Since we have never seen a black hole up close and personal, we don't know for certain. However, the same caliber of physicists that predicted they should exist in the first place not believe that through a quantum tunneling process, black holes can emit particles very slowly over time if they are big black holes like the Sun, or emit particles explosively if they are microscopic black holes.
Stephen Hawking predicted black hole evaporation back in 1975. This theoretical possibility has now joined the ranks of the other bizarre features of these truly weird objects. Because the physical vacuum is not empty, the virtual particles that exist in it can become the unwitting source of particles for black hole evaporation. As the pairs form and disappear near a black hole, the tremendous tidal gravitational forces rip them apart, sending one member of the pair into the hole, and allowing the other to escape. From the outside, this looks exactly like a black hole evaporating and losing mass.
Copyright 1997 Dr. Sten Odenwald
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