# Which is the physical interpretation of the “strange” constant $e \cdot c/ 4 \pi$?

This constant is assignable to charged leptons $$(e, \mu, \tau)$$ representing the fraction of their individual magneton $$\hat{m}= e \cdot \hbar/ 2 m$$ to their Compton-wavelength $$\lambda_{C} = h / m c$$: $$\begin{eqnarray*} \frac{\hat{m}}{\lambda_{C}} = e \cdot c / 4 \pi [\frac{A}{m} \cdot m^{2}] \end{eqnarray*}$$
Its dimensionality indicates that it determines a natural constant of magnetic flux: $$4,8 \times 10^{-18}$$ [Wb], however only a fraction $$4 \alpha$$ of the magnetic flux-quantum $$\Phi_{0} = h/ 2e$$. The constant may thus define magnetic flux in a leptons dipole-field.

• This does not seem to be a question about history, you should ask on Physics SE. – Conifold Mar 20 at 22:29
• As a physicist, I can confidently state that it's just another wacky fudge factor. <-- which happens to correctly predict real world behavior. – Carl Witthoft Mar 21 at 12:31
• A question like this is really in need of one or more published sources to give it a credible context. – terry-s Apr 8 at 13:37