Small Black Holes The smallest possible black hole is about m across—the so-called Planck length. Smaller structures get wiped out by quantum fluctuations. The creation of even the smallest black hole would require energies of around GeV, which is billions of times larger than RHIC energies. And even if it could create such an object, the black hole would evaporate on a timescale of s. There are certainly more pressing things to worry about.
