The biggest problem I see is that for any reasonable black hole masses, the evaporation rates are so short, you would never be able to get them to last long enough to use. The evaporation rate by the Hawking Process varies as the inverse third power of the black hole mass:
Mass Lifetime (grams) ----------------------------------- 10^33 (sun) 10^64 years 10^15 10^10 years 10^9 0.3 seconds 10^7 0.3 micro seconds 10^-5 10^-43 sec -------------------------------------
So, if you want to manufacture a mini black hole that lives longer than 1 microsecond, it will have to have a mass in excess of 10 million grams! To manufacture a black hole, you would have to compress a piece of matter to a size less than its Schwarzschild radius which is given as follows:
Mass radius Effective density --------------------------------------------------- 10^33 2.7 kilometers 5 x 10^16 gm/cc 10^15 2.7 x 10^-13 cm 5 x 10^52 gm/cc 10^9 2.7 x 10^-22 cm 5 x 10^64 gm/cc 10^7 2.7 x 10^-24 cm 5 x 10^70 gm/cc 10^-5 10^-33 cm 10^94 gm/cc --------------------------------------------------------
So, a 10 million gram mini black hole would be 10 billion times smaller than an atomic nucleus, and it would have to be manufactured by compressing a 1 gram object to a density some 10^70 times higher. It would then evaporate in less than a microsecond. I see this as a severe, if not fatal, technological challenge!
Copyright 1997 Dr. Sten Odenwald
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