Professor Riddle demonstrates the science learned from the events of 9/11.

http://www.youtube.com/watch?v=_NaAcAgQgoY

NIST Finds Global Collapse Of Twin Towers From Gravity Alone Is Unexplainable

Instead of trying to model the global collapse of two buildings through their greatest path of resistance at nearly free fall speeds via gravity alone, NIST simply surrendered the problem instead of relying on physics because it was too chaotic. The computer models were too complex apparently. In the field of structural engineering, nearly every problem has a solution except this one because of chaos.

However, physics will tell you that a item can not fall through other objects that provide resistance as if it were falling through air with zero resistance.