[steve_adams_86]

Well, I’ve exposed myself. I don’t have a PhD in physics. In fact, I don’t know much about physics. Including the things I comment about on Hacker News (my bad).

I’m not sure how I made it all these years thinking the radiation came from inside.

I see now that it’s hypothesized to be some crazy interplay of particles and antiparticles within vacuums in curved space time which leads to the black hole absorbing a lesser charged particle while the higher charged particle is emitted as radiation… Which incurs some sort of mass debt for the hole due to the rules of vacuums? I will have to read about it for a few years before it makes any sense. In the meantime I’ll avoid saying dumb things about it on the internet

[Maxatar]

You didn't say anything dumb whatsoever. Your explanation of it comes from Hawking himself but it was more for illustrative purposes rather than a rigorous description of it.

At any rate, even taking your description which certainly has merit, it is still not the case that the radiation comes from the inside of the black hole, from beyond the event horizon. Rather it's that just outside of the event horizon a virtual particle anti-particle pair is produced which has a combined energy of zero. One way their energies can add up to zero is for one to have positive energy and the other to have negative energy. The explanation then goes that the virtual particle with negative energy enters the black hole and the virtual particle with positive energy escapes, which results in the mass of the black hole decreasing. But both of these particles were formed outside of the black hole, not beyond the event horizon.

So yes the black hole loses mass, and yes for illustrative purposes one can think about a thought experiment involving the production of virtual particle anti-particles, but the key principle is that nothing escaped the black hole in the sense of coming from within the event horizon.

[Borg3]

Oh noes my friend.. Its not about negative energy, but background (void) temperature. The pair of particles (matter / anti-matter) spawn, cooling down the vacoom. Once they anihilate again, they change to energy (various photon emisions) increasing background temperature again. Thats why empty space is not at 0 kelvin. Every time such particle is absorbed by blackhole, it just increases it energy (and possibily mass). Not sure where that evaporation comes from ;)

[Maxatar]

There is no singular "it". I am responding to someone else who came to understand Hawking radiation through a thought experiment that Hawking himself described for pedagogical purposes.

A brief description of that thought experiment involving negative energy can be found here along with the appropriate citation coming from Hawking's "A Brief History of Time":

https://en.wikipedia.org/wiki/Negative_energy#Hawking_radiat...

>Virtual particles can exist for a short period. When a pair of such particles appears next to a black hole's event horizon, one of them may get drawn in. This rotates its Killing vector so that its energy becomes negative and the pair have no net energy. This allows them to become real and the positive particle escapes as Hawking radiation, while the negative-energy particle reduces the black hole's net energy. Thus, a black hole may slowly evaporate.