Fundamental interaction

A fundamental interaction or fundamental force is a mechanism by which particles interact with each other, and which cannot be explained in terms of another interaction. Every observed physical phenomenon can be explained by these interactions. The apparent irreducible nature of these interactions leads physicists to study the properties of these forces in great detail. In modern physics, there are four fundamental interactions (forces): gravitation, electromagnetism, the weak interaction, and the strong interaction. Their magnitude and behavior vary greatly, as described in the table below.

The modern quantum mechanical view of the three fundamental forces (all except gravity) is that particles of matter (fermions) do not directly interact with each other, but rather carry a charge, and exchange virtual particles (gauge bosons), which are the interaction carriers or force mediators. For example, photons are the mediators of the interaction of electric charges; and gluons are the mediators of the interaction of color charges.