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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

October 23, 2025

Scientists have developed a chromium-molybdenum-silicon alloy that withstands extreme heat while remaining ductile and oxidation-resistant. It could replace nickel-based superalloys, which are limited to about 1,100°C. The new material might make ...
Researchers have found that 2D materials can self-form microscopic cavities that trap light and electrons, altering their quantum behavior. With a miniaturized terahertz spectroscope, the team observed standing light-matter waves without needing ...
A new light-driven cancer therapy uses LEDs and tin nanoflakes to kill tumors safely and affordably. Developed by teams in Texas and Portugal, it eliminates up to 92% of skin cancer cells without ...
Researchers from NTNU and EPFL have unveiled a compact, low-cost laser that outperforms current models in speed, control, and precision. Built using microchip technology, it can be mass-produced for use in everything from Lidar navigation to gas ...
A collaboration between the University of Michigan and AFRL has resulted in 3D-printed metamaterials that can block vibrations using complex geometries. Inspired by nature and theoretical physics, these “kagome tubes” demonstrate how geometry ...
Researchers discovered how to stabilize a high-performance sodium compound, giving sodium-based solid-state batteries the power and stability they’ve long lacked. The new material conducts ions far ...
A team of engineers at North Carolina State University has designed a polymer “Chinese lantern” that can rapidly snap into multiple stable 3D shapes—including a lantern, a spinning top, and more—by compression or twisting. By adding a ...
Scientists have developed an ultra-thin, paper-like LED that emits a warm, sunlike glow, promising to revolutionize how we light up our homes, devices, and workplaces. By engineering a balance of red, yellow-green, and blue quantum dots, the ...
Scientists at EPFL have reimagined 3D printing by turning simple hydrogels into tough metals and ceramics. Their process allows multiple infusions of metal salts that form dense, high-strength structures without the porosity of earlier methods. ...
Researchers have found a way to extract almost every photon from diamond color centers, a key obstacle in quantum technology. Using hybrid nanoantennas, they precisely guided light from nanodiamonds into a single direction, achieving 80% efficiency ...
In a remarkable leap for quantum physics, researchers in Japan have uncovered how weak magnetic fields can reverse tiny electrical currents in kagome metals—quantum materials with a woven atomic structure that frustrates electrons into forming ...
An international team has confirmed that large quantum systems really do obey quantum mechanics. Using Bell’s test across 73 qubits, they proved the presence of genuine quantum correlations that can’t be explained classically. Their results show ...

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