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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

March 18, 2026

MIT physicists have built a powerful new microscope that uses terahertz light to uncover hidden quantum motions inside superconductors. By compressing this normally unwieldy light into a tiny region, ...
Physicists at UC Santa Barbara have uncovered a new way to manipulate unusual magnetic states by exploiting “frustration” inside a crystal’s atomic structure. The team discovered a rare system where two different kinds of ...
Scientists have developed a powerful new computational method that could accelerate the search for next-generation materials capable of turning sunlight into useful chemical energy. The work focuses on polyheptazine imides, a promising class of ...
Scientists are exploring a surprisingly simple way to clean up diesel engines: adding tiny droplets of water to the fuel. During combustion, the water rapidly vaporizes, triggering micro-explosions that improve fuel mixing and lower combustion ...
Scientists at Oak Ridge National Laboratory have created a new aluminum alloy called RidgeAlloy that can turn contaminated car-body scrap into strong structural vehicle parts. Normally, impurities ...
Scientists have found a way to significantly boost “blue energy,” which generates electricity from the mixing of saltwater and freshwater. By coating nanopores with lipid molecules that create a friction-reducing water layer, they enabled ions ...
Engineers have discovered an unexpected link between two very different realms of physics: the behavior of electrons in graphene and magnetic waves in specially engineered materials. By designing a thin magnetic film with a hexagonal pattern of ...
Solid-state batteries could be safer and more energy-dense than today’s lithium-ion technology, but finding materials that allow ions to move quickly through solid electrolytes has been difficult. ...
A team of physicists has experimentally confirmed a long-predicted sequence of exotic magnetic phases in an atomically thin material. When cooled, the material forms tiny magnetic vortices before transitioning into a second ordered magnetic ...
A new ultrathin photodetector from Duke University can sense light across the entire electromagnetic spectrum and generate a signal in just 125 picoseconds, making it the fastest pyroelectric detector ever built. The breakthrough could power ...
Scientists at the University of Tokyo have captured something never seen before: a frame-by-frame view of how electron spins flip inside an antiferromagnet, a material once thought to be magnetically “invisible.” By firing ultrafast electrical ...
Researchers at the University of Basel and the ETH in Zurich have succeeded in changing the polarity of a special ferromagnet using a laser beam. In the future, this method could be used to create adaptable electronic circuits with ...

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