# Fine structure parameter $\alpha$ at event horizon

As magnetic field lines collect at a black hole event horizont (for no field lines will be present in the black hole) then ratio of electric field to magnetic field will change, so by this change in magnetic/electric ratio can we re-calculate the potency of alpha the fine structure parameter near the event horizon?

• Why do you think that 'no field lines will be present in the black hole'? What 'ratio of electric field to magnetic field' are you talking about? – user23660 Nov 20 '13 at 14:57

The fine-structure constant is not determined by magnetic and electric field strengths, but by other universal constants: $$\alpha=\frac{e^2}{\hbar c}$$ (using cgs here because I'm an astrophysicist). This has a value1 of $\sim1/137$.
1 - There is some debate as to whether $\alpha$ is indeed a constant; some of claimed variations over large epochs (Gyr time scales) on the order of $\Delta\alpha/\alpha\sim10^{-6}$