# Is the minimum mass of a black hole the planck mass?

Leonard Susskind said "It's thought to be the mass of the smallest black hole that can form" (or something like that when referring to the planck mass in his string theory lectures) and I've always been told that the planck mass is the mass of the least massive possible micro-black without ever researching whether or not it was true. I just came across a paper http://cds.cern.ch/record/519241/files/0109057.pdf (Sec. 1, eq. 7) that says, unless I'm drastically misinterpreting it, that the minimum mass of a black hole is $10^{12}$ kg. Is this the lower limit in the Standard Model? Did the lower limit of 1 planck mass come from string theory or loop wquantum gravity? Or does it just not exist?

• I can't answer your specific question, but any statement regarding the Planck scale necessarily depends on a theory of quantum gravity, and we haven't decided on one yet. IOW, according to some theories it might be, but we don't know if those theories are correct. – Javier Nov 26 '16 at 4:02
• This question was attacked by the following paper: arxiv.org/abs/gr-qc/0609055 – riemannium Oct 15 '18 at 14:49