In this illustration of a proton’s internal structure, quarks (represented by the letters U and D) are held together by the strong nuclear force (helices), which is imparted by particles called gluons.
Mark Garlick/Science Photo Library/Getty Images Plus
What holds the proton together — Science News , September 16, 1972
An experiment … at the CERN Laboratory in Geneva … gives an important clue to structural arrangements deep within the proton…. The result hints at the existence of a new and very strong fundamental interaction — the process that holds [quarks] together inside the protons.… A number of theorists have speculated about its nature and have even proposed an intermediate particle for it called a gluon.
Physicists finally found evidence for gluons in 1979, in the aftermath of electron-positron collisions at a German particle accelerator ( SN: 4/21/79, p. 262 ). Gluons bind quarks inside protons via the strong force — the most powerful force in nature. Recent investigations of gluons’ role inside the proton suggest the particles’ energy makes up about 36 percent of the proton’s mass ( SN: 12/22/18 & 1/5/19, p. 8 ). Future particle accelerators could gauge gluons’ contribution to the proton’s internal pressure , which averages a million trillion trillion times the strength of Earth’s atmospheric pressure ( SN: 6/9/18, p. 10 ).
A version of this article appears in the September 10, 2022 issue of Science News .
Science News Staff. A hint of what holds the proton together . Science News . Vol. 102, September 16, 1972, p. 180.
Previously the staff writer for physical sciences at Science News , Maria Temming is the assistant editor at Science News Explores . She has bachelor’s degrees in physics and English, and a master’s in science writing.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.
Not a subscriber?
Become one now .
