Not really. Not unless you manufactured them yourself, or that the Earth somehow managed to sweep up a bunch of them. We know that has not happened, because if even a single microscopic black hole had lodged itself in the earth, it would have consumed the entire planet in a few million years as it moved back and forth like a pendulum, eating any atoms it encountered along the way.
Black holes can, theoretically, come in any size. The most popular sizes we definitely know about are the 'stellar-mass' and 'supermassive' types. Some cosmologists have speculated that soon after the Big Bang, black holes with masses from 0.00001 grams all the way up to stellar, or even supermassive sizes could have been created. But because black holes evaporate at a rate that depends on the third power of their mass, any black hole with a mass less than about 1000 trillion grams would have already evaporated by today, some 15 billion years after the Big Bang. That means there could be lots of mini black holes with masses greater than 1000 trillion grams, but less than stellar-massed running around in the universe today. Depending on just how numerous the small ones are, some of them, perhaps one or two, could have been swept-up by the Earth, and may now be inconspicuously lodged deep in the Earth's interior. No one expects, however, that they would be on the surface of the earth. By the way, a black hole with a mass of 1000 trillion grams would have a size of about 10^-12 centimeters or slightly larger than the size of a large atomic nucleus! Good luck finding one of these. It would also be spewing out lots of lethal x-rays; perhaps a good way to find one. Just look for a 'radioactive' atom with the inertia of Mount Everest!
No one seriously thinks that it would be technologically possible to manufacture small black holes. You would have to focus the energy of a hydrogen bomb into a carefully designed blast wave to compress a few micro grams of matter into a black hole state. It would then promptly begin to evaporate!
Copyright 1997 Dr. Sten Odenwald
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