Electrons occupy a space that surrounds an atom's nucleus. Each electron has an electrical charge of Quarks make up protons and neutrons, which, in turn, make up an atom's nucleus. Each proton and each neutron contains three quarks. A quark is a fast-moving point of energy. These measurements are already helping to nail down the structure of the proton at the smallest scales. Navbar Toggle. News at work COVID resources for employees Calendar — Note cancellations and changes Search all laboratory news From lab leadership Submit content — login required Provide feedback Subscribe to our newsletter — login required.
Fermilab news Search. Although we usually say that a proton contains three quarks up, up and down , there are many more quark-antiquark pairs at fine scales. After years of effort, the above physicists are stepping down from senior leadership roles in CMS. One approach has been to infer incalculable values by watching how quarks behave in experiments.
Other researchers have continued to try to wring information from the canonical QCD equation by calculating approximate solutions using supercomputers. This computational approach, known as lattice QCD, turns computers into laboratories that model the behavior of digital quarks and gluons. The technique gets its name from the way it slices space-time into a grid of points.
Quarks sit on the lattice points, and the QCD equation lets them interact. The denser the grid, the more accurate the simulation. The Fermilab physicist Andreas Kronfeld remembers how, three decades ago, these simulations had just a handful of lattice points on a side. Theorists thought these digital laboratories were still a year or two away from becoming competitive with the collider experiments in approximating the effects quarks have on other particles.
Meyer, who recently co-authored a survey of the conflicting results , says that many technical details in lattice QCD remain poorly understood, such as how to hop from the gritty lattice back to smooth space. Efforts to determine what QCD predicts for the muon, which many researchers consider a bellwether for undiscovered particles, are ongoing.
One such Hail Mary pass in the theoretical world is a tool called the holographic principle. The general strategy is to translate the problem into an abstract mathematical space where some hologram of quarks can be separated from each other, allowing an analysis in terms of Feynman diagrams. Simple attempts look promising, according to Tanedo, but none come close to the hard-won accuracy of lattice QCD. For now, theorists will continue to refine their imperfect tools and dream of new mathematical machinery capable of taming the fundamental but inseparable quarks.
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