  Black holes are presumed to have an ideal ability to absorb and keep matter.
Whatever comes close to the event horizon, a boundary separating the inside
region of a black hole from the outside world, inevitably goes in and remains
inside forever. This work shows, however, that quantum corrections make
possible a surprising process, reflection: a particle can bounce back from the
event horizon. For low energy particles this process is efficient, black holes
behave not as holes, but as mirrors, which changes our perception of their
physical nature. Possible ways for observations of the reflection and its
relation to the Hawking radiation process are outlined.
