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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 11, 2026

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A major obstacle may be standing in the way of the next generation of ultra-tiny computer chips. Researchers discovered that many promising 2D materials lose their advantages because an invisible atomic-scale gap forms when they are combined with ...
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Researchers at Stanford have developed a compact optical amplifier that dramatically boosts light signals using very little power. By recycling energy inside a looping resonator, the device achieves strong amplification with minimal noise and wide ...
A new quantum physics study reveals that simply changing a magnetic field over time can unlock entirely new forms of matter that don’t exist under normal conditions. By carefully “driving” materials with timed magnetic shifts, researchers ...
Scientists are using sunlight to turn plastic waste into clean fuels like hydrogen, offering a breakthrough solution to both pollution and energy challenges. While still in development, the approach could transform trash into a valuable resource for ...
For decades, relaxor ferroelectrics have powered everything from medical ultrasounds to sonar systems, yet their inner atomic structure remained a mystery—until now. Researchers have finally mapped ...
In a striking glimpse into extreme physics, scientists have captured the split-second chaos that unfolds when powerful laser flashes blast matter into a superheated plasma. By combining two cutting-edge lasers, researchers were able to track how ...

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