Dark matter is composed of particles that do not absorb, reflect, or emit light, so they cannot be detected by observing electromagnetic radiation. It’s been calculated that dark matter is around five times more common than regular matter – and yet, we still haven’t directly detected it. Many different types of experiments are trying to find it, and now CERN has joined the hunt, testing whether the famous Higgs boson could decay into dark matter. The team of researchers examined the entire dataset from the second run of the LHC, which took place between 2015 and 2018. That’s about 100 quadrillion collisions. And in all that data, the researchers found no excess of invisible particle events over the background number that you’d expect from known processes in the Standard Model. From that, the team was able to narrow down the upper limit for how often the Higgs boson decays into invisible particles – no more than 13 percent of the time. That may still sound like a lot, but it’s coming down from previous models that suggested it could happen as often as 30 percent of the time. The researchers say that even though they didn’t find any signs of dark matter this time, the work still helps put constraints on the properties of the stuff. Between this and the many other experiments attempting to hunt it down, dark matter may be running out of places to hide. Or perhaps, we’re just getting closer to realising it doesn’t exist, and our models need to be tweaked. Either way, the search continues.