The strong interaction happens between quarks and is responsible for holding hadrons together.

It has the gluon as its exchange particle.

The strong nuclear force is a residual effect of this interaction between nucleons in the nucleus.

Its exchange particle is the pion.

The range of the interaction is given by

$$ R = \frac{\hbar}{2mc} $$

for the ion with mass 135 MeV this works out to be 0.73 fm - very close to the range of the force preicted from the size of the nucleus.

Hideki Yukawa predicted the mass of the pion should be 100 MeV. The particle he predicted was discovered in 1947 in the upper atmosphere. This was the pion.

The interaction is responsible for the decay of quarks.

This is exactly what happens in beta decay.

$$ n \rightarrow p^+ + e^- + \bar{\nu_e} $$

$$ d^{-\frac{1}{3}} \rightarrow u^{+\frac{2}{3}} + e^- + \bar{\nu_e} $$

This is often called the change of flavour of quark.

The weak interaction has three exchange particles

$$ W^+, W^- \text{ and } Z^0 $$

These are very heavy and so short range.

The electromagnetic interation occurs as a result of the charges on particles.

The exchange particle id the photon.

As the photon is massless the range of the force is infinite.

Gravity is thought to be transmitted by gravitons.

It is only very recently that gravitational waves have been detected. First detection at LIGO in 2015.

The quantum theory of gravity has proved to be very difficult to understand and find experimental evidence for. it has led to many strange ideas including string theory and folded multi-dimensions.