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Entropy

In thermodynamics, entropy is an extensive state function that accounts for the effects of irreversibility in thermodynamic systems, particularly in heat engines during an engine cycle. While the concept of energy is central to the first law of thermodynamics, which deals with the conservation of energy, the concept of entropy is central to the second law of thermodynamics, which deals with physical processes and whether they occur spontaneously. Spontaneous changes occur with an increase in entropy. Entropy change has often been defined as a change to a more disordered state at a microscopic level. In recent years, entropy has been interpreted in terms of the "dispersal" of energy.

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Matter & Energy News

May 31, 2026

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Scientists at the University of Houston have shattered a long-standing superconductivity record, creating a material that can conduct electricity with zero resistance at the highest temperature ever achieved under normal pressure conditions. Their ...
A new AI-powered chip from UC Davis can analyze light and chemicals using a device tiny enough to fit almost anywhere. By combining smart silicon sensors with machine learning, it achieves lab-style ...
Scientists have directly watched angular momentum move through a crystal for the very first time — and discovered a bizarre twist along the way. Using ultra-powerful terahertz laser pulses, researchers triggered tiny atomic rotations inside a ...
A breakthrough lithium-extraction method could help solve one of clean energy’s dirtiest problems. Researchers at Columbia Engineering have developed a fast new technique that pulls lithium ...
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Scientists have finally figured out how mysterious “breather” laser pulses work, solving a puzzle that has frustrated laser physicists for years. These unusual ultrafast lasers produce light pulses that rhythmically grow and shrink instead of ...

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