The analysis of the behavioral trend of particle using Klein-Gordon and Dirac equation that was minimally coupled to electromagnetic wave four-vector potential has been carried out. In the analysis, it was clearly observed that each of them has non-relativistic limit at one stage or the other and based on this limitation, there is a great challenge posed on the idea of single particle interpretation since in each case there is a particle and an anti-particle. It therefore reveals the fact that there is no conceptually real existence of single particle in isolation when it comes to relativistic quantum mechanics for any of the equations being used to study the interaction of particle with electromagnetic field.
Analysis, charged particle, interaction, hehaviour, Electromagnetic field, Relativistic Quantummechanics, Couple. Potential.