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Reference Terms
from Wikipedia, the free encyclopedia

Energy

In general, the word energy refers to a concept that can be paraphrased as "the potential for causing changes", and therefore one can say that energy is the cause of any change. The most common definition of energy is the work that a certain force (gravitational, electromagnetic, etc) can do. Due to a variety of forces, energy has many different forms (gravitational, electric, heat, etc.) that can be grouped into two major categories: kinetic energy and potential energy. According to this definition, energy has the same units as work; a force applied through a distance. The SI unit of energy, the joule, equals one newton applied through one meter, for example. Energy has no direction in space, and is therefore considered a scalar quantity.

Energy is a conserved quantity, meaning that it cannot be created or destroyed, but only converted from one form into another. Thus, the total energy of the universe always remains constant. One form of energy can be readily transformed into another; for instance, a battery converts chemical energy into electrical energy.

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Matter & Energy News

December 28, 2025

Researchers found that U.S. metal mines already contain large amounts of critical minerals that are mostly going unused. Recovering even a small fraction of these byproducts could sharply reduce dependence on imports for materials essential to clean ...
A shiny gray crystal called platinum-bismuth-two hides an electronic world unlike anything scientists have seen before. Researchers discovered that only the crystal’s outer surfaces become superconducting—allowing electrons to flow with zero ...
Scientists are digging into the hidden makeup of carbon-rich asteroids to see whether they could one day fuel space exploration—or even be mined for valuable resources. By analyzing rare meteorites ...
A new discovery shows that messy, stray light can be used to clean up quantum systems instead of disrupting them. University of Iowa researchers found that unwanted photons produced by lasers can be canceled out by carefully tuning the light itself. ...
Superconductors promise loss-free electricity, but most only work at extreme cold. Hydrogen-rich materials changed that—yet their inner workings remained hidden because they only exist under enormous pressure. Now, researchers have directly ...
Gravitational waves from black holes may soon reveal where dark matter is hiding. A new model shows how dark matter surrounding massive black holes leaves detectable fingerprints in the waves recorded by future space ...
Researchers in Sweden have unveiled a way to create high-performance electronic electrodes using nothing more than visible light and specially designed water-soluble monomers. This gentle, chemical-free approach lets conductive plastics form ...
Researchers at the University of Warsaw have unveiled a breakthrough method for detecting and precisely calibrating terahertz frequency combs using a quantum antenna made from Rydberg atoms. By combining atomic electrometry with a powerful ...
MOCHI uses microscopic, air-filled channels to stop heat in its tracks while remaining nearly crystal clear. If scaled up, it could transform windows into powerful energy savers and solar ...
Scientists developed a high-performance hydrogen-production catalyst using lignin, a common waste product from paper and biorefinery processes. The nickel–iron oxide nanoparticles embedded in carbon fibers deliver fast kinetics, long-term ...
SQUIRE aims to detect exotic spin-dependent interactions using quantum sensors deployed in space, where speed and environmental conditions vastly improve sensitivity. Orbiting sensors tap into ...
Scientists have discovered how to electrically power insulating nanoparticles using organic molecules that act like tiny antennas. These hybrids generate extremely pure near-infrared light, ideal for medical diagnostics and advanced communications. ...

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updated 12:56 pm ET