Dark matter has been measured where there is probably no dark matter

A dilemma arises from this. Dark matter detectors and other physical experiments often struggle with contamination of their radioactive material. However, as this age and radioisotope decay, the background tends to become quieter rather than louder. “The increased background noise is completely unnatural,” Lee says. However, Rossi and his team suspect that some effects, such as radioactive pollutants slowly infiltrating the detector from the outside, could in principle cause the background effect to increase.

says Dan Hooper, a dark matter specialist at the University of Chicago in Illinois.

Rita Burnaby, a DAMA/Libra spokeswoman, has expressed skepticism. “Because the Dama/Libra detector was built decades ago, and has been stored underground ever since, the radioactive background is much more stable than in the recently built experiments,” says the physicist from Tor Vergata University in Rome. “If there is a small hypothetical contribution from a descending rate, it may reduce the observed modulation amplitude, but it will never produce a positive signal like the one we observe,” she adds. The collaboration also contains Rossi group arguments In a paper, she described her assumptions as unacceptable and her conclusions worthless.

More data transparency is required

The physics community has repeatedly asked the Dama/Libra team to reveal more data, specifically the total number of signals. Burnaby says this does not provide any useful information. On the other hand, Nicolas Rossi suggests that additional transparency could be beneficial for collaboration: if the total number of background flashes turns out to be constant over time, that would make the team’s claim to see sinusoidal variability more credible. Dan Hooper agrees: “If Dama’s collaboration had been more open, this would have been discovered a long time ago.”

Meanwhile, attempts to observe dark matter continue. Earlier this month, Anais-112 scientists completed five years of data collection and are now working on the analysis, says spokeswoman Maria Luisa Sarsa of the University of Zaragoza in Spain. The data is so accurate that it would be able to rule out the Dama/Libra result with a high degree of statistical certainty. Within a few years, the confidence interval can then increase to five standard deviations—usually the threshold at which a physical outcome is considered sound.