An application of semigroup theory to a fragmentation equation

The process of fragmentation arises in many physical situations, including polymer degradation, droplet breakage and rock crushing and grinding. Under suitable assumptions, the evolution of the size distribution c(x, t), where x represents particle size and t is time, may be described by the linear integro-differential equation

Investigation of the basic foundations of masers and lasers

Research work on the theory of lasers and masers is reported. Special attention is given to technological applications of laser theory

Image formation in microwave holography

Microwave holograms are made without offset reference beam, but it has been found that Van der Lugt filter can be used to produce image offset. Also, filter permits "decoding" of holograms in contrast with usual practice of reconstructing visible-light analogs of original micro-wave wave fronts

Masar Amplication of Incoherent Radiation by Interstellar OH

Molecular excitation model for maser amplification of emission lines of interstellar hydroxyl radica

Bifurcation Analysis of a Stochastically Driven Limit Cycle

We establish the existence of a bifurcation from an attractive random equilibrium to shear-induced chaos for a stochastically driven limit cycle, indicated by a change of sign of the first Lyapunov exponent. This addresses an open problem posed by Kevin Lin and Lai-Sang Young, extending results by Qiudong Wang and Lai-Sang Young on periodically kicked limit cycles to the stochastic context

The photoelectric effect without photons

Mathematical model of photoelectric effect without photon

Microwave holography for nondestructive testing

Holographic methods permit use of very large effective apertures so that weak signals can be collected over wide area and integrated to form image. Technique, modification of side-looking radar principle, can be used at very short ranges needed for nondestructive inspection of test specimens

Theory of collision effects on line shapes using a quantum mechanical description of the atomic center of mass motion - Application to lasers

Quantum mechanical treatment of atomic center of mass motion in theory of collision effects on line shape

Stability for a class of equilibrium solutions to the coagulation-fragmentation equation

We consider the behaviour of solutions to the continuous constant-rate coagulation-fragmentation equation in the vicinity of an equilibrium solution. Semigroup methods are used to show that the governing linear equation for a perturbation epsilon(x,t) has a unique globally defined solution for suitable initial conditions. In addition, Laplace transforms and the method of characteristics lead to an explicit formula for epsilon. The long-term behavior of epsilon is also discussed