Ernest William Brown

Ernest William Brown FRS (29 November 1866 – 22 July 1938) was an English-born American mathematician and astronomer, famous for his research on lunar and planetary motions, as well as the orbits of the Trojan asteroids. His Tables of the Motion of the Moon (1919, Yale University Press), written with the assistance of Henry Benjamin Hedrick, was highly acclaimed. Among his many honours, Brown was elected in 1898 to both the Royal Society of London and the American Philosophical Society, in 1912 to the American Academy of Arts and Sciences, and in 1923 to the U.S. National Academy of Sciences.

Quotes

The general problem of Celestial Mechanics consists in the determination of the relative motions of p bodies attracting one another according to the Newtonian law. The problem is not able to be solved directly: in order to deal with it, certain limitations must be made.
- An Introductory Treatise on the Lunar Theory. Cambridge at the University Press. 1896. p. 2. (292 pages)

This story of the smaller bodies which form part of the solar system belongs altogether to the nineteenth and twentieth centuries. The discovery of Ceres on the first of January, 1801, followed by that of Pallas, Juno and Vesta, in the next six years, gave promise of a new field for the astronomer. Nearly forty years, however, elapsed before any more were found. The improvements in star maps about the middle of the century enabled observers to detect new objects more easily, so that from 1845 to 1860 over sixty were captured. Since that time scarcely a month but brings one or more to the list, and now nearly 700 are known. But this by no means completes the tale. New asteroids are constantly being recorded and receive a temporary designation and are perhaps observed two or three times. In fact the number of new discoveries has become too great for the few astronomers interested to obtain orbits of sufficient accuracy for future observation.
- (January 20, 1911) "The relations between Jupiter and the asteroids". Science 33 (838): 79–93.

The Ahmes Papyrus, which is dated some 1500 B. C., shows that the Egyptians had not only constructed an arithmetic but had started the solution of what we now call equations of the first degree with one unknown. There was no general method for solving the problems and although symbols for addition, subtraction, and equality occur, these were little used. In geometry they were also somewhat in advance of the Babylonians, apparently on account of practical needs in land surveying. It is generally agreed that the pyramids show evidence of astronomical observation in their orientation with respect to the stars, and they certainly show evidence of a knowledge of geometrical form. As these monuments appear to go back some 4000 years B. C., we have evidence of considerable development much further back even than the times indicated by the Babylonian tablets or the Ahmes Papyrus.
- "Chapter I. Mathematics". "'The Development of the Sciences''. 6 chapters from 6 different lectures delivered in 1920 at Yale University by Ernest William Brown, Henry Andrews Bumstead, John Johnston, Frank Schlesinger, Herbert Ernest Gregory, & Lorande Loss Woodruff. Yale University Press. 1923. pp. 1–42. (327 pages; edited by Lorande Loss Woodruff; quote from p. 7)

Differential geometry is in its essence a study of the properties of geometrical figures by investigating the properties of small elements of those figures. Such properties as curvature of a single curve or surface, and those which depend on classes, such as the envelope of a system of curves, the surfaces which cut systems of surfaces at right angles, are the natural subjects of investigation under this head. In 1828 Gauss published a memoir which immensely extended the range of this subject, by introducing new ideas which have been applied to such topics as the deformation of surfaces under given conditions and more particularly to those properties which remained unchanged by deformation. The subject is closely allied to many problems in physics.
- p. 28

Encyclopedic article on Ernest William Brown on Wikipedia
* Frank Schlesinger & Dirk Brouwer (1941) . "Biographical Memoir of Ernest William Brown 1866–1938". Biographical Memoirs of the U.S. National Academy of Sciences XXI: 243–273.