Scientists are now directing their efforts towards an ancient Roman shipwreck off the coast of Sardinia. That lead, which was recovered from this site, is proving invaluable in the quest to understand dark matter. Found in 1988, this 2,000-year-old wreck continues to fascinate archaeologists. There are no physicists keener to study it than Ettore Fiorini of Italy’s Institute for Nuclear Physics (INFN). The ancient lead has rare properties that make it uniquely valuable for the most sensitive physics experiments. These experiments are designed to look for rare, difficult-to-detect events, including those caused by dark matter.
The lead from history has the great advantage that it has lost the radioactivity which complicates observations in experiments. This decay process must be done over the course of hundreds of years. Consequently, the lead from this shipwreck is just what’s needed for shielding experiments trying to detect ghostly particles believed to make up most of the universe’s mass.
The Role of Ancient Lead in Modern Experiments
Ettore Fiorini, the principal investigator, has enthused about using some of the ancient lead to build shields for his experiments. To stop the particles coming from the cavern, he said, “I have to construct a lead shield.” He noted a significant challenge: “The shield itself generates other particles that disturb the experiment.” His research on the CUORE experiment is of great sensitivity. Its survival hinges on having a place without any type of disturbance—especially those created by the presence of people.
CUORE, an experiment to observe one of the rarest interactions in particle physics—the decay of a proton—needs a very clean environment to succeed. Extreme sensitivity is required for these sorts of experiments, noted Dr. Paolo Gorla, who works alongside Fiorini. He concluded, “The mere presence of a human or the earthiness of the rock in the mountain itself can affect the experiment. This level of sensitivity means that even small disturbances might threaten the robustness of the results.
Dr. Maria Perez-Alvaro sparked a debate within the scientific community regarding the implications of using such materials in modern research. She warns that if the new finds are not archaeologically documented, vital clues to their origins and significance will be lost forever.
“Everything that is taken out of the water without a proper archaeological record, we will never have that information back.” – Dr. Maria Perez-Alvaro
Dr. Perez-Alvaro is well aware of the added value of working with such ancient materials. As he says, first they need to be accurately recorded and reclaimed. She wrapped up with a call to consider what is practical. As Junker put it, “Having 1,000 military-style ingots sitting in a museum’s back closet is not necessarily helpful. Her point of view underscores the conflict between protecting cultural identity and pursuing scientific research.
Dark Matter: The Universe’s Great Mystery
Dark matter is one of the most important and elusive mysteries that astrophysicists seek to solve. It’s believed to account for close to 85 percent of the universe’s total mass. The term “dark matter” was first used by Swiss-American astronomer Fritz Zwicky, who called it “dunkle materie.” Its mysterious nature, its composition, and the understanding of its properties could give us fundamental clues as to the origin and evolution of the universe.
Dr. Theresa Fruth is one of many scientists working on this pressing issue through her involvement in the LUX-ZEPLIN experiment in the United States. This project uses lead to help in the search for dark matter particles. She described the challenges faced by researchers in this field: “We’re going to run a detector, which is seven tonnes of xenon, for 1,000 days and we expect maybe a handful of events.” The infrequency of such events highlights the difficulty involved with dark matter research.
Fruth elaborated on the significance of unraveling dark matter’s mysteries: “It’s just this really big problem … We don’t know what 85 percent of the matter in our Universe is made out of.” Individually, she thinks that understanding dark matter will deepen humanity’s scientific knowledge. It could give us more profound insight into what humanity’s role is in the universe. Figuring that out would teach us how to understand the world a bit more, she added.
The Future of Dark Matter Research
As researchers continue their investigations into dark matter, projects like the SABRE South detector are set to make significant strides. We’re looking forward to deploying this new detector to begin monitoring early 2026 at Victoria’s Stawell gold mine. Its aim is to find out whether the signals observed by past experiments, such as DAMA/LIBRA, indicate a real dark matter particle or whether they are a result of experimental mistakes.
Just as the current raced arc for dark matter exemplifies the breathtaking technological leaps in physics, perhaps most importantly, it highlights the important collaboration occurring between archaeology and modern science. The ancient lead recovered from Roman shipwrecks stands as a testament to how historical artefacts can play an integral role in contemporary scientific inquiry.
As scientists work through these challenges, they are dedicated to upholding ethical considerations while furthering the pursuit of knowledge. Dr. Perez-Alvaro aptly summarized this struggle: “It was like a war between those who defended the past and those who defended the future.”
