| MadSci Network: Astronomy |
Theories 1 and 2 are basically correct, and for that matter so is the conclusion in your combination, though I don't think that conclusion follows quite so directly.
In quantum field theory (QFT), the vacuum itself has non-zero energy, and as such virtual particles are created and destroyed all of the time (at least, that's the theory, though there is considerable indirect evidence for this phenomemon). These particles are "virtual" because they cannot be directly observed as physical entities - to do so would violate laws such as conservation of energy, etc. However, it is thought possible that spacetime effects in General Relativity can make these particles "real", in which case they show up as radiation of one kind or another. One example is Hawking radiation which occurs at the event horizon of a black hole. It is also theorized that changing spacetime geometry can also give rise to particles coming out of the vacuum. The case you describe is just such a scenario.
[Also, an object falling into a black hole will generate gravitational waves that will carry energy away from the system.]
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