Gravity as falling space: the exterior equivalence principle, a speed limit for space, and a hypothesis under which collapse forms no horizon

The equivalence principle is normally applied from inside a rocket: no local
experiment within it can distinguish acceleration from gravity. Einstein’s own
derivations, however, used an outside view, in which the rocket moves through
space, a premise never stated as part of the principle. Extending the correspon-
dence to that outside view, the exterior equivalence principle, reveals a mismatch:
an accelerating floor moves to meet downward light, but a floor held static in
gravity does not. We propose that gravity is falling space, Acceleration Field
Space (AFS), a physical flow added to the metric of general relativity (GR) that
moves past static bodies at the local escape velocity. The Lorentz factor of a
static body in this inflow is the Schwarzschild coefficient, giving gravitational
time dilation, radial length contraction and mass–energy. For one body AFS is
the Gullstrand–Painlev´e form of the Schwarzschild metric, so it reproduces the
four classical tests exactly. The departure is one hypothesis additional to GR:
that the flow is real, so that moving through space and space moving past are
one relative motion. The speed limit c then applies to the flow relative to any
bounded source, so no sphere is trapped, no horizon forms, and a compact object
must have a surface outside 2GM/c^2. The exterior and the prompt ringdown
are unchanged, but the surface returns echoes, re-radiates the energy of accreted
matter and has a non-zero tidal deformability; current data allow only a surface
extremely close to 2GM/c^2. A sketched velocity-dependent source law keeps the
flow below c for any density; its dynamical completion is left open