Theodor des Coudres (13 March 1862 in

Veckerhagen Reinhardshagen is a municipality in the district of Kassel, in Hesse, Germany. It is located 24 kilometers north of Kassel, and 21 kilometers west of Göttingen Göttingen (, , ; nds, Chöttingen) is a university city in Lower Saxony, cent ...

, Weser – 8 October 1926 in

Leipzig Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as wel ...

) was a

German German(s) may refer to: * Germany (of or related to) ** Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ge ...

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate caus ...

. Theodor des Coudres was the son of Julius des Coudres and his wife Anna Henrietta Rosenstock. His younger brother, Richard des Coudres, later became president of the "Mitteldeutschen Sängerbundes" (Central German singer federation); his uncle on the paternal side was the painter

Ludwig des Coudres Ludwig des Coudres (10 May 1820, Kassel - 23 December 1878, Karlsruhe) was a German history and portrait painter. He also served as a Professor at the Academy of Fine Arts, Karlsruhe. His son, Adolf Des Coudres, was a well-known landscape pa ...

. In 1881 des Coudres began to study

natural science Natural science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer review and repeatab ...

and

medicine Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pract ...

at the

University of Geneva The University of Geneva (French: ''Université de Genève'') is a public research university located in Geneva, Switzerland. It was founded in 1559 by John Calvin as a theological seminary. It remained focused on theology until the 17th centu ...

and later in

and

Munich Munich ( ; german: München ; bar, Minga ) is the capital and most populous city of the States of Germany, German state of Bavaria. With a population of 1,558,395 inhabitants as of 31 July 2020, it is the List of cities in Germany by popu ...

. At the

Humboldt University of Berlin Humboldt-Universität zu Berlin (german: Humboldt-Universität zu Berlin, abbreviated HU Berlin) is a German public research university in the central borough of Mitte in Berlin. It was established by Frederick William III on the initiative o ...

in 1887, he successfully finished his study with a thesis on the optical constants of

mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

with Professor

Hermann von Helmholtz Hermann Ludwig Ferdinand von Helmholtz (31 August 1821 – 8 September 1894) was a German physicist and physician who made significant contributions in several scientific fields, particularly hydrodynamic stability. The Helmholtz Association, ...

. 1889 he was employed at the

University of Leipzig Leipzig University (german: Universität Leipzig), in Leipzig in Saxony, Germany, is one of the world's oldest universities and the second-oldest university (by consecutive years of existence) in Germany. The university was founded on 2 Decemb ...

as an assistant of Professor

Gustav Heinrich Wiedemann Gustav Heinrich Wiedemann (; 2 October 1826 – 24 March 1899) was a German physicist and scientific author. Life Wiedemann was born in Berlin the son of a merchant who died two years later. Following the death of his mother in 1842 he lived wi ...

. His research led him to his

Habilitation Habilitation is the highest university degree, or the procedure by which it is achieved, in many European countries. The candidate fulfills a university's set criteria of excellence in research, teaching and further education, usually including a ...

in 1891. 1895 he was appointed to the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...

at the chair for "applied electricity". In 1901 he went to the

University of Würzburg The Julius Maximilian University of Würzburg (also referred to as the University of Würzburg, in German ''Julius-Maximilians-Universität Würzburg'') is a public research university in Würzburg, Germany. The University of Würzburg is one of ...

and took over the chair for

theoretical physics Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experim ...

as an extraordinary professor. In 1903 he became the successor of Professor

Ludwig Boltzmann Ludwig Eduard Boltzmann (; 20 February 1844 – 5 September 1906) was an Austrian physicist and philosopher. His greatest achievements were the development of statistical mechanics, and the statistical explanation of the second law of thermodyn ...

at the

, where he worked until the end of his life. Sometimes he suffered from an enormous

writer's block Writer's block is a condition, primarily associated with writing, in which an author is either unable to produce new work or experiences a creative slowdown. Mike Rose found that this creative stall is not a result of commitment problems or th ...

and could handle this problem only during long trips by

railway Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a pre ...

. Theodor des Coudres died in Leipzig on 8 October 1926 at the age of 64 years. The publisher

Georg Hirzel Georg may refer to: * ''Georg'' (film), 1997 * Georg (musical), Estonian musical * Georg (given name) * Georg (surname) * , a Kriegsmarine coastal tanker See also * George (disambiguation) {{disambiguation ...

and the physicist Otto Wiener wrote noteworthy obituaries on Theodor des Coudres. Des Coudres worked among other things on metal reflection, the

Kerr effect The Kerr effect, also called the quadratic electro-optic (QEO) effect, is a change in the refractive index of a material in response to an applied electric field. The Kerr effect is distinct from the Pockels effect in that the induced index chang ...

high pressure physics In science and engineering the study of high pressure examines its effects on materials and the design and construction of devices, such as a diamond anvil cell, which can create high pressure. By ''high pressure'' is usually meant pressures of t ...

, and he was the first to determine the specific

charge Charge or charged may refer to: Arts, entertainment, and media Films * '' Charge, Zero Emissions/Maximum Speed'', a 2011 documentary Music * ''Charge'' (David Ford album) * ''Charge'' (Machel Montano album) * ''Charge!!'', an album by The Aqu ...

and the speed of

alpha particle Alpha particles, also called alpha rays or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to a helium-4 nucleus. They are generally produced in the process of alpha decay, but may also be produce ...

References

{{DEFAULTSORT:Des Coudres, Theodor 1862 births 1926 deaths 19th-century German physicists Academic staff of Leipzig University 20th-century German physicists