Spacetime is not a flat 2D net underneath the planet. The 3D metric lattice permeates directly through the planet's interior, curving smoothly to maximum density and time-dilation at the core.
Couples relativistic energy density ($E/c^2$) and local metric acceleration ($g$) with information-geometric resonance ($\mu$).
Unlike the 2D funnel myth, the grid inside a planet follows a smooth harmonic parabola ($r^2$), preventing a singularity at $r=0$.
Anything travelling through the invisible 3D lattice must follow the local connection coefficients ($\Gamma^\mu_{\alpha\beta}$) of the grid.