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
February 7, 2026
Feb. 6, 2026 Inspired by the shape-shifting skin of octopuses, Penn State researchers developed a smart hydrogel that can change appearance, texture, and shape on command. The material is programmed using a ...
Feb. 6, 2026 Quantum computers struggle because their qubits are incredibly easy to disrupt, especially during calculations. A new experiment shows how to perform quantum operations while continuously fixing errors, rather than pausing protection to compute. The ...
Feb. 5, 2026 Researchers have built a paper-thin chip that converts infrared light into visible light and directs it precisely, all without mechanical motion. The design overcomes a long-standing efficiency-versus-control problem in light-shaping materials. This ...
Feb. 5, 2026 A new metasurface design lets light of different spins bend, focus, and behave independently—while staying sharp across many colors. The trick combines two geometric phase effects so each spin channel can be tuned without interfering with the ...
Feb. 4, 2026 A new optical device allows researchers to generate and switch between two stable, donut-shaped light patterns called skyrmions. These light vortices hold their shape even when disturbed, making them promising for wireless data transmission. Using a ...
Feb. 3, 2026 Researchers have found that manganese, an abundant and inexpensive metal, can be used to efficiently convert carbon dioxide into formate, a potential hydrogen source for fuel cells. The key was a clever redesign that made the catalyst last far ...
Feb. 2, 2026 A new light-based breakthrough could help quantum computers finally scale up. Stanford researchers created miniature optical cavities that efficiently collect light from individual atoms, allowing many qubits to be read at once. The team has already ...
Feb. 1, 2026 Researchers have discovered a hidden quantum geometry inside materials that subtly steers electrons, echoing how gravity warps light in space. Once thought to exist only on paper, this effect has now been observed experimentally in a popular quantum ...
Jan. 31, 2026 A strange, glowing form of matter called dusty plasma turns out to be incredibly sensitive to magnetic fields. Researchers found that even weak fields can change how tiny particles grow, simply by nudging electrons into new motions. In lab ...
Jan. 30, 2026 Researchers have found a way to make ordinary aluminum tubes float indefinitely, even when submerged for long periods or punched full of holes. By engineering the metal’s surface to repel water, the tubes trap air inside and refuse to sink, even ...
Jan. 29, 2026 Order doesn’t always form perfectly—and those imperfections can be surprisingly powerful. In materials like liquid crystals, tiny “defects” emerge when symmetry breaks, shaping everything ...
Jan. 29, 2026 Scientists have created a device that captures carbon dioxide and transforms it into a useful chemical in a single step. The new electrode works with realistic exhaust gases rather than requiring purified CO2. It converts the captured gas into ...
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Feb. 7, 2026 Astronomers propose that an ultra-dense clump of exotic dark matter could be masquerading as the powerful object thought to anchor our galaxy, explaining both the blistering speeds of stars near the ...
Feb. 7, 2026 Scientists have cracked a key mystery behind spider silk’s legendary strength and flexibility. They discovered that tiny molecular interactions act like natural glue, holding silk proteins together ...
Feb. 5, 2026 Physicists have watched a quantum fluid do something once thought almost impossible: stop moving. In experiments with ultra-thin graphene, researchers observed a superfluid—normally defined by its ...
Feb. 3, 2026 Astronomers have produced the most detailed map yet of dark matter, revealing the invisible framework that shaped the Universe long before stars and galaxies formed. Using powerful new observations ...
Feb. 3, 2026 A newly detected gravitational wave, GW250114, is giving scientists their clearest look yet at a black hole collision—and a powerful way to test ...
Feb. 2, 2026 MACE is a next-generation experiment designed to catch muonium transforming into its antimatter twin, a process that would rewrite the rules of particle physics. The last search for this effect ended ...
Jan. 31, 2026 nside electrochemical devices, strong electric fields dramatically alter how water molecules behave. New research shows that these fields speed up water dissociation not by lowering energy costs, but ...
Jan. 26, 2026 Physicists have discovered that hidden magnetic order plays a key role in the pseudogap, a puzzling state of matter that appears just before certain materials become superconductors. Using an ...
Jan. 26, 2026 For years, scientists noticed that magnetic fields could improve steel, but no one knew exactly why. New simulations reveal that magnetism changes how iron atoms behave, making it harder for carbon ...
Jan. 26, 2026 When materials become just one atom thick, melting no longer follows the familiar rules. Instead of jumping straight from solid to liquid, an unusual in-between state emerges, where atomic positions ...