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Topic Review
Hidden Jahn-Teller and Pseudo-Jahn-Teller effects
The source of spontaneous symmetry breaking (SSB) in polyatomic systems, attributed to the Jahn-Teller effect (in electronic degenerate states) or to the pseudo-Jahn-Teller effect (under the condition of pseudodegeneracy), is complemented with the notions of hidden Jahn-Teller effect (h-JTE) and hidden pseudo-Jahn-Teller effect (h-PJTE) to stand for the cases when neither electronic degeneracy, nor pseudodegeneracy is present, but the system is still spontaneously distorted. The h-JTE and h-PJTE occur due to, respectively, the JTE and PJTE in the excited states of the undistorted system, but being strong enough, they penetrate its ground state forming a stable configuration with lower symmetry and (possibly) different spin.
  • 1.5K
  • 11 Dec 2020
Biography
Hermann Oberth
Hermann Julius Oberth (German: [ˈhɛrman ˈjuːli̯ʊs ˈoːbɛrt]; 25 June 1894 – 28 December 1989) was an Austro-Hungarian-born German physicist and engineer. He is considered one of the founding fathers of rocketry and astronautics, along with the French Robert Esnault-Pelterie, the Russian Konstantin Tsiolkovsky, and the American Robert Goddard.[1][2] Hermann Oberth as a young boy,
  • 1.1K
  • 05 Dec 2022
Biography
Herman Postma
Herman Postma (March 29, 1933 – November 7, 2004) was an American scientist and educational leader. Born in Wilmington, North Carolina, he moved to Oak Ridge, Tennessee, in 1959 after attending Duke, Harvard and MIT. Much of Postma's career was at Oak Ridge National Laboratory where he served as Laboratory Director from 1974 to 1988. Postma was born in Wilmington, North Carolina, on March 2
  • 717
  • 30 Dec 2022
Biography
Herman Carr
Herman Y. Carr (November 28, 1924 – April 9, 2008), who published as H. Y. Carr, was an American physicist and pioneer of magnetic resonance imaging. Dr. Carr was born in Alliance, Ohio where he was an Alliance High School graduate in January 1943; he later was inducted into their Hall of Fame. He served in the Army as a Sergeant in the 12th Weather Squadron Air Corps during World War II in It
  • 418
  • 08 Dec 2022
Topic Review
Hercules
Hercules is a prominent constellation in the northern celestial hemisphere, named after the legendary hero from Greek mythology known for his incredible strength and courage. It is the fifth-largest of the 88 modern constellations.
  • 403
  • 15 Mar 2024
Topic Review
Heliophysics NASA Science
Heliophysics is an aspect of NASA science that enables understanding the Sun, heliosphere, and planetary environments as a single connected system. In addition to solar processes, this domain of study includes the interaction of solar plasma and solar radiation with Earth, the other planets, and the galaxy. By analyzing the connections between the Sun, solar wind, and planetary space environments, the fundamental physical processes that occur throughout the universe are uncovered. Understanding the connections between the Sun and its planets will allow for predicting the impacts of solar interaction on humans, technological systems, and even the presence of life itself. This is also the stated goal of Science Mission Directorate's Heliophysics Research.
  • 248
  • 25 Oct 2022
Biography
Heinz Pagels
Heinz Rudolf Pagels (February 19, 1939 – July 23, 1988) was an United States physicist,[1] an adjunct professor of physics at Rockefeller University, the executive director and chief executive officer of the New York Academy of Sciences, and president of the International League for Human Rights. He wrote the popular science books The Cosmic Code (1982), Perfect Symmetry (1985), and The Dreams
  • 749
  • 02 Dec 2022
Biography
Heinz Maier-Leibnitz
Heinz Maier-Leibnitz (28 March 1911 in Esslingen am Neckar – 16 December 2000 in Allensbach) was a Germany physicist.[1] He made contributions to nuclear spectroscopy, coincidence measurement techniques, radioactive tracers for biochemistry and medicine, and neutron optics. He was an influential educator and an advisor to the Federal Republic of Germany on nuclear programs. During World War I
  • 754
  • 09 Dec 2022
Biography
Heinrich Rubens
Heinrich Rubens (30 March 1865, Wiesbaden, Nassau, Germany – 17 July 1922, Berlin, Germany) was a German physicist. He is known for his measurements of the energy of black-body radiation which led Max Planck to the discovery of his radiation law. This was the genesis of quantum theory. After having attended realgymnasium Wöhlerschule in Frankfurt am Main, he started in 1884 to study electric
  • 442
  • 09 Dec 2022
Biography
Hedwig Kohn
Hedwig Kohn (5 April 1887 – 26 November 1964) was a physicist who was one of only three women (along Lise Meitner and Hertha Sponer) to obtain habilitation (the qualification for university teaching) in physics in Germany before World War II. Born in Breslau in the German Empire (now Wrocław, Poland ), she was forced to leave Germany during the Nazi regime because she was Jewish. She continue
  • 883
  • 22 Nov 2022
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