DO Tan Si
HoChiMinh-city Physical Association, Vietnam
Title: Fourier transforms of geometric forms and interference patterns, deflection of light by the sun
Biography
Biography: DO Tan Si
Abstract
Consider an object defined by a function equal to unity for a point inside a domain D and to zero for a point outside. Consider the diffraction of a plane wave by this object. The diffracted wave may be described by the function . The probability for finding a plane wave in the diffracted wave is proportional to the square of the integral over the whole space of , i.e., the Fourier transform of calculated for . The problem of calculating the amplitude of diffraction and interference patterns is thus reduced to that of calculating the Fourier transforms of geometric forms. The aim of this work is to popularize the method for performing these calculations which is based on the properties of the Dirac delta and the Heaviside functions, the reciprocal vectors as explained in the previous work “On amplitude of Fraunhofer diffraction of waves by 3D objects”. Results of calculations for the cases of a point, an array of points, an array of stripes, discs, array of spheres and ellipsoids, cones, cylinders, intersections of them are given, completing the results obtained in the previous work. An attempt to calculate the angles of deflection of light by the form of the sun is also done and perhaps shows that the deflection given by General relativity is the sum of those by the form and the mass of the sun?