• Professor Ali Hani Chamseddine

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    Ali H. Chamseddine is Professor of Theoretical Physics at the American University of Beirut since 1998. He earned his B.Sc. in Physics from the Lebanese University in 1973 and won a scholarship to pursue graduate study in theoretical physics at Imperial College, London University. He earned his Ph.D. in 1976 with the Nobel Laureate Abdus Salam as his thesis advisor. He has research appointments at the International Center for Theoretical Physics (ICTP), Trieste, Italy, (1977) the European Organization for Nuclear Research (CERN), Geneva, Switzerland (1980, 1987) and Northeastern University, Boston, USA (1981-1985). He worked as Research Professor at the University of Zurich and the Swiss Federal Institute of Technology (ETH), Zurich, Switzerland (1986-1998).


    Dr. Chamseddine has many pioneering contributions in supersymmetry and noncommutative geometry and gravity. His research centers on unification of all fundamental forces in nature and the underlying symmetry principle and geometric structure of space-time. His work is noted for its mathematical elegance and originality


    In 1982, as a research associate at Northeastern University and in collaboration with Drs. Richard Arnowitt and Pran Nath, he constructed a locally supersymmetric model based on the unification of gravity with the three fundamental forces nature. This Locally Supersymmetric Grand Unification had enormous influence on the field and is used since 2012 by the Large Hadron Collider (LHC) for the search of the predicted supersymmetric particles.


    In 1996, Professor Chamseddine, in collaboration with the Field Medalist Alain Connes proposed a new physical principle which they coined "The Spectral Action Principle" linking the spectrum of a differential operator with the geometric invariants of the space. This principle allowed them to discover the hidden noncommutative structure of space time from the known spectrum of elementary particles. More recently they were able to explain the Standard Model of Particle Physics from a generalization of Heisenberg uncertainty relations.


    Dr. Chamseddine was the founding director of the Center for Advanced Mathematical Sciences (1998-2003) and has served on the editorial boards of several journals. Among his honors are the Humboldt Research Prize (2001), the Bode Medal (2007) and the TWAS (Academy of Science for Developing Countries) Physics Prize (2009).


    Professor Chamseddine was elected to the ASL in 2015 for "ground-breaking developments in theories of gravity and space-time, and in our understanding of the essence of the physical universe."

    Sample of Academician's Research

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    The diagram describes the symmetries of the building blocks of matter. The 16 fundamental fermions comprised of quarks and leptons are grouped in the form (4, 4) where the first 4 is acted on by M4 (C), the algebra of 4x4 complex matrices, representing the three colors of the quarks with the lepton number considered as the fourth color. The second group of 4 is acted on by M2 (H), the algebra of 2x2 quaternion matrices (a quaternion number has one real and three imaginary parts). By chirality, this 4 is broken as 2+2 of left-handed and right-handed representations. This implies that the leptons comprising the electron and neutrino form a doublet, each having a left and right component. Similarly, the quarks come in doublets, up and down, with left and right components. These algebras in turn dictate the structure of the vector interactions governing the three fundamental forces in nature, weak, electromagnetic, and strong. The symmetries in the diagram are a consequence of a new geometric structure of space-time, named noncommutative geometry, inspired by quantum mechanics, allowing for simultaneous treatment of the discrete and continuous. Professor Chamseddine and his collaborators have provided an attractive geometrical explanation for the building blocks in nature and their interactions. More recently they have identified a more basic entity, the Quanta of Geometry.

  • Professor Edgar Choueiri

    (ASL President 2008-2014)

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    Professor Edgar Choueiri is Director of Princeton University's Program in Engineering Physics, and Chief Scientist and Director of Princeton's Electric Propulsion and Plasma Dynamics Laboratory (EPPDyL). He is Professor in the Applied Physics Group at the Mechanical and Aerospace Engineering Department, and Associated Faculty at the Astrophysical Sciences Dept./Program in Plasma Physics at Princeton University. He holds a PhD in Aerospace Engineering/Plasma Science (1991) from Princeton University.


    He has been the Principle Investigator (PI) in charge of directing and managing more than 25 competitively selected research projects, funded by NASA, AFOSR, the National Science Foundation, and other governmental and private institutions. He has been PI and Co-PI on two space experiments onboard the Space Shuttle and the Russian scientific spacecraft APEX. Professor Choueiri's laboratory (EPPDyL) at Princeton University, a recognized center of excellence in research in the field of advanced spacecraft propulsion, has been continuously funded by NASA since he became EPPDyL's Chief Scientist in 1996.


    Professor Choueiri's main research interests are in astronautics and plasma physics, and he is the author of more than 140 journal articles, conference papers and encyclopedia articles on plasma propulsion for spacecraft, plasma physics, instabilities and turbulence in collisional plasmas, plasma accelerator modeling, space physics and applied mathematics. He has been an invited speaker at symposia and leading institutions in more than 20 countries and has advised more than a hundred graduate and undergraduate students at Princeton University. Many of his PhD students are in leading positions as research scientists in plasma physics or space propulsion. He serves as Associate Editor of the Journal of Propulsion and Power, the leading journal for spacecraft propulsion.


    He is the recipient of a number of awards and honors, including the Howard B. Wentz Award for Excellence in Teaching and Scholarship and the Medal of the Order of the Cedars (rank of Knight), and was elected President of the Electric Rocket Propulsion Society, whose members include hundreds of scientists working on plasma propulsion for spacecraft in more than 15 countries. He served as the elected Chair of the American Institute of Aeronautics and Astronautics' Electric Propulsion Technical Committee (EPTC) from 2002 to 2004, the leading professional society in his field, was awarded the AIAA's distinguished service award in 2004 elected Fellow of the AIAA in 2009.


