Leon Brillouin – författare

Scientific Uncertainty and Information focuses on the validation of theories developed in physics, chemistry, biology, and other fields of science. The book first elaborates on thermodynamics, statistics, and information and the importance of scientific laws. Discussions focus on the importance and value of theories, empirical and theoretical laws, scientific laws and negentropy, principles of thermodynamics, entropy and value, negentropy, and energy degradation, and thermodynamics and information theory. The text then ponders on mathematical theorems and physical theories, imagination and invention in a theory, and causality and determinism. The manuscript underscores the weaknesses and limitations of mechanics and Poincare and the shortcomings of the Hamilton-Jacobi method for classical or quantized mechanics. Topics include the discussion of a simple example with two variables; degeneracy conditions and the possibility of finding a Hamilton-Jacobi transformation function; approximations for nondegenerate systems; methods of analytical dynamics for separated variables; and the objective world and the problem of determinism. The publication is a dependable reference for researchers interested in the validation of theories in science.

Wave Propagation and Group Velocity contains papers on group velocity which were published during the First World War and are missing in many libraries. It introduces three different definitions of velocities: the group velocity of Lord Rayleigh, the signal velocity of Sommerfeld, and the velocity of energy transfer, which yields the rate of energy flow through a continuous wave and is strongly related to the characteristic impedance. These three velocities are identical for nonabsorbing media, but they differ considerably in an absorption band. Some examples are discussed in the last chapter dealing with guided waves, and many other cases of application of these definitions are quoted. These problems have come again into the foreground, in connection with the propagation of radio signals and radar. Reflection in the Heaviside layers requires a real knowledge of all these different definitions. Group velocity also plays a very important role in wave mechanics and corresponds to the speed of a particle. The present book should be very useful to physicists and radio engineers and should give them a good basis for new discussions and applications.

Dieser Buchtitel ist Teil des Digitalisierungsprojekts Springer Book Archives mit Publikationen, die seit den Anfängen des Verlags von 1842 erschienen sind. Der Verlag stellt mit diesem Archiv Quellen für die historische wie auch die disziplingeschichtliche Forschung zur Verfügung, die jeweils im historischen Kontext betrachtet werden müssen. Dieser Titel erschien in der Zeit vor 1945 und wird daher in seiner zeittypischen politisch-ideologischen Ausrichtung vom Verlag nicht beworben.