Sometimes due to specific combinations of properties extended objects behave as point-like even in their immediate vicinity. For example, spherical objects interacting in 3-dimensional space in a particular manner called the inverse square law behave in such a way as if all their matter were concentrated in the geometric centers of their spherical shapes. In Newtonian gravitation and classical electromagnetism, for example, the respective fields outside of a spherical object are identical to those of a point particle of equal charge/mass located at the center of the sphere.
In particle physics, whose theoretical framework is quantum field theory, "point particle" is synonymous with "elementary particle", which is defined as a particle without structure or, equivalently, as a particle lacking component parts. According to the Standard Model (of fundamental particles and forces), quarks, leptons and the vector bosons are point particles in this sense.
Photon emission mechanism for the hydrogen atom from a new, non-Copenhagen interpretation of the electron wave functions.(Report)
Mar 13, 2012; I. INTRODUCTION In a previous paper by the author, (1) Schrodinger's wave equation for the electron was solved for the case of a...