  We investigate the internal structures of a Schwarzschild black hole by
solving the Wheeler-DeWitt equation. The generic bounded wave function has a
bouncing point around $r \simeq M$, where $M$ is the black hole mass. Due to
this quantum bouncing, there appears an ambiguity to define the arrow of time.
If we introduce two arrows of time, one can then interpret that two classical
spacetime is annihilated around the bouncing point. Finally, we provide a
conceptual explanation based on the generalized uncertainty principle.
