We use the full quantum treatment to study formation of a black
hole as seen by an asymptotic observer. Using the Wheeler-de Witt
equation to describe a collapsing shell of matter (a spherical
domain wall), we show that the black hole takes an infinite time to
form in the quantum theory, just as in the classical treatment.
Asymptotic observers will therefore see a compact object but never
see effects associated with an event horizon. To explore what
signals such an observer would see we study radiation of quantum
fields in this background using two approaches: functional
Schroedinger method and an adaptation of Hawking's original
calculation. The radiation is not exactly thermal, the thermal
distribution being superposed with some non-thermal features. We
discuss the conjecture based on our analysis that a collapsing shell
of matter will evaporate completely by non-thermal radiation and
never form a black hole. In this case, gravitational collapse
preserves unitarity and our findings may resolve the black hole
information loss problem. One might separate the Hilbert space into
super-selection sectors: in those with no initial black holes,
evolution will be unitary.