It’s not every day that scientists reduce the uncertainty in a fundamental constant of nature from 30% to 1.5%, but a team of theoretical physicists claims to have done just that. Using supercomputers and mind-bogglingly complex simulations, the researchers have calculated the masses of particles called “up quarks” and “down quarks” that make up protons and neutrons with 20 times greater precision than the previous standard. The new numbers could be a boon to theorists trying to decipher particle collisions at atom smashers like Europe’s Large Hadron Collider (LHC) or trying to develop deeper theories of the structure of matter. ...
The team finds that an up quark weighs 2.01 +/- 0.14 megaelectron-volts, whereas a down quark weighs 4.79 +/- 0.16 MeV. That’s 0.214% and 0.510% of the mass of the proton, respectively.
To read the rest of the article, click here.