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Good Morning,

I have read the other posts on Hawking Radiation, and did not want to post a question to an older post... I just want a quick clarification of a point.

Can you please clarify is this is correct for me? "From reading the other posts, a BH loses mass, not because it is absorbing an anti-particle or a particle with a negative energy, it is losing mass because the energy to create the "real" particle pair from virtual particles takes some energy from the BH. When one escapes, it is taking 1/2 of this energy (more or less) from the BH."

Is my understanding correct?

As a follow up, how much energy is a solar mass BH losing per second doing this? Has anyone ever calculated how much energy a BH loses / second? or is this a ridiculous question?

Thanks

Rick
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    yes, the energy is taken from the black hole in order for virtual to become real. see here my analogy https://physics.stackexchange.com/q/451618/ – anna v Aug 14 '19 at 15:36
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    The virtual particle story of Hawking radiation is a simplification. Please see https://physics.stackexchange.com/a/252236/123208 You may enjoy playing with the Hawking radiation calculator. – PM 2Ring Aug 14 '19 at 15:36
  • FWIW, a 1 solar mass BH is a bit too small to form, the smallest are around 3 $M_\odot$. And the Hawking radiation temperature of such BHs is tiny, the CMB is much hotter, so they receive a lot more energy than they can radiate. – PM 2Ring Aug 14 '19 at 15:41
  • @PM2Ring - what would be the smallest BH that would be hotter than the CMB? – Rick Aug 14 '19 at 19:07
  • The Hawking radiation calculator can tell you that. Just plug in 2.725 K as the temperature. The answer is 0.00753950 Earth masses. – PM 2Ring Aug 14 '19 at 19:11
  • @PM2Ring - the question then becomes, if they are absorbing more from the CMB than they evaporate from Hawking Radiation, how does one evaporate at all? (Pardon my ignorance, I am not a scientist but an engineer.) – Rick Aug 14 '19 at 21:28
  • The CMB wiil be colder than stellar mass BHs in roughly $10^{29}$ years, and by then there won't be much starlight warming BHs either. That's a very long time, but it's an eyeblink in comparison to how long it will take for those BHs to fully evaporate. And of course the SMBHs will take even longer. – PM 2Ring Aug 15 '19 at 04:11

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