The proton, one of the fundamental building blocks of matter, has been sent through the looking glass. For the first time, physicists have measured how it is affected by the weak force, the only fundamental force to treat objects and their mirror images differently.
The result is consistent with the standard model of particle physics – something of a disappointment for those hoping nature's weirdest force would reveal something more exotic. But it's also a preliminary finding, so the force could yet point the way to new physics beyond the standard model.
Nature has four known forces – the electromagnetic force, which gives rise to positive and negative charge, gravity and the strong and weak forces. But the weak force, which acts only on the subatomic level and is responsible for radioactive decay, has an odd quirk.
If you're on a water slide, gravity pulls you along at the same rate, whether the slide turns clockwise or counter-clockwise. But in the subatomic equivalent of these situations, the weak force behaves differently. "If you do an experiment and compare it with a mirror-image of that experiment, you get different results," says Shelley Page, a physicist at the University of Manitoba, Canada, and part of the Q-weak collaboration, which made the latest measurement.To read more, click here.