Date: 18/07/2017 17:14:27
From: Cymek
ID: 1091576
Subject: Virtual particles and black holes

In regards to the below, if one of the particles becomes “real”, is it mass evaporating from the black hole or is the particle just not being cancelled out because its pair has been pulled into the black hole.

Other predictions are harder to verify. Vacuum fluctuations are always created as particle–antiparticle pairs. The creation of these virtual particles near the event horizon of a black hole has been hypothesized by physicist Stephen Hawking to be a mechanism for the eventual “evaporation” of black holes. If one of the pair is pulled into the black hole before this, then the other particle becomes “real” and energy/mass is essentially radiated into space from the black hole. This loss is cumulative and could result in the black hole’s disappearance over time. The time required is dependent on the mass of the black hole (the equations indicate that the smaller the black hole, the more rapidly it evaporates) but could be on the order of 10 to the 100 years for large solar-mass black holes.[6

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Date: 18/07/2017 19:32:37
From: Bubblecar
ID: 1091632
Subject: re: Virtual particles and black holes

From Wikipedia:

Physical insight into the process may be gained by imagining that particle–antiparticle radiation is emitted from just beyond the event horizon. This radiation does not come directly from the black hole itself, but rather is a result of virtual particles being “boosted” by the black hole’s gravitation into becoming real particles. As the particle–antiparticle pair was produced by the black hole’s gravitational energy, the escape of one of the particles lowers the mass of the black hole.

An alternative view of the process is that vacuum fluctuations cause a particle–antiparticle pair to appear close to the event horizon of a black hole. One of the pair falls into the black hole while the other escapes. In order to preserve total energy, the particle that fell into the black hole must have had a negative energy (with respect to an observer far away from the black hole). This causes the black hole to lose mass, and, to an outside observer, it would appear that the black hole has just emitted a particle. In another model, the process is a quantum tunnelling effect, whereby particle–antiparticle pairs will form from the vacuum, and one will tunnel outside the event horizon.

https://en.wikipedia.org/wiki/Hawking_radiation

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