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NIST Nobel Laureate Explains “Science of Cold” to 800 Middle School Students
Teachers: To receive a free DVD with the full 54-minute presentation described below, send a request to inquiries@nist.gov. To view the entire presentation in Flash format, visit this page or watch the clip below. To view the introductions by by Benjamin OuYang, acting principal of Parkland Middle School; Jerry Weast, superintendent of Montgomery County Public Schools, Md.; Senator Chris Van Hollen; and Linda Devillier, president of Devillier Communications, click here. “You are the kind of audience that I most like talking to. Let me show you why,” Nobel Laureate William Phillips said with a devilish grin before upending a decanter full of liquid nitrogen. The supercold liquid began to boil on contact with the air and the stage and produced a wispy fog as it evaporated. The children leapt to their feet with a collective gasp of amazement. Phillips continued, “The grown-ups are saying ‘Whoa, that looks dangerous. I hope nothing bad is going to happen.’ But you all are curious about what's going on, and curiosity is what makes a scientist a scientist.” Phillips, a physicist at the Commerce Department’s National Institute of Standards and Technology (NIST), spoke about the science of cold temperatures to approximately 800 students, parents and teachers at Parkland Magnet Middle School for Aerospace Technology in Rockville, Md., on Jan. 9, 2008. He showed how the properties of everyday materials—from inflated balloons that become flat as Frisbees to carnations that shatter like glass—change drastically at cold temperatures. In attendance were U.S. Representative Chris Van Hollen, Montgomery County Public Schools (MCPS) Superintendent Jerry Weast, NIST Acting Director James Turner, as well as other NIST and MCPS officials.
The presentation was given in conjunction with the airing of the PBS NOVA program “Absolute Zero." At approximately -273.15 Celsius or -459.67 Fahrenheit, absolute zero is the bottommost rung of the temperature scale and where all thermal motion stops. Phillips described how in his and other NIST labs such as that of Eric Cornell in Boulder, Colo., they create temperatures much colder than the deepest parts of outer space, only billionths of a degree above absolute zero. Cornell is featured extensively in the second half of the program airing at 8 p.m. EST on Tuesday, Jan. 15 on NOVA. As the NOVA program points out, cold temperatures make much of modern life possible from enjoying fresh foods months after they have been harvested, to building skyscrapers that could not exist without air conditioning, to medical equipment like MRI machines that depend on supercooled magnets. Phillips added to this list by telling the students how ultracold temperatures have allowed scientists at NIST to build the world’s most accurate atomic clock, which would neither gain nor lose a second in 60 million years. Extreme cold can make some materials become superconductive, a state in which they are able to conduct electricity without resistance, and other materials become superfluids that flow up the sides of their containers against the pull of gravity. Bose-Einstein Condensates, a special form of matter first produced by Cornell and his colleagues, are created at the cusp of absolute zero. After the presentation, Phillips opened the floor to questions. Dozens of hands shot up. One student wondered whether there were such a thing as absolute hot, to which Phillips answered that there isn’t a limit to the amount of energy that can be put into a system, but there’s nothing slower (i.e. colder) than stopped. Phillips shared the 1997 Nobel Prize in physics “for development of methods to cool and trap atoms with laser light.” NIST is in the process of producing a video of the event that will be made available to teachers who wish to share the program with their students. The PBS NOVA program “Absolute Zero” can be viewed online at http://www.pbs.org/wgbh/nova/zero/program.html. created on 01/11/08
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