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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 13, 2026

Scientists in Japan have developed a new way to instantly detect elusive quantum “W states,” a major milestone for quantum technology. The breakthrough could help unlock faster quantum communication, teleportation, and powerful new computing ...
A new quantum-inspired algorithm has cracked a problem so massive that conventional supercomputers struggle to even approach it. Researchers used the method to simulate extraordinarily complex quantum materials known as quasicrystals, opening the ...
A team at the University of Hong Kong has developed a new “super steel” that can survive the harsh conditions needed to make green hydrogen from seawater. The material uses an unexpected double-protection mechanism that resists corrosion far ...
Scientists have taken a major step toward ultra-secure quantum communication by demonstrating a remarkably stable quantum encryption system that worked across more than 120 kilometers of optical fiber. Using tiny semiconductor quantum dots that emit ...
A major obstacle may be standing in the way of the next generation of ultra-tiny computer chips. Researchers discovered that many promising 2D materials lose their advantages because an invisible atomic-scale gap forms when they are combined with ...
Cumberland, B.C. is reimagining its coal mining past as a clean energy opportunity. Water trapped in abandoned mine tunnels could be used in a geothermal system to heat and cool buildings efficiently and with minimal emissions. The project could ...
A powerful new electromagnetic thruster has taken a major step forward after a successful high-energy test at NASA’s Jet Propulsion Laboratory. Fueled by lithium vapor and driven by intense magnetic forces, the experimental engine reached ...
Creating complex molecules usually requires years of experience and countless decisions, but a new AI system is changing that. Synthegy lets chemists guide synthesis and reaction planning using simple language, while powerful algorithms generate and ...
A strange kind of matter that “ticks” forever without energy input has just taken a major leap toward real-world use. Known as a time crystal, this quantum system repeats its motion ...
Researchers at Stanford have developed a compact optical amplifier that dramatically boosts light signals using very little power. By recycling energy inside a looping resonator, the device achieves strong amplification with minimal noise and wide ...
A new quantum physics study reveals that simply changing a magnetic field over time can unlock entirely new forms of matter that don’t exist under normal conditions. By carefully “driving” materials with timed magnetic shifts, researchers ...
Scientists are using sunlight to turn plastic waste into clean fuels like hydrogen, offering a breakthrough solution to both pollution and energy challenges. While still in development, the approach could transform trash into a valuable resource for ...

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