Weak nuclear force is not really a “force.” Weak nuclear “force” facilitates transformations between the first column and the second column of quarks, and the first column and the second column of leptons as shown in the fermion table below.
What this means is that only left-handed fermions experience the weak nuclear force.
All particles in the table below have spin=1/2. The elementary particles with spin=1/2 are known as fermions. This is why the table below is also known as the fermion table.
In the fermion table below the “L” signifies left-handed and “R” right-handed chirality.
: electron type neutrino
: muon type neutrino
: tau type neutrino