Ragnar Holm

Ragnar Holm (born 6 May 1879 in Skara, Sweden, died on 27 February 1970 at St. Marys, Pennsylvania, USA), was a Swedish physicist and researcher in electrical engineering, who was partially active in Germany and the United States.^[1]

In 1904, Holm became licentiate in philosophy (PhL) at Uppsala University, and earned his PhD in 1908.^[2] From 1906 to 1908 he studied at the University of Göttingen in Germany. In 1908 to 1909 he was a lecturer in Stockholm. Between 1909 and 1919 he worked as a physicist for Siemens & Halske in Berlin. In 1919 to 1921 he was a physicist and teacher at the Telegraphic Education Center in Stockholm, and between 1921 and 1927 associate professor at the Technical High School in Örebro. Between 1927 and 1945 he worked again for Siemens & Halske. From 1947 he was a consulting physicist at Stackpole Carbon Company in St. Marys, Pennsylvania.

Holm's research area included the study of electrical discharges, but his main focus was on electrical contacts, where he was a world-leading authority. His book Electric Contacts, originally published in 1946,^[3] is still used as a standard work in the field (in its fourth edition of 1967).^[4][5]

He also made significant contributions to the field of tribology, specifically predicting wear.^[6]

The Swedish Library of the Royal Institute of Technology (KTHB) maintains a special literature collection (Holm Collection) related to Ragnar Holm's research.^[7]

With Walther Meissner, he published a seminal work in 1932 on contacts between superconductors and normal conductors.^[8] This led to the discovery of the proximity effect, sometimes known as the Holm–Meissner effect. This discovery led to the invalidation of Albert Einstein model for superconductivity.^[8]

En 1963, Holm recibió el Premio Internacional de la Sociedad de Tribólogos e Ingenieros de Lubricación . ^{[ 9 ]} En 1968, recibió el Premio Mayo D. Hersey de la Sociedad Estadounidense de Ingenieros Mecánicos . ^{[ 10 ]}

Holm falleció el 27  de febrero de 1970 en su casa de St. Marys, Pensilvania. Su funeral se celebró en Suecia, en la Catedral de Skara, el 14  de agosto de 1970, donde fueron inhumadas sus cenizas. ^{[ 11 ]} Se publicó una necrología de Holm en Physics Today ( Instituto Americano de Física ). ^{[ 12 ]} En 1971, un año después de la muerte de Holm, el IEEE estableció el Premio Ragnar Holm a la Trayectoria Científica ("Premio Ragnar Holm") por sus contribuciones en el campo de los contactos eléctricos. El premio se ha otorgado anualmente desde 1972. ^{[ 13 ]}

Desde 1999, el Real Instituto de Tecnología de Suecia (KTH) otorga la placa Ragnar Holm a un joven físico al inicio de su carrera investigadora, tras evaluar sus tesis y artículos de física, principalmente relacionados con la investigación previa de Holm sobre contactos eléctricos. Cada dos años, la placa se concede a un sueco, y cada dos años la selección es internacional.

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