Elementary remarks about the time, mass and relativistic dynamics of quantum systems

One of the most important problems in elementary particle physics in the last century consists in the construction of a simple, well-defined theory that unites the ideas of quantum mechanics and relativity. The purpose of this brief paper is to make in-principle some personal and particular remarks on the fundamental concepts of mass and time and about some of their consequences on the relativistic dynamics of quantum systems. Key words: Particle physics, quantum systems, relativistic dynamics. (authors)