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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

October 27, 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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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. ...

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