    He was selected by NASA in 2004 as the winner of a competition to lead a team of NASA and academic researchers on a 3-year research project to develop a high-power plasma rocket system intended for the robotic and human exploration of the Moon and Mars.


    Professor Choueiri is a founding member of the ASL and served as its Founding President from June 27, 2008 to January 31, 2014.

    Sample of Academician's Research

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    Poincaré map for the nonlinear interaction between a magnetized ion and two beating electrostatic waves, showing the elliptic and hyperbolic points whose locations allowed Prof. Choueiri and his student Slava Spektor to find the necessary and sufficient conditions for the existence of a highly efficient mechanism for ion acceleration that is being used in the development of a new class of plasma rockets for spacecraft intended for deep space exploration.

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    FARAD (which stands for Faraday Accelerator with Radio-frequency Assisted Discharge) is an electrode-less plasma propulsion concept devised by Professor Choueiri for long-life efficient propulsion of spacecraft. It is presently being developed by scientists at NASA and industry.

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  • Dr. Charles Elachi

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    Dr. Charles Elachi (born April 18, 1947 in Lebanon) is the Director of NASA's Jet Propulsion Laboratory (JPL) and vice president of the California Institute of Technology. Dr. Elachi received a bachelor's degree (1968) in physics from University of Grenoble, France; the Diplome Ingenieur (1968) in engineering from the Polytechnic Institute, Grenoble; and a master's degree (1969) and doctorate (1971) in electrical sciences from the California Institute of Technology, Pasadena. He also has a master's degree (1983) in geology from the University of California, Los Angeles, and an MBA (1979) from the University of Southern California. He joined JPL in 1970. He is professor of electrical engineering and planetary science at Caltech.


    Dr. Elachi has been a principal investigator on a number of research and development studies and flight projects sponsored by NASA. These include the Shuttle Imaging Radar series (science team leader), the Magellan imaging radar at Venus (team member), and the Cassini Titan radar (team leader). He is author of more than 230 publications in the fields of active microwave remote sensing and electromagnetic theory, and holds several patents in those fields. He taught the physics of remote sensing at Caltech from 1982 to 2001.


    As JPL's director for space and Earth science programs from 1982 to 2000, Dr. Elachi was responsible for the development of numerous flight missions and instruments for Earth observation, planetary exploration, and astrophysics.


    In 1988, the Los Angeles Times selected Dr. Elachi as one of "Southern California's rising stars who will make a difference in L.A." In 1989, asteroid 1982 SU was renamed 4116 Elachi in recognition of his contribution to planetary exploration. In 1989, he was elected to the National Academy of Engineering and has served on a number of academy committees.


    Dr. Elachi has chaired a number of strategic planning committees for NASA. He has lectured in more than 20 countries about space exploration and Earth observation. He participated in a number of archeological expeditions in Egypt, Oman and China.


    His numerous awards have included being honored as one of "America's Best Leaders" by U.S. News & World Report (2006), in collaboration with the Center for Public Leadership at Harvard University's John F. Kennedy School of Government, the Royal Society of London's Massey Award (2006), Lebanon's Order of Cedars (2006), the American Task Force for Lebanon's Philip Habib Award for Distinguished Public Service (2006), the American Astronautical Society's Space Flight Award (2005), the National Defense Industrial Association's Bob Hope Distinguished Citizen Award (2005), NASA Exceptional Service Medal (2005), NASA Outstanding Leadership Medal (2004, 2002, 1994), NASA Exceptional Scientific Achievement Medal (1982), NASA Distinguished Service Medal (1999), the Takeda Award (2002), the Wernher von Braun Award (2002), Dryden Award (2000), the Committee on Space Research's Nordberg Medal (1996), the Nevada Medal (1995), the Institute of Electrical and Electronics Engineers' Medal of Engineering Excellence (1992) and Geoscience and Remote Sensing Distinguished Achievement Award (1987), the W. T. Pecora Award (1985), and the American Society for Photogrammetry and Remote Sensing's Autometric Award (1980 and 1982). He is a fellow of the Institute of Electrical and Electronics Engineers and the American Institute of Aeronautics and Astronautics, and a member of the National Academy of Engineering and the International Academy of Astronautics.


    Dr. Elachi was elected to the ASL in 2009.

    Sample of Academician's Research

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    The legendary city of Ubar, a desert caravansary, which supported the ancient and lucrative frankincense trade, perished in the early part of the first millenium AD.


    Legend was that Ubar perished in a sandstorm as divine punishment for wicked living. Actually, much of the fortress collapsed into a sinkhole, perhaps by ground water withdrawal used to irrigate the surrounding oasis

    The archaeological site was located by Dr. Elachi and his co-wokers at the edge of the Arabian Peninsula's Empty Quarter modern day Oman, through an unusual combination of historical research, and application space technology, in support of traditional archaeology.


    The discovery was made possible through the use of advanced remote sensing instruments (flown in the space shuttle) pioneered and developed by Dr. Elachi and his group at JPL.


    The picture above, obtained with Dr. Elachi's radar instruments from the space shuttle, shows the actual site of the fortress of the lost city of Ubar to be near the Wadi (white band across the image) close to the center of the image.


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