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Astrophysics/penrose process


Dear Mr. Nelson

I just found that penrose process which is extracting energy from black hole. By the way i just confused, some person said that penrose process decrease the angular momentum of black hole and also decrease the mass of black hole, but another person said it's decrease the angular momentum of black hole BUT increase the mass of black hole.

Thank you so much


Angular momentum is related to rotational energy.  If net energy is escaping, then the mass/energy equivalent of the black hole is decreasing...but the static mass may increase.  It depends on the exact kinematics.  But the total mass/energy of the black hole would decrease.


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Dr. Stephen O. Nelson


Fusion, solar flares, cosmic rays, radiation in space, and stellar physics questions. Generally, nuclear-related astrophysics, but I can usually point you in the right direction if it's not nuclear-related or if it's nuclear but not astrophysics.


Just moved from being a physics professor at the University of Texas of the Permian Basin into government work. Doctoral dissertation was on a reaction in CNO-cycle fusion, worked in gamma-ray astronomy in the space science division of the naval research laboratory in the high-energy space environment branch.

Government work as a physical scientist with a nuclear focus.

Ph.D. in physics, research was on nuclear fusion reactions important in stellar fusion, further work on space telescope technology.

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