2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/228309A new version of the geometry inside a black hole is proposed, on the grounds of an idea given by Doran et al. The spacetime is still time dependent and is a solution of Einstein's equations with a stress tensor corresponding to an anisotropic fluid. The energy density of the fluid is proportional to $1/t^{2}$ as in many dark energy models and the Brown-York quasilocal energy of the black hole interior equals its mass $m$.6 pages,one reference added, minor changes, no figuresHigh Energy Physics - TheoryAstrophysicstext