weak force


Definition of weak force

: a fundamental physical force that governs interactions between hadrons and leptons (as in the emission and absorption of neutrinos) and is responsible for particle decay processes (such as beta decay) in radioactivity, that is 10-5 times the strength of the strong force, and that acts over distances smaller than those between nucleons in an atomic nucleus

called also weak interaction, weak nuclear force

— compare electromagnetism sense 2a, gravity sense 3a(2), strong force

Examples of weak force in a Sentence

Recent Examples on the Web Finally, direct detection experiments like LZ and SuperCDMS hope that dark matter particles occasionally interact with normal matter via the weak force, allowing them to be spotted by extremely sensitive detectors. Emily Toomey, Smithsonian Magazine, "New Generation of Dark Matter Experiments Gear Up to Search for Elusive Particle," 3 Feb. 2020 These particles convey one of the four fundamental forces, called the weak force, which causes radioactive decay. Quanta Magazine, "A Call for Courage as Physicists Confront Collider Dilemma," 7 Aug. 2019 To find dark matter, physicists like Cushman are banking on the particles to interact with normal matter through the weak force. Emily Toomey, Smithsonian Magazine, "New Generation of Dark Matter Experiments Gear Up to Search for Elusive Particle," 3 Feb. 2020 The requirement here was to seize the people by means of a methodically correct procedure, with the weak forces available, reducing to a minimum economic damage to war production. Debbie Cenziper, Washington Post, "The Mystery of the Trawniki Nazis," 23 Jan. 2020 The breaking of the Higgs symmetry created massive spin-1 particles called W and Z bosons, the carriers of the weak force that’s responsible for radioactive decay. Quanta Magazine, "Why the Laws of Physics Are Inevitable," 9 Dec. 2019 Yet gravity is fundamentally a mystery, writer Panek reveals in this beautiful and philosophical investigation of nature’s weakest force. Andrea Gawrylewski, Scientific American, "Recommended Books, October 2019," 1 Oct. 2019 The particle's existence would force a rewriting of the fundamental forces governing the universe, which up to now have included only the strong force, the weak force, the electromagnetic force and the gravitational force. Fox News, "Mysterious 'Particle X17' could carry fifth force of nature," 10 Dec. 2019 Here's an example: if a proton-antiproton collision produces a top quark and an antitop particle, these will instantly decay into two weak force (W) bosons and two bottom quarks. Jennifer Ouellette, Ars Technica, "MIT physicists: Social networks could hold the key to finding new particles," 31 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'weak force.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of weak force

1968, in the meaning defined above

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Cite this Entry

“Weak force.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/weak%20force. Accessed 11 Jul. 2020.

More from Merriam-Webster on weak force

Britannica.com: Encyclopedia article about weak force

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