UMass Amherst study suggests primordial black holes could explode within 10 years

A team at the University of Massachusetts Amherst says there is a 90 percent chance that at least one primordial black hole could explode within the next decade, an event that could be observed by telescopes in space or on Earth and would not threaten life on Earth.

The scientists’ work centers on a class of black holes believed to form in the early universe, not from dying stars. Primordial black holes, or PBHs, are hypothesized to have formed within moments after the Big Bang when the cosmos was hot and dense. Unlike stellar-mass black holes, PBHs could span a wide range of sizes and masses, and some theories suggest they could contribute to dark matter. In theoretical terms, PBHs are expected to slowly emit radiation as they lose mass—a process known as Hawking radiation—until they eventually explode if they are small enough. While Hawking radiation has been discussed for decades, direct observation of an exploding PBH has remained elusive.

Researchers note that this explosive scenario would not be visible to the naked eye, but could appear as a sudden, high-energy event in data collected by telescopes designed to monitor gamma rays, X-rays, and other high-energy emissions. The new results build on the historical line of inquiry into PBHs, which were first proposed in the 1960s and 1970s by Soviet and British physicists, with Stephen Hawking later contributing to the theoretical framework that PBHs could evaporate and explode given the right conditions. In this context, the paper adds a provocative twist by suggesting explosions could be more common than previously thought if PBHs carry a tiny electric charge linked to a hypothetical “dark” sector.

The core idea, described as a dark-QED toy model, reexamines the assumption that primordial black holes are electrically neutral. According to co-author Michael Baker, an assistant professor of physics at UMass Amherst, the team explored what would happen if a PBH carried a small amount of dark electric charge. They argue that this could temporarily stabilize the hole before a final explosive release of energy. In their framing, the explosion frequency could rise from once every 100,000 years to roughly once every decade, bringing the prospect of a nearby exploding PBH within reach of current observational capabilities. Baker said, "We’re not claiming that it’s absolutely going to happen this decade, but there could be a 90 percent chance that it does." The researchers also note that the process would emit a spectrum of particles, including potential signals not yet observed in nature.

The study, published in Physical Review Letters, outlines what the authors describe as a plausible scenario in which current experiments could witness an exploding PBH. If confirmed, such an event would offer direct evidence for PBHs, a detection of Hawking radiation in action, and new insights into the fundamental particles that constitute the universe. The authors emphasize that catching such an explosion would require preparedness across observatories, as the signal could manifest across multiple wavelengths and particle channels.

This line of inquiry connects to a longer scientific thread about the origins and fate of black holes. PBHs would be much smaller and lighter than the supermassive black holes that reside at the centers of most galaxies, including our Milky Way. Their potential role in the dark matter puzzle has kept PBHs in the realm of intriguing, testable hypotheses rather than established facts. Hawking radiation predicts that lighter black holes emit more radiation and would heat up, accelerating their evaporation as they lose mass. In the PBH scenario, that radiation could become detectable as PBHs approach the end of their lifespans.

The authors argue that their dark–QED framework provides a way to reconcile observational constraints with the possibility of an explosive PBH within reach of modern instruments. They caution that the results are contingent on the validity of the model and the existence of a dark charge, but they also stress that the research should spur targeted searches for nearby PBHs and associated Hawking radiation signals. If such an explosion were observed, it would mark a watershed moment in physics, offering tangible evidence for PBHs and informing the particle content of the universe.

Historically, proposals about PBHs have evolved with advances in cosmology and high-energy physics. The early proposals credited Zeldovich and Novikov in the 1960s laid groundwork for considering PBHs as natural outcomes of early-universe conditions. Hawking’s 1971 work further framed the evaporation process that could lead to explosive endpoints for sufficiently small PBHs. The new study does not claim that PBH explosions will occur imminently, but it argues that a nearby event could be detectable with contemporary observational capabilities, prompting scientists to sharpen their search strategies and instrumentation to capture any forthcoming PBH explosions in real time.

In short, the Massachusetts team’s model suggests a non-negligible probability that a PBH could explode within the next decade, potentially within the observational sweet spot of existing telescopes. While the implications are profound for our understanding of black holes, Hawking radiation, and particle physics, researchers acknowledge that further data and independent verification will be required to confirm any exploding PBH and to interpret its signals. If borne out, the discovery would not only illuminate a fundamental aspect of black hole physics but also deepen humanity’s understanding of the universe’s earliest moments and the particles that comprise matter itself.