It is clear that the strong force is much stronger simply from the fact that the nuclear size (strong force dominant) is about 10 -15 m while the atom (electromagnetic force dominant) is about 10 -10 m in size. The body of data describing the strong force between nucleons is consistent with a strong force coupling constant of about 1: α s ≈ 1īut the standard model sees the strong force as arising from the forces between the constituent quarks, which is called the color force.įrom consideration of the ' particle in a box' problem and from just the uncertainty principle, we know it takes greater energy to confine a particle to a smaller volume. One of the discoveries about this force is that it dimishes inside the nucleons, so that the quarks are able to move freely within the hadrons. The implication for the strong force coupling constant is that it drops off at very small distances. Analysis of the coupling constant with quantum chromodynamics gives an expression for the diminishing coupling constant: Coupling constants for fundamental forces This phenomenon is called ' asymptotic freedom' because the quarks approach a state where they can move without resistance in the tiny volume of the hadron. The force isĪnother quantity with those dimensions which occurs naturally in the interaction of radiation with matter isĪ dimensionless constant which characterizes the electromagnetic force is The strength of the electromagnetic force can be related to the force between two electrons given by Coulomb's law. This coupling constant is also called the 'fine structure constant' since it shows up in the description of the fine structure of atomic spectra.

It appears naturally in the equations for many electromagnetic phenomena. Coupling constants for fundamental forces

Coupling constant mestrenova