BUFFALO, N.Y. — When picturing the creation of a black hole, one might visualize a massive star collapsing under its own gravity. However, the tumultuous backdrop of the early universe allowed for the formation of much smaller black holes—primordial black holes (PBHs)—which may have emerged long before stars began to form. These enigmatic entities have been theorized for decades and are thought to potentially account for dark matter, the elusive substance that constitutes roughly 85% of the universe's mass.

Despite extensive hypotheses, no primordial black holes have been directly observed to date. A recent groundbreaking study led by the University at Buffalo encourages researchers to broaden their search strategies, positing that evidence of PBHs might be concealed within both vast cosmic structures and everyday objects on Earth.

The research, published in the December issue of Physics of the Dark Universe, explores the possibility that a primordial black hole trapped within a rocky body in space might consume its liquid core, resulting in a hollow structure. Additionally, it suggests that more agile PBHs could leave behind minute, detectable tunnels when passing through solid materials, including those right beneath our feet.

Co-author Dejan Stojkovic, a physicist at the University at Buffalo, emphasizes the importance of innovative approaches. "The chances of finding these signatures are small, but the resources required for the search are minimal. The potential reward—finding definitive proof of primordial black holes—could revolutionize our understanding of the universe. "

The researchers calculated the maximum size of a hollow object that could support itself without collapsing, concluding it must not exceed one-tenth the radius of Earth. This implies that if such hollow formations do exist, they are more likely to manifest as minor celestial bodies than as full-fledged planets.

The study delves into how PBHs might interact with various materials on Earth. For example, if a primordial black hole with a mass of 10^22 grams traversed a solid object, it could leave behind a tunnel barely 0.1 microns wide—a distortion undetectable by casual observation.

Stojkovic points out that while the odds of a PBH passing through any given object are extremely low—calculated as just 0.000001 for a billion-year-old rock—searching for signs of these passages in ancient materials could yield surprising insights.

Yet, concerns about safety are laid to rest. Even if a primordial black hole were to come into contact with a human, Stojkovic assures, the encounter would not be catastrophic. "The key factor is the PBH's velocity. If it travels faster than the speed of sound in a medium, it would essentially leave a hole without causing significant damage, similar to a bullet passing through glass. "

Amidst this intriguing pursuit, the scientific community recognizes a critical gap in theoretical frameworks. Stojkovic highlights a need for fresh perspectives, as conventional models of physics—including quantum mechanics and general relativity—have remained largely unsolved for over a century. He reflects, "Even the brightest minds have struggled with these questions for decades. We must explore novel frameworks to unlock these cosmic mysteries. "

As the quest for primordial black holes continues, the hunt might take scientists from the far reaches of space into our backyards and beyond, challenging our understanding of the universe we inhabit. Will we be the ones to finally fathom the depths of dark matter and discover the lurking shadows of primordial black holes? The search is on!