All forces between objects are due to interactions .
All particle decays are due to interactions.
Electromagnetic interactions, responsible for electric and magnetic forces. Weak interactions, responsible for the instability of all but the least massive fundamental particles in any class. The Standard Model of particle physics is the relativistic quantum field theory of these the strong, electromagnetic, and weak interactions. In such theories, each type of interaction has a characteristic set of force carrier particles associated with quantum excitation of the force field related to that interaction. The carrier particles either appear in intermediate stages or are produced during all particle processes involving that type of interaction.