Particle physics

An extensive search for a hypothetical particle has turned up empty. The sterile neutrino is a proposed subatomic particle that could even be a candidate for the mysterious dark matter, but two new experiments have all but ruled it out.

There’s invisible, undetectable stuff all around us, and we call it dark matter. There’s plenty of evidence that this stuff is very real, but what exactly is dark matter? How do we know it’s there? And how are scientists looking for it?

An experiment designed to hunt for ever elusive dark matter has returned some strange and exciting signals. Out of the three possible explanations, one is unwanted interference – while the other two would herald new physics.

Headlines lately have been screaming about how scientists in Antarctica have discovered evidence of a parallel universe where time runs backwards. While we seriously wish that was true, a new study has put forward a more realistic explanation.

There are billions of tiny particles called neutrinos streaming through your body right now. But where did they come from? Researchers have now traced back some ultra-high energy neutrinos to their points of origin – radio flares from raging quasars.

Unifying conflicting models into a “Theory of Everything” is the Holy Grail of physics. Now a NASA observatory has conducted an experimental test, scouring the sky for evidence of a hypothetical particle that could tie the universe together.

The Standard Model of particle physics still has some holes in it. Now, a new study outlines how one hypothetical particle, the axion, may be the answer to three separate, massive mysteries of the universe – including why we’re here at all.

Dark matter is believed to outnumber regular matter by a ratio of five-to-one, but so far it’s never been directly detected. Now, nuclear physicists have proposed a new candidate particle that might make up the stuff – and we’ve already found it.

The hunt for dark matter – the mysterious stuff that seems to outnumber regular matter by a ratio of five to one – has so far turned up no direct trace. Now, researchers at CERN have tried a new approach, using another strange substance – antimatter.

The detection of the Higgs boson at CERN in 2012 is one of the biggest scientific discoveries of the decade. Now the ATLAS and CMS Collaborations have made the most precise measurement of its mass to date.

Although it outnumbers regular matter by a ratio of five to one, dark matter is frustratingly elusive, and efforts to hunt down different types of candidate particles have revealed no direct trace. Now, researchers from Max Planck have proposed a new hypothetical particle that might be behind dark matter – the superheavy gravitino – and outlined just how we might find them.

Few things are as mysterious as dark matter. Now, a physicist from Johns Hopkins University has outlined a new theory that helps to explain the stuff but at the same time makes it seem even more bizarre. According to the study, dark matter may have originated before the Big Bang.