Reference Terms
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Atom
In chemistry and physics, an atom is the smallest particle of a chemical element that retains its chemical properties. An atom consists of a dense nucleus of positively-charged protons and electrically-neutral neutrons, surrounded by a much larger electron cloud consisting of negatively-charged electrons. An atom is electrically neutral if it has the same number of protons as electrons. The number of protons in an atom defines the chemical element to which it belongs, while the number of neutrons determines the isotope of the element.
The first nuclei, including most of the helium and all of the deuterium in the universe, were theoretically created during big bang nucleosynthesis, about 3 minutes after the big bang. The first atoms were theoretically created 380,000 years after the big bang, an epoch called recombination, when the universe cooled to allow electrons to become attached to nuclei. Since then, atoms have been combined in stars through the process of nuclear fusion to generate atoms up to Iron.
A human hair is about 1 million carbon atoms wide.
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Matter & Energy News
August 27, 2025
Aug. 27, 2025 — Researchers have developed a blueprint for weaving hopfions—complex, knot-like light structures—into repeating spacetime crystals. By exploiting two-color beams, they can generate ordered chains and lattices with tunable topology, potentially ...
Aug. 27, 2025 — Researchers in Germany have unveiled the Metafiber, a breakthrough device that allows ultra-precise, rapid, and compact control of light focus directly within an optical fiber. Unlike traditional ...
Aug. 27, 2025 — Hydrogen fuel cells could power cars, devices, and homes with nothing but water as a byproduct—but platinum’s cost holds them back. Chinese researchers have now unveiled a breakthrough iron-based catalyst that could rival platinum while boosting ...
Aug. 26, 2025 — A research team created a plant-inspired molecule that can store four charges using sunlight, a key step toward artificial photosynthesis. Unlike past attempts, it works with dimmer light, edging closer to real-world solar fuel ...
Aug. 26, 2025 — Scientists have cracked one of chemistry’s toughest challenges with indoles, using copper to unlock a spot once thought too stubborn to change. The discovery could pave the way for easier, cheaper ...
Aug. 25, 2025 — Scientists using Google’s quantum processor have taken a major step toward unraveling the deepest mysteries of the universe. By simulating fundamental interactions described by gauge theories, the ...
Aug. 25, 2025 — Physicists have built a novel superconducting platform that mimics hidden vortex states once thought unobservable. Their "backdoor" method overcomes experimental limits, letting them control quantum behavior on demand. The discovery could pave the ...
Aug. 25, 2025 — Scientists have discovered that electron spin loss, long considered waste, can instead drive magnetization switching in spintronic devices, boosting efficiency by up to three times. The scalable, semiconductor-friendly method could accelerate the ...
Aug. 25, 2025 — Researchers cracked the mystery of altermagnets, materials with no net magnetization yet strange light-reflecting powers, by creating a new optical measurement method. Their findings confirmed altermagnetism in an organic crystal and opened doors to ...
Aug. 24, 2025 — A Rochester team engineered a new type of solar thermoelectric generator that produces 15 times more power than earlier versions. By enhancing heat absorption and dissipation rather than tweaking semiconductor materials, they dramatically improved ...
Aug. 24, 2025 — Ripple bugs’ fan-like legs inspired engineers to build the Rhagobot, a tiny robot with self-morphing fans. By mimicking these insects’ passive, ultra-fast movements, the robot gains speed, control, and endurance without extra ...
Aug. 24, 2025 — Scientists have developed a groundbreaking cryo-optical microscopy technique that freezes living cells mid-action, capturing ultra-detailed snapshots of fast biological processes. By rapidly immobilizing cells at precise moments, researchers can ...
Latest Headlines
updated 12:56 pm ET
Aug. 26, 2025 — Deep beneath southern China, JUNO has launched one of the most ambitious neutrino experiments in history. With its massive 20,000-ton liquid ...
Aug. 25, 2025 — Scientists at CERN’s ATLAS experiment have uncovered compelling evidence of Higgs bosons decaying into muons, an incredibly rare event that could deepen our understanding of how particles acquire ...
Aug. 23, 2025 — By using quantum dots and smart encryption protocols, researchers overcame a 40-year barrier in quantum communication, showing that secure networks don’t need perfect hardware to outperform ...
Aug. 23, 2025 — Researchers at the University of British Columbia have shown that a small bench-top reactor can enhance nuclear fusion rates by electrochemically loading a metal with deuterium fuel. Unlike massive ...
Aug. 23, 2025 — Researchers at Zhejiang University have found a way to stop performance-killing Auger recombination in perovskite lasers, using a clever additive during processing. Their method produced a ...
Aug. 23, 2025 — Scientists may have uncovered the missing piece of quantum computing by reviving a particle once dismissed as useless. This particle, called the neglecton, could give fragile quantum systems the full ...
Aug. 22, 2025 — Scientists are rethinking the universe’s deepest mysteries using numerical relativity, complex computer simulations of Einstein’s equations in extreme conditions. This method could help explore ...
Aug. 22, 2025 — Researchers developed a crystal that inhales and exhales oxygen like lungs. It stays stable under real-world conditions and can be reused many times, making it ideal for energy and electronic ...
Aug. 19, 2025 — Lithium battery recycling offers a powerful solution to rising demand, with discarded batteries still holding most of their valuable materials. Compared to mining, recycling slashes emissions and ...
Aug. 19, 2025 — A team in Milan has developed a first-of-its-kind single-atom catalyst that acts like a molecular switch, enabling cleaner, more adaptable chemical ...