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
October 25, 2025
Oct. 25, 2025 — A UCLA-led team has achieved the sharpest-ever view of a distant star’s disk using a groundbreaking photonic lantern device on a single telescope—no multi-telescope array required. This technology splits incoming starlight into multiple ...
Oct. 25, 2025 — Researchers propose that hydrogen gas from the early Universe emitted detectable radio waves influenced by dark matter. Studying these signals, especially from the Moon’s radio-quiet environment, could reveal how dark matter clumped together ...
Oct. 24, 2025 — A team of researchers has designed a theoretical model for a topological quantum battery capable of long-distance energy transfer and immunity to dissipation. By exploiting topological properties in photonic waveguides, they showed that energy loss ...
Oct. 23, 2025 — Scientists have developed a chromium-molybdenum-silicon alloy that withstands extreme heat while remaining ductile and oxidation-resistant. It could replace nickel-based superalloys, which are limited to about 1,100°C. The new material might make ...
Oct. 21, 2025 — Researchers have found that 2D materials can self-form microscopic cavities that trap light and electrons, altering their quantum behavior. With a miniaturized terahertz spectroscope, the team observed standing light-matter waves without needing ...
Oct. 20, 2025 — A new light-driven cancer therapy uses LEDs and tin nanoflakes to kill tumors safely and affordably. Developed by teams in Texas and Portugal, it eliminates up to 92% of skin cancer cells without ...
Oct. 19, 2025 — Researchers from NTNU and EPFL have unveiled a compact, low-cost laser that outperforms current models in speed, control, and precision. Built using microchip technology, it can be mass-produced for use in everything from Lidar navigation to gas ...
Oct. 18, 2025 — A collaboration between the University of Michigan and AFRL has resulted in 3D-printed metamaterials that can block vibrations using complex geometries. Inspired by nature and theoretical physics, these “kagome tubes” demonstrate how geometry ...
Oct. 17, 2025 — Researchers discovered how to stabilize a high-performance sodium compound, giving sodium-based solid-state batteries the power and stability they’ve long lacked. The new material conducts ions far ...
Oct. 11, 2025 — A team of engineers at North Carolina State University has designed a polymer “Chinese lantern” that can rapidly snap into multiple stable 3D shapes—including a lantern, a spinning top, and more—by compression or twisting. By adding a ...
Oct. 11, 2025 — Scientists have developed an ultra-thin, paper-like LED that emits a warm, sunlike glow, promising to revolutionize how we light up our homes, devices, and workplaces. By engineering a balance of red, yellow-green, and blue quantum dots, the ...
Oct. 10, 2025 — Scientists at EPFL have reimagined 3D printing by turning simple hydrogels into tough metals and ceramics. Their process allows multiple infusions of metal salts that form dense, high-strength structures without the porosity of earlier methods. ...
Latest Headlines
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Oct. 24, 2025 — Researchers in Konstanz discovered a way to manipulate materials with light by exciting magnon pairs, reshaping their magnetic “fingerprint.” This allows non-thermal control of magnetic states ...
Oct. 23, 2025 — Chalmers researchers have developed a simple, light-based platform to study the mysterious “invisible glue” that binds materials at the nanoscale. Gold flakes floating in salt water reveal how ...
Oct. 23, 2025 — Researchers suggest that dark matter might subtly color light red or blue as it passes through, revealing traces of its existence. Using a network-like model of particle connections, they argue that ...
Oct. 22, 2025 — Under the sea, green algae have evolved a clever way to handle too much sunlight. Scientists found that a special pigment called siphonein acts like a natural sun shield, protecting the algae’s ...
Oct. 21, 2025 — Physicists have uncovered the fascinating world of “rotating crystals” — solids made of spinning particles that behave in strange, almost ...
Oct. 18, 2025 — Researchers have unveiled a new model for the universe’s birth that replaces cosmic inflation with gravitational waves as the driving force behind creation. Their simulations show that gravity and ...
Oct. 16, 2025 — Auburn scientists have designed new materials that manipulate free electrons to unlock groundbreaking applications. These “Surface Immobilized Electrides” could power future quantum computers or ...
Oct. 15, 2025 — Scientists at TU Wien have uncovered that quantum correlations can stabilize time crystals—structures that oscillate in time without an external driver. Contrary to previous assumptions, quantum ...
Oct. 15, 2025 — Researchers analyzing pulsar data have found tantalizing hints of ultra-slow gravitational waves. A team from Hirosaki University suggests these signals might carry “beats” — patterns formed by ...
Oct. 15, 2025 — Scientists at the University of Cambridge have uncovered a surprising quantum effect inside an organic material, something once thought impossible outside metals. The team found that a special ...