A model calculation of the value of the electromagnetic coupling constant at $q^2=m_Z^2$

A QCD model with an infinite number of vector mesons suggested by one of the authors is used to derive the value of the correction $\delta {\alpha }_{hadr}$ for $\alpha (m_Z^2)$ due to the strong interactions. The result is $\delta {\alpha }_{hadr}=0.0275(2)$ ; thus $\alpha(m^{2}_{Z}) = (128.96(3))^{-1}$.