poincaré and Einstein in 1905.[1] Lorentz's 1904 paper includes the covariant formulation of electrodynamics, in which electrodynamic phenomena in different reference frames are described by identical equations with well defined transformation properties. The paper clearly recognizes the significance of this formulation, namely that the outcomes of electrodynamic experiments do not depend on the relative motion of the reference frame. The 1904 paper includes a detailed discussion of the increase of the inertial mass of rapidly moving objects. In 1905, Einstein would use many of the concepts, mathematical tools and results discussed to write his paper entitled "Elektrodynamik" (Electrodynamics) known today as the theory of special relativity. Because Lorentz laid the fundamentals for the work by Einstein, this theory was called the Lorentz-Einstein theory originally.

Albert Einstein and Hendrik Antoon Lorentz, photographed by Ehrenfest in front of his home in Leiden in 1921. Source: Museum Boerhaave, Leiden

The increase of mass was the first prediction of special relativity to be tested, but from early experiments by Kaufmann it appeared that his prediction was wrong; this led Lorentz to the famous remark that he was "at the end of his Latin."[2] The confirmation of his prediction had to wait until 1908. In 1909, Lorentz published "Theory of Electrons" based on a series of lectures in Mathematical Physics he gave at Columbia University.[3]

Assessments

Poincaré (1902) said of Lorentz's theory of electrodynamics:

The most satisfactory theory is that of Lorentz; it is unquestionably the theory that best explains the known facts, the one that throws into relief the greatest number of known relations ... it is due to Lorentz that the results of Fizeau on the optics of moving bodies, the laws of normal and abnormal dispersion and of absorption are connected with each other ... Look at the ease with which the new Zeeman phenomenon found its place, and even aided the classification of Faraday's magnetic rotation, which had defied all Maxwell's efforts.

Paul Langevin (1911) said of Lorentz:

It is the great merit of H. A. Lorentz to have seen that the fundamental equations of electromagnetism admit a group of transformations which enables them to have the same form when one passes from one frame of reference to another; this new transformation has the most profound implications for the transformations of space and time

Lorentz and Emil Wiechert (Göttingen) had an interesting correspondence on the topics of electromagnetism and the theory of relativity, and Lorentz explained his ideas in letters to Wiechert. The correspondence between Lorentz and Wiechert has been published by Wilfried Schröder (Arch. ex. hist. Sci, 1984).

Lorentz was chairman of the first Solvay Conference held in Brussels in the autumn of 1911. Shortly after the conference, Poincaré wrote an essay on quantum physics which gives an indication of Lorentz's status at the time:

... at every moment [the twenty physicists from different countries] could be heard talking of the [quantum mechanics] which they contrasted with the old mechanics. Now what was the old mechanics? Was it that of Newton, the one which still reigned uncontested at the close of the nineteenth century? No, it was the mechanics of Lorentz, the one dealing with the principle of relativity; the one which, hardly five years ago, seemed to be the height of boldness.

Albert Einstein (1953) wrote of Lorentz:

For me personally he meant more than all the others I have met on my life's journey.[4]

While Lorentz is mostly known for fundamental theoretical work, he also had an interest in practical applications. In the years 1918-1926, at the request of the Dutch government, Lorentz headed a committee to calculate some of the effects of the proposed Afsluitdijk (Closure Dike) flood control dam on other seaworks in the Netherlands. Hydraulic engineering was mainly an empirical science at that time, but the disturbance of the tidal flow caused by the Afsluitdijk was so unprecedented that the empirical rules could not be trusted. Lorentz proposed to start from the basic hydrodynamic equations of motion and solve the problem numerically. This was feasible for a "human computer", because of the quasi-one-dimensional nature of the water flow in the Waddenzee. The Afsluitdijk was completed in 1933 and the predictions of Lorentz and his committee turned out to be remarkably accurate.[5] One of the two sets of locks in the Afsluitdijk was named after him.

Personal life

In 1912 Lorentz retired early to become director of research at Teylers Museum in Haarlem, although he remained external professor at Leiden and gave weekly lectures there. Paul Ehrenfest succeeded him in his chair at the University of Leiden, founding the Institute for Theoretical Physics which would become known as the Lorentz Institute. In addition to the Nobel prize, Lorentz received a great many honours for his outstanding work. He was elected a Fellow of the Royal Society in 1905. The Society awarded him their Rumford Medal in 1908 and their Copley Medal in 1918.

