A Smooth Quartic-Core Regular Black Hole: Exact Static Solution, Effective NED Source, and a Validation Program

A new regular black hole called the Sharipov Smooth Quartic-Core. There is no singularity. The center is smooth, curvature is finite, and the metric is analytic at the origin. Far away it looks like Schwarzschild, near the center like de Sitter. I found an exact static solution and an explicit nonlinear electrodynamics source. I checked the horizons, photon orbits, and central curvature numerically. Some things are still open, including the Maxwell limit, hyperbolicity inside a certain radius, two-invariant fixes, rotation, and stability. The singularity is gone, and that does not depend on the source. The rest is honest work in progress. Keywords: regular black hole, nonlinear electrodynamics, smooth core, exact solution, no singularity.