Depends on what "low mass" means. An earth-mass black hole lasts 10^50 years. A black hole the mass of Mount Everest lasts 10^21 years.
Black holes on the order of metric tons would have evaporated by now. But primordial black holes can come in any size, and there is a vast range of them that will exist much longer than the universe has already existed.
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Depends on what "low mass" means. An earth-mass black hole lasts 10^50 years. A black hole the mass of Mount Everest lasts 10^21 years.
Black holes on the order of metric tons would have evaporated by now. But primordial black holes can come in any size, and there is a vast range of them that will exist much longer than the universe has already existed.