How does Hawking Radiation work?


[Hawking Radiation]( is a is radiation that is predicted to be produced by black holes. Anti-particle- and particle-pairs spontaneously appear close to the event horizon of the black hole. If the anti-particle falls into the black hole, while the corresponding particle can escape, a particle inside the black hole will be annihilated an “radiated away” by the escaping particle.

My question is: why is it only the anti-particle that falls into the black hole? Shouldn’t the particle have an equal probability of falling into the black hole, keeping the whole system at an equilibrium?

In: Physics

Yes, Hawking radiation emits equal amounts of matter and anti-matter on average. However, most of the radiation is in the form of photons and gravitons, which are their own anti-particles.

It is dependent on the current net charge of the black hole. The opposite charge will fall in, the like charge will repel, whichever it may be

As an aside, the whole particle-antiparticle picture is rather iffy, and Hawking himself used the analogy with a clear warning to not extrapolate on it because it was technically inaccurate.

In reality, quantum fields do all kinds of things, and only some of them can be fully described as being a particle. However, the math gets very hairy, and the math for simple particle interaction is simpler, so we do the inverse – instead of modeling the particle as being an oscillation as a field, we break apart the things the field is doing into particle-like components. This makes the math easier, but it means we introduce a bunch of fake particles that don’t really exist.

What’s going on at the black hole is that, because of differences in the structure of spacetime, what looks there to be a perfectly normal quantum field looks here like a thermal bath of particles heading away from the black hole. The particle-antiparticle picture is just a way to make sense of how the normal vacuum field structure ends up generating particles, but in reality the simplest explanation is just that the things the field normally does look like (and ultimately are) particles when viewed from a different frame of reference.