Reference Terms
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Mass
Mass is a property of a physical object that quantifies the amount of matter it contains. Unlike weight, the mass of something stays the same regardless of location. Mass is a central concept of classical mechanics and related subjects, and there are several forms of mass within the framework of relativistic kinematics. In the theory of relativity, the quantity invariant mass, which in concept is close to the classical idea of mass, does not vary between single observers in different reference frames. In classical mechanics, there are three types of mass or properties called mass: Inertial mass; passive gravitational mass; and active gravitational mass. Although inertial mass, passive gravitational mass and active gravitational mass are conceptually distinct, no experiment has ever unambiguously demonstrated any difference between them.
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Matter & Energy News
March 3, 2026
Mar. 3, 2026 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 ...
Mar. 3, 2026 Fusion energy may be one of the most promising clean power sources of the future—but only if scientists can precisely measure the extreme, fast-moving plasmas that make it possible. A new U.S. Department of Energy–sponsored report urges major ...
Mar. 2, 2026 Twisting atomically thin magnetic layers does more than reshape their electronics—it can create giant, topological magnetic textures. In chromium triiodide, researchers observed skyrmion-like patterns stretching far beyond the expected moiré ...
Mar. 2, 2026 NYU researchers have found a way to use light to control how microscopic particles assemble into crystals, effectively turning illumination into a tool for shaping matter. By adding light-sensitive molecules to a liquid filled with tiny particles, ...
Mar. 1, 2026 Inverted perovskite solar cells offer strong potential for scalable, low-cost solar power, but a hidden interface inside the device has limited their performance and durability. Researchers have now introduced crystal-solvate nanoseeds that guide ...
Mar. 1, 2026 Scientists have pulled off a feat long considered out of reach: getting light to mimic the famous quantum Hall effect. In their experiment, photons drift sideways in perfectly defined, quantized steps—just like electrons do in powerful magnetic ...
Feb. 28, 2026 Scientists racing to tackle plastic pollution have created a surprising new contender: a biodegradable packaging film made partly from milk protein. Researchers at Flinders University blended calcium caseinate with starch and natural nanoclay to ...
Feb. 27, 2026 Researchers at Nagoya University have created a more efficient iron-based photocatalyst that could reduce the need for rare and expensive metals in advanced chemistry. Unlike earlier designs, the new catalyst uses far fewer costly chiral ligands ...
Feb. 27, 2026 Scientists have unveiled a breakthrough way to turn natural gas—long burned as fuel—into valuable chemical building blocks for medicines and other high-demand products. By designing a clever iron-based catalyst powered by LED light, researchers ...
Feb. 27, 2026 Engineers at UC Davis have built a remarkable device that creates power at night by tapping into something we rarely think about: the vast cold of outer space. Using a special type of Stirling engine, the system links the warmth of the ground to the ...
Feb. 26, 2026 Green hydrogen could be a game-changer for the clean energy transition—but right now, it’s too expensive and still relies on harmful “forever chemicals.” A new EU-backed project called SUPREME aims to fix that by reinventing how hydrogen is ...
Feb. 26, 2026 Researchers have discovered new ways to shape quantum light, creating high-dimensional states that can carry much more information per photon. Using advanced tools like on-chip photonics and ultrafast light structuring, they’re pushing quantum ...
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Feb. 25, 2026 Quantum computers need special materials called topological superconductors—but they’ve been notoriously difficult to create. Researchers have now shown they can trigger this exotic state by ...
Feb. 24, 2026 After nearly 50 years of failed attempts and scientific speculation, chemists at Saarland University have achieved what many thought might be ...
Feb. 24, 2026 CU Boulder researchers have designed microscopic “racetracks” that trap and amplify light with exceptional efficiency. By using smooth curves inspired by highway engineering, they reduced energy ...
Feb. 24, 2026 A sweeping nationwide study has found that U.S. counties located closer to operating nuclear power plants have higher cancer death rates than those farther away. Researchers analyzed data from every ...
Feb. 21, 2026 Scientists may have spotted a long-sought triplet superconductor — a material that can transmit both electricity and electron spin with zero resistance. That ability could dramatically stabilize ...
Feb. 21, 2026 Astronomers have uncovered one of the most mysterious galaxies ever found — a dim, ghostly object called CDG-2 that is almost entirely made of dark ...
Feb. 20, 2026 Qubits, the heart of quantum computers, can change performance in fractions of a second — but until now, scientists couldn’t see it happening. Researchers at NBI have built a real-time monitoring ...
Feb. 20, 2026 Oxford researchers have found a way to visualize one of the most hidden — yet critical — components inside lithium-ion batteries. By tagging ...
Feb. 19, 2026 Scientists have taken a major step toward mimicking nature’s tiniest gateways by creating ultra-small pores that rival the dimensions of biological ion channels—just a few atoms wide. The ...
Feb. 19, 2026 Scientists at the University of New Hampshire have unleashed artificial intelligence to dramatically speed up the hunt for next-generation magnetic materials. By building a massive, searchable ...