absolute zero

noun

|Updated on: 22 Jun 2018

: a theoretical temperature characterized by complete absence of heat and motion and equivalent to exactly −273.15°C or −459.67°F

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Recent Examples of absolute zero from the Web

To create the condensate, other cooling techniques are used to push the cloud even closer to absolute zero—including creaming off the most energetic atoms using a radio-wave ‘knife’ and widening the trap to let the cloud expand.

— elizabeth gibney, Scientific American, "Universe’s Coolest Lab Set to Open Quantum World," 9 May 2018
The researchers connected the chips with an optical fiber and cooled the whole setup close to absolute zero to damp out vibrations.

— gabriel popkin, Science | AAAS, "Einstein’s ‘spooky action at a distance’ spotted in objects almost big enough to see," 25 Apr. 2018
One piece of equipment that the rocket will carry is the Cold Atom Laboratory, which will use magnetic fields and lasers to create clouds of atoms called Bose-Einstein condensates (BECs), cooled to just above absolute zero.

— andrew liptak, The Verge, "Orbital ATK will launch an Antares rocket to the International Space Station tomorrow morning," 20 May 2018
That’s long enough for them to be cooled to record-low temperatures—perhaps as little as 20 trillionths of a degree above absolute zero.

— elizabeth gibney, Scientific American, "Universe’s Coolest Lab Set to Open Quantum World," 9 May 2018
Researchers have used lasers to get things down to millionths of a degree above absolute zero.

— john wenz, Popular Mechanics, "Learn the Counterintuitive Genius of Laser Cooling In Just Six Minutes," 31 Mar. 2016
Chocolate bunnies melt in a car when temperatures reach anything north of absolute zero.

— chris lykins, San Antonio Express-News, "Weekend Weather: Checking the chocolate bunny melt index," 31 Mar. 2018
Unlike Hubble, which resides in low-Earth orbit and has been kept alive by repeated servicing missions, Webb would be stationed beyond the orbit of the moon and cooled nearly to absolute zero by its sunshield.

— lee billings, Scientific American, "NASA's James Webb Space Telescope Slips to 2020, and Astronomy Suffers," 27 Mar. 2018
After spending three months at a temperature of just 20 degrees Celsius above absolute zero, the massive James Webb Space Telescope emerged from a large vacuum chamber at the end of 2017.

— eric berger, Ars Technica, "The James Webb Space Telescope has emerged from the freezer," 15 Jan. 2018

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