mass·​less | \ ˈmas-ləs How to pronounce massless (audio) \

Definition of massless

: having no mass a massless particle

Examples of massless in a Sentence

Recent Examples on the Web And photons—massless packets of light energy—can, in exceedingly rare cases, spontaneously transform into gravity particles, according to Douglas Singleton, a physicist at California State University, who was not involved with the new study. Charlie Wood, Scientific American, "Simulation Shows Potential for Glowing Gravitons," 1 July 2020 The spin spectrum stops at 2 because the infinities in the four-particle interaction equation kill off all massless particles that have higher spin values. Quanta Magazine, "Why the Laws of Physics Are Inevitable," 9 Dec. 2019 The spectacular explosion created a hot, compact, and opaque particle soup that trapped even massless photons. Akshat Rathi, Quartz, "Winners of the 2019 Nobel Prize in physics expanded our understanding of the universe," 8 Oct. 2019 They're known for traveling at near lightspeeds and being nearly massless, but a new study has shown the masslessness of the most massless neutrino. David Grossman, Popular Mechanics, "Ghost Particles Could Explain Just About Everything in the Universe," 23 Aug. 2019 Neutrinos are nearly massless subatomic particles that have no electric charge and therefore interact rarely with their surroundings. Mike Wall, NBC News, "High-energy 'ghost particle' traced to distant galaxy in astronomy breakthrough," 12 July 2018 Models at the time predicted that certain fundamental particles would be massless, but the mechanism that the three physicists proposed explained how these particles could have mass. Steph Yin, New York Times, "Tom Kibble, Physicist Who Helped Discover the Higgs Mechanism, Dies at 83," 19 July 2016 Such flavor changing shows that neutrinos cannot be massless. Adrian Cho, Science | AAAS, "Weighing the universe's most elusive particle," 29 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'massless.' 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 massless

1879, in the meaning defined above

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Time Traveler for massless

Time Traveler

The first known use of massless was in 1879

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Cite this Entry

“Massless.” Dictionary, Merriam-Webster, Accessed 23 Sep. 2020.

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