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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

May 24, 2026

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 ...
Scientists in Germany have demonstrated a startling new form of surveillance: identifying people using nothing more than ordinary WiFi signals. By analyzing how radio waves bounce around a room, researchers can effectively “see” and recognize ...
Researchers have discovered how to fine-tune a futuristic type of porous glass that can trap gases like CO2 and hydrogen. Inspired by centuries-old glassmaking techniques, the team added sodium and ...
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 ...
Researchers have built an ultra-sensitive sensor capable of detecting unimaginably small amounts of energy — below one zeptojoule. The breakthrough relies on fragile superconducting materials that react to even the slightest temperature change. ...
Scientists in Canada have discovered that ancient underground rocks are naturally producing hydrogen gas — and lots of it. Measurements from mine boreholes in Ontario show the gas can flow continuously for years, offering a potential new source of ...
Researchers have developed a light-driven method for creating tiny, high-energy “housane” molecules that are valuable for drug development and materials science. These compact ring-shaped structures are difficult to produce because of the ...
Scientists spent decades chasing signs of a mysterious new force hidden inside the muon, one of nature’s strangest particles. But after years of supercomputer calculations, researchers discovered the apparent anomaly was likely a calculation error ...
Scientists at the University of Cambridge have achieved what was once considered impossible by electrically powering insulating nanoparticles to create a completely new kind of LED. Using tiny organic “molecular antennas,” the team found a way ...
Researchers have developed a durable new catalyst that produces clean hydrogen without relying on expensive platinum metals. The breakthrough could make renewable hydrogen fuel cheaper, more efficient, and easier to scale for real-world energy ...
Electric vehicles are pushing scientists to tackle one of the biggest hidden energy drains inside electric motors: magnetic energy loss. Now, researchers in Japan have developed a powerful AI-driven ...

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