Charged Black Holes and the Density Cap: Where the Inner Horizon Meets the Capped Core

The capped radius is 7.876e-10 metres. At half the extremal charge the inner horizon already sits at 1.978e+03 metres, far outside the cap, and the two structures meet only at a charge fraction of 3.264e-07, extremely close to uncharged. The extremal charge itself is 1.714e+21 coulombs. In other words, for any appreciable charge the inner horizon encloses the capped core with room to spare, and the cap modifies only the deep interior inside the Cauchy horizon. Astrophysical charge is expected to be tiny, so the near-zero meeting fraction might look like a curiosity. Computed from stated assumptions, not measured.