Lorentz died in Haarlem, Netherlands. The respect in which he was held in the Netherlands is apparent from O. W. Richardson's description of his funeral:

The funeral took place at Haarlem at noon on Friday, February 10. At the stroke of twelve the State telegraph and telephone services of Holland were suspended for three minutes as a revered tribute to the greatest man Holland has produced in our time. It was attended by many colleagues and distinguished physicists from foreign countries. The President, Sir Ernest Rutherford, represented the Royal Society and made an appreciative oration by the graveside. [6]

Legacy

Richardson describes Lorentz as:

[A] man of remarkable intellectual powers ... . Although steeped in his own investigation of the moment, he always seemed to have in his immediate grasp its ramifications into every corner of the universe. ... The singular clearness of his writings provides a striking reflection of his wonderful powers in this respect. .... He possessed and successfully employed the mental vivacity which is necessary to follow the interplay of discussion, the insight which is required to extract those statements which illuminate the real difficulties, and the wisdom to lead the discussion among fruitful channels, and he did this so skillfully that the process was hardly perceptible. [6]

M. J. Klein (1967) wrote of Lorentz's reputation in the 1920s:

For many years physicists had always been eager "to hear what Lorentz will say about it" when a new theory was advanced, and, even at seventy-two, he did not disappoint them. [7]

See also

References

Search Wikisource Wikisource has original works written by or about: Hendrik Lorentz
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Papers of Lorentz

There are thirty-six complete papers by Lorentz (mostly in English) that are available for online viewing in the Proceedings of the Royal Netherlands Academy of Arts and Science, Amsterdam.

  • Lorentz, Hendrik Antoon (1927-1931), Lectures on Theoretical Physics (vol. I-III), New York, [NY.]: Macmillan & Co. , (Vol. I online)
Other sources
  • de Haas-Lorentz, Geertruida L.; Fagginger Auer, Joh. C. (trans.) (1957), H.A. Lorentz: impressions of his life and work, Amsterdam: North-Holland Pub. Co. 
  • Langevin, Paul (1911), "L'évolution de l'espace et du temps", Scientia X: 31–54  :n.p.
  • Poincaré, Henri (1900), "La théorie de Lorentz et le principe de réaction", Archives Néerlandaises des Sciences exactes et naturelles V: 253–278  See English translation.
  • Poincaré, Henri (1902), La science et l'hypothèse, Paris, [France]: Ernest Flammarion  : n.p.. The quotation is from the English translation (Poincaré, Henri (1952), Science and hypothesis, New York, [NY.]: Dover Publications, p. 175 )
  • Poincaré, Henri (1913), Dernières pensées, Paris, [France]: Ernest Flammarion  :n.p.. The quotation in the article is from the English translation: (Poincaré, Henri; Bolduc, John W. (trans.) (1963), Mathematics and science: last essays, New York, [NY.]: Dover Publications  :n.p.)
  • Przibram, Karl (ed.); Klein, Martin J. (trans.) (1967), Letters of wave mechanics: Schrödinger, Planck, Einstein, Lorentz. Edited by Karl Przibram for the Austrian Academy of Sciences, New York, [NY.]: Philosophical Library  :n.p.
Endnotes
  1. ^ Macrossan 1986
  2. ^ Lorentz à Poincaré at web.archive.org
  3. ^ Lorentz 1909
  4. ^ Link
  5. ^ Carlo Beenakker
  6. ^ a b Richardson 1929
  7. ^ Przibram 1967

External links

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Nobel Laureates in Physics

Wilhelm Röntgen (1901) · Hendrik Lorentz / Pieter Zeeman (1902) · Henri Becquerel / Pierre Curie / Marie Curie (1903) · Lord Rayleigh (1904) · Philipp Lenard (1905) · J. J. Thomson (1906) · Albert Michelson (1907) · Gabriel Lippmann (1908) · Guglielmo Marconi / Ferdinand Braun (1909) · Johannes van der Waals (1910) · Wilhelm Wien (1911) · Gustaf Dalén (1912) · Kamerlingh Onnes (1913) · Max von Laue (1914) · W. L. Bragg / W. H. Bragg (1915) · Charles Barkla (1917) · Max Planck (1918) · Johannes Stark (1919) · Charles Guillaume (1920) · Albert Einstein (1921) · Niels Bohr (1922) · Robert Millikan (1923) · Manne Siegbahn (1924) · James Franck / Gustav Hertz (1925)


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