Related to my other misguided question, D-branes are equivalent to p-branes. D-branes are described by a sheet in topologically trivial spacetime. p-branes are extremal black branes. They have an event horizon which is infinitely far away along spatial geodesics. However, we may cross the event horizon in a finite affine time for null and timelike geodesics. So, we need to extend spacetime, and if we do that, the Penrose diagram consists of an infinite chain of universes, ordered by time. Each universe has its own null infinity. Causal information is "created" in the past null infinity of each universe. So, a universe in the "future" contains information which is causally independent from and inaccessible to "our universe". All this is invisible if we work with D-branes. Where did all the other universes go to? Where is all the information contained within them encoded?