Humboldt-Universität zu Berlin - Faculty of Mathematics and Natural Sciences - Experimental Particle Physics

Strong Force

The behaviour of the strong force (or strong interaction) is totally different from the forces we encounter in our every day life.  If two quarks are close together, the force is weak, however, this force increases drastically if they are separates in space.  Therefore, the strong interaction is often associated with a spring.  The strong interaction couples to the property of color-charge of a quark, which is additional to the quark's electric charge.  Since this color-charge occurs in three different states (red, blue and green) the intermediate particles, the gluons, carry this charge themselves leading to a self-coupling.  This is in contrast to photon exchange since photons carry no electrical charge.

Due to these properties of the strong interaction, quarks can not be observed on their own.  In processes of high energy physics, the energy mediated to quarks and gluons is so large that they can produce jets of many particles.  

Forces | Strong Force | Weak Force | Symmetry | Symmetry Breaking