Researchers at the National Institute of Standards and Technology are in the early stages of a massive undertaking to design and build a fleet of tiny ultra-sensitive thermometers. If they succeed, their system will be the first to make real-time measurements of temperature on the microscopic scale in an opaque 3D volume — which could include medical implants, refrigerators, and even the human body. The project will work by using nanometer-sized objects whose magnetic signals change with temperature.
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