The Ghosts of Departed Quantities
Keith Carlock
Invisibility Suits, Portals, Magic Ghost Number Cubes and Other Mathematical Ideas [ also, ideas towards an amended Invisible/Holographic Principle]
Only the tell-tale signs of the holodeck chamber and APRO inside, gives away, visually, what is the real and the virtual worlds. And the only way one can tell if another is real is when they pass thru each other's apparent bodies like ghosts.