Textbooks say that for a distant external observer, an infalling object never reaches the horizon because tends to 0 as approaches . But this conclusion assumes the object is a test particle with negligible mass. If we take the object's own mass seriously, then the exterior spacetime is determined by the total mass . The new horizon is at , so the old surface is no longer the true coordinate singularity. That means the object's radial velocity does NOT vanish at ; it only vanishes asymptotically at the new horizon . So the coordinate time needed for the object to cross the original surface is finite. My question: Does this show that the "eternal freezing" result is only valid for test particles, and that a finite massive object can indeed enter the original horizon within finite external time? Am I missing something?
Can a finite massive object enter the horizon in finite external coordinate time?
Henry


