A TRIBUTE TO GREAT MUSLIM SCIENTISTS 5


AL-HAITHAM


Abu ali hasan Ibn al-Haitham was one of the most eminent physicists, whose contributions to optics and the scientific methods are outstanding known in the west as alhazen. Ibn al-Hautham was born in 965 A.D. in Basrah, and was educated in Basrah and haghdad. Thereafter. he went to Egypt, where he was asked to find ways of controlling the flood of the Nile. Being unsuccessful in this, he feigned madness until the death of Caliph al-Hakim, he also traveled to spain and during this period. he had ample time for his scientific pursuits, which included optics, mathematics, physics, medicine and devlopment of scientific methods on each of which he has left wveral outstanding books. he made a thorough examination of the passage of light through various media and discovered the laws of refraction. he also carried out the firs experiments on the dispersion of light into its constituent colors. His book Kitab-at-Manazir was translated into Latin in the Middle ages, as also his book delaing with the colors of sunset. He dellt at length with the theory of various physical phenomena like shadows, eclipses, the rainbow, and speculated on the physical nature of light. He is the first to describe accuratley the various parts of the eye and give a scientific explanation of the process of vision. he also attempted to explain binoclular vision, and gave a correct explanation of the apparent increase in size of the sun and the moon when near the horizon. He is known for the earlist use of the camera obscura. He contradicted ptolemy's and Euclid's theory of vision that objects are seen by rays of light emanating from the eyes. according to hin the rays originate in the object of vision and not in th eyee. Through thsese extensive researches on optics, he has been considered as the father of modern optics. the Latin translation of his main work, Kitab-ato-Manazir, exerted a great influence upon western science e.g. on the work on Roger Bacon and Kepler. It brought about a great progress in experimental methods. his research in catoptrics centrered on spherical and parabolic mirrors and spherical aberration. He made the important observation that the radio between the angle of incidence and refraction does not remain constant and investigated the magnifying power of a lens. His catoprics contain the important problem known as Alhazen's problem It comprises drawing lenes from two pionts in the plane of a circle meeting at a point on the circumference and making equal angles with the normal at that point. this leads to an equation of the fouth degree. in his book Mizan al-Hikmah Ibn alk-Haitham has discussed the density of the atmosphere refraction, he discovered that the twilight only ceases or begins when the sun is 19 below the horizon and attempted to measure the ghight of the atompsphere on the basis, he has also discussed the theories of attraction between masses, andit seems that he was aware of the magnitude of accleeration due to gravity. His contribution to mathematics and physics was wxtensive. in mathematics, he developed analytical geometry by establishing linkage between algebra and geometry. He studied the mechanics of motion of a body and was the first to maintain that a body moves perpetualoly unless an external force stops it of changes its dirction of motion. Thsi wold seem equivalent to the first law of motion. The list of his books runs to 200 or so, very few of which have survived. Even his monumental treatise on optics surived through its latin Translation. During the Middle ages his books on cosmology were translated into Latin. Hebrew and othe rlanguages. He has also written on the subject of evolution a book that deserves serious attention even tody. in his writing. one can see a clear devleopment of the scientfici methods as devvloped and applied by the Muslims and comprising the systmeatic obervation of physical phenomena and their linking together into a scientific theory. Thsi was a major breakthrough in scientific methodology, as distinct from guess gesture, and placed scientific pursutits on a sound foundation comprising systematic realtionshop between obervation, bypothesis and verifiction. Ibn al-Haitham'a influence on physical sciences in general and optics in particular, has been held in high esteem and in fact, it ushered in a new era in optical reserach, both in theory and practice. 


(Created By Dr. Jamal-ud-din khan MBBS )