Ari Ben-Menahem (Schlanger) has been professor of

mathematics Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...

and

geophysics Geophysics () is a subject of natural science concerned with the physical processes and physical properties of the Earth and its surrounding space environment, and the use of quantitative methods for their analysis. The term ''geophysics'' som ...

at the

Weizmann Institute of Science The Weizmann Institute of Science ( he, מכון ויצמן למדע ''Machon Vaitzman LeMada'') is a public research university in Rehovot, Israel, established in 1934, 14 years before the State of Israel. It differs from other Israeli unive ...

since 1964 and visiting professor at MIT. He is a

seismologist Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other ...

, author,

polymath A polymath ( el, πολυμαθής, , "having learned much"; la, homo universalis, "universal human") is an individual whose knowledge spans a substantial number of subjects, known to draw on complex bodies of knowledge to solve specific pro ...

, and historian of science. He coauthored with Sarvajit Singh, "Seismic Waves and Sources: the mathematical theory of seismology", a pioneering treatise since the nascent of this discipline at the turn of the 20th century. Ben-Menahem was born in Berlin, Germany on November 4, 1928. He received his master's degree in physics in 1954 from the

Hebrew University of Jerusalem The Hebrew University of Jerusalem (HUJI; he, הַאוּנִיבֶרְסִיטָה הַעִבְרִית בִּירוּשָׁלַיִם) is a public research university based in Jerusalem, Israel. Co-founded by Albert Einstein and Dr. Chaim Weiz ...

and his doctoral degree from the

California Institute of Technology The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...

(CIT) in 1961. He did his post-doctoral research at CIT, where he worked with Hugo Benioff and Frank Press (1962-1965). In his doctoral thesis he pioneered the birth of modern seismic-source elastodynamics based on his theory of wave radiation from a finite rupturing fault with subshear or supershear velocity. His theory was confirmed through the observed asymmetric radiation of long-period surface-waves from the great Chilean earthquake of May 22, 1960, where he introduced the fundamental concepts of 'Directivity' and 'Potency' from which the moment tensor is derived. Since then, rupturing fault length, rupture velocity, moment-magnitude and moment energy are routinely calculable from spectra of recorded seismic waves-forms. In 1975, Ben-Menahem used seismic and barometric recording of the

Tunguska event The Tunguska event (occasionally also called the Tunguska incident) was an approximately 12-megaton explosion that occurred near the Podkamennaya Tunguska River in Yeniseysk Governorate (now Krasnoyarsk Krai), Russia, on the morning of June 30, ...

of June 30, 1908, to derive the height and energy of the explosion, demonstrating for the first time a feasible non-cometary mechanism of this extraterrestrial bolide encounter with earth. Ben-Menahem is the sole author of a 6-volume, 6000 pages treatise: ''Historical Encyclopedia of Natural and Mathematical Sciences'' published in 2009 by Springer Verlag.

Selected publications

* Seismic Waves and Sources, Springer Verlag N.Y 1981, 1108 pp. * Seismic Waves and Sources, 2nd edition, Dover Publications, NY, 2000 * Vincint Veritas – A portrait of the life and work of N.A Haskell, Am. Geoph. Union, Washington D.C 209pp, 1990 *

Notes

External links

* {{DEFAULTSORT:Ben-Menahem, Ari Living people Israeli physicists Geophysicists Hebrew University of Jerusalem alumni California Institute of Technology alumni Jewish physicists 1928 births German emigrants to Mandatory Palestine 20th-century German Jews