  In the path integral approach, one has to sum over all histories that start
from the same initial condition in order to obtain the final condition as a
superposition of histories. Applying this into black hole dynamics, we consider
stable and unstable stationary bubbles as a reasonable and regular initial
condition. We find examples where the bubble can either form a black hole or
tunnel toward a trivial geometry, i.e., with no singularity nor event horizon.
We investigate the dynamics and tunneling channels of true vacuum bubbles for
various tensions. In particular, in line with the idea of superposition of
geometries, we build a classically stable stationary thin-shell solution in a
Minkowski background where its fate is probabilistically given by
non-perturbative effects. Since there exists a tunneling channel toward a
trivial geometry in the entire path integral, the entire information is encoded
in the wave function. This demonstrates that the unitarity is preserved and
there is no loss of information when viewed from the entire wave function of
the universe, whereas a semi-classical observer, who can see only a definitive
geometry, would find an effective loss of information. This may provide a
resolution to the information loss dilemma.
