Some researchers believe the smallest black holes, formed in the chaotic infancy of the universe, may be hiding in plain sight—embedded in planets or even leaving microscopic tunnels in everyday materials here on Earth. According to a new study from the University at Buffalo, these primordial black holes could range from forming hollow planetoids in space to punching through rocks and metals with tunnels detectable under a microscope. While the chances of finding these elusive remnants are slim, the researchers argue it's worth sifting through ancient materials, as the payoff could rewrite what we know about dark matter and the universe. So, next time you see an old rock or a creaky building, could you be near the marks of a cosmic intruder?
What would you examine first if you wanted to hunt for primordial black holes?