I think the charge neutrality doesn't pose a problem on this level. Imagine a (+e,-e)-pair is created. One of these particles, let's say -e, falls to an initially charge neutral hole. Then the charge of the hole is -e. When the next pair is created, the probability of the event where +e is pulled in and e- is pushed away is considerably higher than the probability of the event with opposite signs. The reason for this is the electrical force between the hole and the particles. If the next particle sucked in is also -e, then the asymmetry will be even more pronounced and after a few particle-antiparticle pairs the hole will return to the charge neutral state.
The reduction in the black hole mass as a result of the above process is analogous to the voltage of a spherical capacitor, whose radius increases. I bet many slashdot readers know a lot about capacitors. Inside a spherical conductor shell, there's a charged conductor sphere, which creates a Coulomb potential V(x) around itself. The voltage between the shell and the sphere is U = V(d)-V(r), where d is the distance of the shell from the center of the sphere and r is the radius of the sphere. The capacitance is proportional to dr/(d-r). Now let us increase d to infinity. Since charge is conserved, the difference of final and initial voltages is r/(d0-r) times the initial voltage, where d0 is the distance d in the initial state.
The analogy to the black holes replaces charge conservation with energy conservation and voltage with gravitation field. The energy stored by the electric field is analogous to the energy stored by the gravitation. This energy gain of the gravitation field is compensated from the mass of the black hole, at least if it is not rotating etc. Now if one estimates d0 for instance with an electron de Broglie wave length and r with a Schwartzschild radius of an object with mass m, one can estimate how much the mass of the black hole is reduced in a single Hawking radiation event. If we know the frequencies of these radiation events and of the events where ordinary matter falls to the hole, we get a balance equation, which tells exactly when the black holes grow or shrink. If no ordinary matter goes in, they'll just shrink.
So my point is that we don't need quantum foams, multiple universes, flying saucers etc. to convince ourselves that the particle colliders are safe and we want more of them. The exotic theories are needed only at the microscopic level and for this purpose we should be interested to have even more powerful colliders than LHC.
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I think the charge neutrality doesn't pose a problem on this level. Imagine a (+e,-e)-pair is created. One of these particles, let's say -e, falls to an initially charge neutral hole. Then the charge of the hole is -e. When the next pair is created, the probability of the event where +e is pulled in and e- is pushed away is considerably higher than the probability of the event with opposite signs. The reason for this is the electrical force between the hole and the particles. If the next particle sucked in is also -e, then the asymmetry will be even more pronounced and after a few particle-antiparticle pairs the hole will return to the charge neutral state.
The reduction in the black hole mass as a result of the above process is analogous to the voltage of a spherical capacitor, whose radius increases. I bet many slashdot readers know a lot about capacitors. Inside a spherical conductor shell, there's a charged conductor sphere, which creates a Coulomb potential V(x) around itself. The voltage between the shell and the sphere is U = V(d)-V(r), where d is the distance of the shell from the center of the sphere and r is the radius of the sphere. The capacitance is proportional to dr/(d-r). Now let us increase d to infinity. Since charge is conserved, the difference of final and initial voltages is r/(d0-r) times the initial voltage, where d0 is the distance d in the initial state.
The analogy to the black holes replaces charge conservation with energy conservation and voltage with gravitation field. The energy stored by the electric field is analogous to the energy stored by the gravitation. This energy gain of the gravitation field is compensated from the mass of the black hole, at least if it is not rotating etc. Now if one estimates d0 for instance with an electron de Broglie wave length and r with a Schwartzschild radius of an object with mass m, one can estimate how much the mass of the black hole is reduced in a single Hawking radiation event. If we know the frequencies of these radiation events and of the events where ordinary matter falls to the hole, we get a balance equation, which tells exactly when the black holes grow or shrink. If no ordinary matter goes in, they'll just shrink.
So my point is that we don't need quantum foams, multiple universes, flying saucers etc. to convince ourselves that the particle colliders are safe and we want more of them. The exotic theories are needed only at the microscopic level and for this purpose we should be interested to have even more powerful colliders than LHC.