The latest search for dark matter has so far been fruitless, but the good news is that it has allowed physicists to place the toughest constraints yet on the properties of this mysterious substance. New measurements from the LUX-ZEPLIN (LZ) experiment in South Dakota mean that we are closer than ever to finding dark matter particles, or that we have refuted the most likely explanation.

Dark matter is invisible to the naked eye because it does not interact significantly with normal matter or light. We only know that dark matter exists through its gravitational effects, which tell us that it makes up more than 80 percent of all matter. The leading explanation for dark matter has been that it is composed of weakly interacting massive particles (WIMPs), but searches for these fundamental entities have yet to turn up anything.

LUX-ZEPLIN is a dark matter detector made of seven tonnes of liquid xenon buried 1.5 kilometres underground and is the most sensitive to date, but after 280 days of searching it has yet to find any WIMPs. “We are number one in the world at not finding dark matter,” says an LZ spokesman. Chamkaur Gag At University College London.

While this result may seem disappointing, it allows physicists to place tight constraints on the nature of dark matter, narrowing the range of properties it could have. The constraints are nearly five times tighter than the best known, significantly limiting the possibility of WIMPs. The work was presented at two physics conferences. TeV Particle Astrophysics In the United States lysine It will be held in Brazil on August 26th.

“It’s like they say there’s a magic fish in the ocean, but we don’t know where it is,” Gag says. “You go in and swim around, you get out, you snorkel around, and you still don’t find it, so you use a submarine.” If the magic fish is a WIMP, he says, researchers have explored about 75 percent of the oceans and still haven’t found it.

“This is the next big step forward, one in a long line of such steps.” Dan Hooper “It’s probably fair to say that at any of these steps forward we can’t expect to see anything, but it doesn’t seem unlikely that we’ll see something if we take enough of these steps,” said David G. Schneider, a researcher at Fermi National Accelerator Laboratory in Illinois who was not involved in the study.

At this point, many of the initially popular ideas for possible types of WIMPs have been ruled out. There are still a few left, but LZ isn’t done yet. It plans to observe for a total of 1,000 days before wrapping up in 2028. “If LZ doesn’t detect a WIMP, and our next-generation detector, XLZD, doesn’t detect a WIMP, then WIMPs are over,” Gag says. The XLZD project is still in the planning stages.

If WIMPs don’t constitute dark matter, it would be a major paradigm shift, but physicists aren’t giving up on finding dark matter entirely. “If you’re trying to solve a murder investigation and you have 20 suspects, 10 of them are unaware,” he says. [alibis]”We don’t go, ‘Oh, it looks like it wasn’t a murder.’ We just get a better idea of who the right suspects are,” Hooper said. “We take some suspects off our list, we narrow the scope of the investigation, we narrow the focus. That’s what progress looks like in this field.”