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Quantum number
A quantum number describes the energies of electrons in atoms. Each quantum number specifies the value of a conserved quantity in the dynamics of the quantum system. Since any quantum system can have one or more quantum numbers, it is a futile job to list all possible quantum numbers. The question of how many quantum numbers are needed to describe any given system has no universal answer, although for each system one must find the answer for a full analysis of the system. The most widely studied set of quantum numbers is that for a single electron in an atom: not only because it is useful in chemistry, being the basic notion behind the periodic table, valence (chemistry) and a host of other properties, but also because it is a solvable and realistic problem, and, as such, finds widespread use in textbooks.
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Matter & Energy News
December 19, 2025
Dec. 19, 2025 Gravitational waves from black holes may soon reveal where dark matter is hiding. A new model shows how dark matter surrounding massive black holes leaves detectable fingerprints in the waves recorded by future space ...
Dec. 15, 2025 Researchers in Sweden have unveiled a way to create high-performance electronic electrodes using nothing more than visible light and specially designed water-soluble monomers. This gentle, chemical-free approach lets conductive plastics form ...
Dec. 13, 2025 Researchers at the University of Warsaw have unveiled a breakthrough method for detecting and precisely calibrating terahertz frequency combs using a quantum antenna made from Rydberg atoms. By combining atomic electrometry with a powerful ...
Dec. 13, 2025 MOCHI uses microscopic, air-filled channels to stop heat in its tracks while remaining nearly crystal clear. If scaled up, it could transform windows into powerful energy savers and solar ...
Dec. 11, 2025 Scientists developed a high-performance hydrogen-production catalyst using lignin, a common waste product from paper and biorefinery processes. The nickel–iron oxide nanoparticles embedded in carbon fibers deliver fast kinetics, long-term ...
Dec. 6, 2025 SQUIRE aims to detect exotic spin-dependent interactions using quantum sensors deployed in space, where speed and environmental conditions vastly improve sensitivity. Orbiting sensors tap into ...
Dec. 5, 2025 Scientists have discovered how to electrically power insulating nanoparticles using organic molecules that act like tiny antennas. These hybrids generate extremely pure near-infrared light, ideal for medical diagnostics and advanced communications. ...
Dec. 5, 2025 Kyushu University scientists have achieved a major leap in fuel cell technology by enabling efficient proton transport at just 300°C. Their scandium-doped oxide materials create a wide, soft pathway that lets protons move rapidly without clogging ...
Dec. 5, 2025 Researchers engineered a strained germanium layer on silicon that allows charge to move faster than in any silicon-compatible material to date. This record mobility could lead to chips that run cooler, faster, and with dramatically lower energy ...
Dec. 4, 2025 Researchers have discovered a new way to grow graphene that deliberately adds structural defects to enhance its usefulness in electronics, sensors, catalysts, and more. Using a specially shaped molecule called azupyrene, scientists can produce ...
Dec. 2, 2025 A UC Irvine team uncovered a never-before-seen quantum phase formed when electrons and holes pair up and spin in unison, creating a glowing, liquid-like state of matter. By blasting a custom-made material with enormous magnetic fields, the ...
Dec. 1, 2025 Engineers have unlocked a new class of supercapacitor material that could rival traditional batteries in energy while charging dramatically faster. By redesigning carbon structures into highly curved, accessible graphene networks, the team achieved ...
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Dec. 18, 2025 After a decade of painstaking measurements, scientists have delivered a major plot twist in particle physics: a long-hypothesized “mystery particle” likely doesn’t exist. Using the MicroBooNE ...
Dec. 17, 2025 A long-standing physics mystery has been solved with the discovery of emergent photon-like behavior inside a strange quantum material. The finding confirms a true 3D quantum spin liquid and unlocks a ...
Dec. 16, 2025 Physicists have found a clever way to detect the elusive Unruh effect without extreme accelerations. By using atoms that emit light cooperatively between mirrors, acceleration subtly shifts when a ...
Dec. 15, 2025 A new theory proposes that the universe’s fundamental forces and particle properties may arise from the geometry of hidden extra dimensions. These dimensions could twist and evolve over time, ...
Dec. 14, 2025 Astronomers tracked a decade of dramatic changes in P13, a neutron star undergoing supercritical accretion. Its X-ray luminosity rose and fell by factors of hundreds while its rotation rate ...
Dec. 12, 2025 Scientists have managed to observe solar neutrinos carrying out a rare atomic transformation deep underground, converting carbon-13 into nitrogen-13 inside the SNO+ detector. By tracking two faint ...
Dec. 11, 2025 Scientists have uncovered that some atoms in liquids don't move at all—even at extreme temperatures—and these anchored atoms dramatically alter the way materials freeze. Using advanced electron ...
Dec. 8, 2025 A remarkably clean gravitational-wave detection has confirmed long-standing predictions about black holes, including Hawking’s area theorem and Einstein’s ringdown behavior. The findings also ...
Dec. 8, 2025 XRISM’s high-precision X-ray data revealed unusually strong signatures of chlorine and potassium inside the Cassiopeia A supernova remnant. These levels are far higher than theoretical models ...
Dec. 4, 2025 Penn State researchers created seven new high-entropy oxides by removing oxygen during synthesis, enabling metals that normally destabilize to form rock-salt ceramics. Machine learning helped ...