Heinrich Hertz

Pioneering German physicist Heinrich Rudolf Hertz was born February 22, in 1857. He expanded on the electromagnetic theory of light which had been put forth by Maxwell & was the first to prove the existence of electromagnetic waves by engineering instruments to transmit and receive radio pulses using experimental procedures that eliminated other known wireless phenomena. He studied at the Gelehrtenschule des Johanneums in Hamburg, and showed an aptitude for sciences as well as languages, learning Arabic and Sanskrit. He also studied sciences and engineering in the German cities of Dresden, Munich and Berlin, where he studied under Gustav R. Kirchhoff and Hermann von Helmholtz. In 1880, Hertz obtained his PhD from the University of Berlin; and remained for post-doctoral study under Hermann von Helmholtz. In 1883, Hertz became a lecturer in theoretical physics at the University of Kiel, and In 1885, Hertz became a full professor at the University of Karlsruhe where he discovered electromagnetic waves. The most dramatic prediction of Maxwell’s theory of electromagnetism, published in 1865, was the existence of electromagnetic waves moving at the speed of light, and the conclusion that light itself was just such a wave. This challenged experimentalists to generate and detect electromagnetic radiation using some form of electrical apparatus.

The first clearly successful attempt was made by Heinrich Hertz in 1886. For his radio wave transmitter he used a high voltage induction coil, a condenser (capacitor, Leyden jar) and a spark gap — whose poles on either side are formed by spheres of 2 cm radius — to cause a spark discharge between the spark gap’s poles oscillating at a frequency determined by the values of the capacitor and the induction coil. Hertz also had a deep interest in meteorology probably derived from his contacts with Wilhelm von Bezold (who was Hertz’s professor in a laboratory course at the Munich Polytechnic in the summer of 1878). Hertz, however, did not contribute much to the field himself except some early articles as an assistant to Helmholtz in Berlin, including research on the evaporation of liquids, a new kind of hygrometer, and a graphical means of determining the properties of moist air when subjected to adiabatic changes.

Between 1886 and 1889, Hertz published two articles on the field of contact mechanics and is well known for his contributions to the field of electrodynamics, his two papers were a source for some important ideas and established that contact mechanics is of immense importance. His work basically summarises how two axi-symmetric objects placed in contact will behave under loading, he obtained results based upon the classical theory of elasticity and continuum mechanics. In 1886, Hertz developed the Hertz antenna receiver, He also developed a transmitting type of dipole antenna for transmitting UHF radio waves. In 1887, Hertz experimented with radio waves in his laboratory. These actions followed Michelson’s 1881 experiment, which did not detect the existence of aether drift. Hertz altered the equations to take this view into account for electromagnetism. Hertz published his work in a book titled: Electric waves: being researches on the propagation of electric action with finite velocity through space.

Sadly after undergoing surgery to treat Wegener’s granulomatosis on January 1, 1894 at the age of 36 in Bonn, Germany and was buried in Ohlsdorf, Hamburg at the Jewish cemetery. His nephew Gustav Ludwig Hertz was also a Nobel Prize winner, and Gustav’s son Carl Hellmuth Hertz invented medical ultrasonography. The SI unit hertz (Hz) was established in his honor by the IEC in 1930 for frequency, an expression of the number of times that a repeated event occurs per second. It was adopted by the CGPM (Conférence générale des poids et mesures) in 1960, officially replacing the previous name, the “cycle per second” (cps). In 1969 (East Germany), a Heinrich Hertz memorial medal 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”.A crater that lies on the far side of the Moon, is named in his honor. The Hertz market for radioelectronics products in Nizhny Novgorod, Russia, is named after him. The Heinrich-Hertz-Turm radio telecommunication tower in Hamburg is named after the city’s famous son. Hertz is honored by Japan with a membership in the Order of the Sacred Treasure, which has multiple layers of honor for prominent people, including scientists. Heinrich Hertz has been honored by a number of countries around the world in their postage issues, and in post-World War II times has appeared on various German stamp issues as well.

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