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 1, 2025
Aug. 1, 2025 — A Penn State-led research team has unraveled the long-standing mystery of how lightning begins inside thunderclouds. Their findings offer the first quantitative, physics-based explanation for lightning initiation—and a glimpse into the stormy ...
July 29, 2025 — Scientists have cracked open a mysterious layer inside batteries, using cutting-edge 3D atomic force microscopy to capture the dynamic molecular structures at their solid-liquid interfaces. These once-invisible electrical double layers (EDLs) twist, ...
July 29, 2025 — Deep beneath the Swiss-French border, the Large Hadron Collider unleashes staggering amounts of energy and radiation—enough to fry most electronics. Enter a team of Columbia engineers, who built ultra-rugged, radiation-resistant chips that now ...
July 29, 2025 — Researchers are exploring AI-powered digital twins as a game-changing tool to accelerate the clean energy transition. These digital models simulate and optimize real-world energy systems like wind, solar, geothermal, hydro, and biomass. But while ...
July 28, 2025 — Deep in Serbia's Jadar Valley, scientists discovered a mineral with an uncanny resemblance to Superman's Kryptonite both in composition and name. Dubbed jadarite, this dull white crystal lacks the ...
July 27, 2025 — A team at KAUST has revealed that the short lifespan of aqueous batteries is primarily due to "free water" molecules triggering harmful chemical reactions at the anode. By adding affordable sulfate salts like zinc sulfate, they significantly reduced ...
July 24, 2025 — Aalto University physicists in Finland have set a new benchmark in quantum computing by achieving a record-breaking millisecond coherence in a transmon qubit — nearly doubling prior limits. This development not only opens the door to far more ...
July 23, 2025 — Imagine concrete that not only survives wildfires and extreme weather, but heals itself and absorbs carbon from the air. Scientists at USC have created an AI model called Allegro-FM that simulates billions of atoms at once, helping design futuristic ...
July 20, 2025 — Scientists have used DNA's self-assembling properties to engineer intricate moiré superlattices at the nanometer scale—structures that twist and layer like never before. With clever molecular ...
July 19, 2025 — Scientists have cracked a century-old physics mystery by detecting magnetic signals in non-magnetic metals using only light and a revamped laser technique. Previously undetectable, these faint magnetic “whispers” are now measurable, revealing ...
July 17, 2025 — Using advanced metasurfaces, researchers can now twist light to uncover hidden images and detect molecular handedness, potentially revolutionizing data encryption, biosensing, and drug ...
July 16, 2025 — A powerful new technique harnesses swirling plasma inside laser-blasted microtubes to produce record-breaking magnetic fields—rivaling those near neutron stars—all within a compact laboratory setup. This innovation promises to transform ...
Latest Headlines
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Aug. 1, 2025 — At the edge of two exotic materials, scientists have discovered a new state of matter called a "quantum liquid crystal" that behaves unlike anything we've seen before. When a conductive Weyl ...
Aug. 1, 2025 — A tiny 3 kg detector has made a huge leap in neutrino science by detecting rare CEvNS interactions at a Swiss reactor. This elusive effect, long predicted and hard to measure, was captured with ...
July 28, 2025 — For the first time ever, scientists have watched electrons perform a bizarre quantum feat: tunneling through atomic barriers by not just slipping ...
July 28, 2025 — Neutrinos, ghostly particles barely interacting with matter, may secretly be reshaping the fates of massive stars. New research suggests that as stars collapse, they form natural "neutrino ...
July 28, 2025 — Penn State researchers have uncovered a surprising twist in a foundational chemical reaction known as oxidative addition. Typically believed to involve transition metals donating electrons to organic ...
July 28, 2025 — Scientists at OIST have defied a foundational rule in chemistry by creating a stable 20-electron version of ferrocene—an organometallic molecule once thought to be limited to 18 valence electrons. ...
July 26, 2025 — A pioneering team at the University of Maryland has captured the first-ever images of atomic thermal vibrations, unlocking an unseen world of motion within two-dimensional materials. Their innovative ...
July 22, 2025 — Scientists have observed a brand-new and exotic atomic nucleus: aluminium-20. Unlike anything seen before, it decays through a stunning three-proton emission sequence, shedding light on nuclear ...
July 22, 2025 — Scientists at Rice University and the University of Houston have created a powerful new material by guiding bacteria to grow cellulose in aligned ...
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