New! Sign up for our free email newsletter.
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.

Related Stories
 


Matter & Energy News

April 8, 2026

Quantum circuits are supposed to gain power as they grow longer, but noise changes the picture. A new study finds that earlier steps in these circuits gradually lose their impact, with only the final layers really mattering. As a result, deep ...
Scientists have taken a major step toward futuristic energy tech by building a working prototype of a quantum battery—one that can charge, store, and release energy using the strange rules of quantum physics instead of chemistry. This tiny, ...
A new breakthrough is transforming MXenes—ultra-thin, high-tech materials—into something far more powerful and precise. Researchers have developed a cleaner, more controlled way to build these materials using molten salts and iodine, eliminating ...
Fusion scientists have solved a long-standing mystery inside tokamaks, the donut-shaped machines designed to harness fusion energy. For years, experiments showed that escaping plasma particles hit one side of the exhaust system far more than the ...
Scientists have transformed a groundbreaking 2D nanomaterial called MXene into an even more powerful 1D form—tiny scroll-like tubes that are incredibly thin yet highly conductive. By rolling flat ...
A new shape-shifting material can change both its texture and color in seconds, inspired by the camouflage abilities of octopuses. By precisely controlling how a polymer swells with water, ...
Scientists have taken lasers beyond light and into the realm of sound, creating a breakthrough “phonon laser” that manipulates tiny vibrations at the quantum level. By dramatically reducing noise ...
Perovskite crystals can dramatically and reversibly change shape when hit with light, a behavior not seen in conventional semiconductors. This effect, called photostriction, can be finely tuned depending on the light’s intensity and color. ...
A new holographic storage technique uses light in three dimensions to dramatically increase how much data can be stored. It encodes information throughout a material using amplitude, phase, and ...
A new solar breakthrough may overcome a long-standing efficiency barrier. Researchers used a “spin-flip” metal complex to capture and multiply energy from sunlight through singlet fission. The result reached about 130% efficiency, meaning more ...
Scientists have created a new kind of carbon material that could make carbon capture much cheaper and more efficient. By carefully controlling how nitrogen atoms are arranged, they found certain structures capture CO2 better and release it using far ...
Researchers have uncovered a new way to generate exotic oscillation states in tiny magnetic structures—using only minimal energy. By exciting magnetic waves, they triggered a delicate motion that produced a rich spectrum of signals never seen ...

Latest Headlines

updated 12:56 pm ET