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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

September 12, 2025

For the first time, scientists have observed electrons in graphene behaving like a nearly perfect quantum fluid, challenging a long-standing puzzle in physics. By creating ultra-clean samples, the team at IISc uncovered a surprising decoupling of ...
Physicists have unveiled a new superconducting detector sensitive enough to hunt dark matter particles smaller than electrons. By capturing faint photon signals, the device pushes the search into uncharted ...
Researchers in Germany and Australia have created a simple but powerful tool to detect nanoplastics—tiny, invisible particles that can slip through skin and even the blood-brain barrier. Using an "optical sieve" test strip viewed under a regular ...
Artificial intelligence is consuming enormous amounts of energy, but researchers at the University of Florida have built a chip that could change everything by using light instead of electricity for a core AI function. By etching microscopic lenses ...
Scientists at the University of Tokyo have unveiled “gold quantum needles,” a newly discovered nanocluster structure formed under unusual synthesis conditions. Unlike typical spherical clusters, these elongated, pencil-shaped formations display ...
Scientists have created a transparent solar coating that turns ordinary windows into clean energy generators without affecting clarity. Using cholesteric liquid crystal layers, the coating redirects polarized sunlight to the window edges where solar ...
A hidden quantum geometry that distorts electron paths has finally been observed in real materials. This “quantum metric,” once thought purely theoretical, may revolutionize electronics, superconductivity, and ultrafast ...
A Japanese research team successfully harnessed E. coli to produce PDCA, a strong, biodegradable plastic alternative. Their method avoids toxic byproducts and achieves record production levels, overcoming key roadblocks with creative ...
Scientists at Northwestern University have developed a groundbreaking nickel-based catalyst that could transform the way the world recycles plastic. Instead of requiring tedious sorting, the catalyst selectively breaks down stubborn polyolefin ...
Scientists in Japan have uncovered a strange new behavior in “heavy” electrons — particles that act as if they carry far more mass than usual. These electrons were found to be entangled, sharing a deep quantum link, and doing so in ways tied ...
Quantum scientists in Innsbruck have taken a major leap toward building the internet of the future. Using a string of calcium ions and finely tuned lasers, they created quantum nodes capable of generating streams of entangled photons with 92% ...
Rice University physicists confirmed that flat electronic bands in kagome superconductors aren’t just theoretical, they actively shape superconductivity and magnetism. This breakthrough could guide the design of next-generation quantum materials ...

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