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The standard explanation of Hawking radiation says due to vacuum fluctuations near to event horizon of a black hole, a pair of virtual particles are created, one (with negative energy) falls to the black hole (which reduces the energy/mass of the BH), and the other (with positive energy) escapes from the gravity of the BH as an electromagnetic wave (thermal radiation). (to be honest, I do not comprehend what a virtual particle is and what the negative energy means). However, I have two questions:

1- Why only the particle with the negative energy is pulled in to the BH and not the other.

2- The particle with positive energy escapes the BH gravitational field as an electromagnetic wave, which travels at the speed of light. Where does the energy come from?

Could someone explain these without analogy?

Thank you

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  • $\begingroup$ I don't believe "negative energy" has been accepted into scientific terminology (possibly because of some conflict with terminology in the singularity theorems), but I think the term is used to describe gravity in pop-sci contexts. "Virtual" particles might perhaps be described as "potential" particles in a particulate field, although "potential" is a term so general that it's often avoided. $\endgroup$
    – Edouard
    Oct 4 at 17:07
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    $\begingroup$ For the benefit of viewers who aren't native speakers of English, "scapes" is an archaic (very old) alternative to "escapes". $\endgroup$
    – Edouard
    Oct 4 at 17:15
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    $\begingroup$ @Edouard I, myself, am not a native English speaker. Thanks for the comment. Corrected. $\endgroup$
    – Ebi
    Oct 4 at 17:24
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    $\begingroup$ Have a look at my answer here, maybe it is simple enough physics.stackexchange.com/questions/90202/… $\endgroup$
    – anna v
    Oct 4 at 17:27
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    $\begingroup$ Hi Ebi. This has been asked before, and a group of got together to try and write a definitive answer. I've linked the previous question. $\endgroup$ Oct 4 at 17:29