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
September 12, 2025
Sep. 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 ...
Sep. 10, 2025 — 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 ...
Sep. 10, 2025 — 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 ...
Sep. 9, 2025 — 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 ...
Sep. 5, 2025 — 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 ...
Sep. 5, 2025 — 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 ...
Sep. 5, 2025 — 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 ...
Sep. 4, 2025 — 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 ...
Sep. 3, 2025 — 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 ...
Sep. 2, 2025 — 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 ...
Aug. 29, 2025 — 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% ...
Aug. 29, 2025 — 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 ...
Latest Headlines
updated 12:56 pm ET
Sep. 12, 2025 — For centuries, people believed ice was slippery because pressure and friction melted a thin film of water. But new research from Saarland University reveals that this long-standing explanation is ...
Sep. 12, 2025 — Scientists have, for the first time, successfully studied liquid carbon in the lab by combining a powerful high-performance laser with the European XFEL x-ray laser. The experiment captured fleeting ...
Sep. 12, 2025 — Gravitational-wave astronomy has exploded since 2015, capturing hundreds of black hole and neutron star collisions. With ever-clearer signals, researchers are testing Einstein’s relativity and ...
Sep. 11, 2025 — Physicists may soon witness a cosmic fireworks show: the explosive death of a primordial black hole. Once thought to be unimaginably rare, new research suggests there’s up to a 90% chance of ...
Sep. 9, 2025 — Saturn’s icy moon Enceladus has long fascinated scientists with its spectacular water plumes, which NASA’s Cassini spacecraft once revealed to contain organic molecules. Many hoped these ...
Sep. 7, 2025 — Physicists at the University of Colorado Boulder have created the first time crystal that humans can actually see, using liquid crystals that swirl into never-ending patterns when illuminated by ...
Sep. 4, 2025 — Scientists at Delft University of Technology have managed to watch a single atomic nucleus flip its magnetic state in real time. Using a scanning tunneling microscope, they indirectly read the ...
Aug. 31, 2025 — Astronomers at the University of Missouri, using the James Webb Space Telescope, have uncovered 300 unusually bright cosmic objects that may be some of the earliest galaxies ever formed. By applying ...
Aug. 29, 2025 — A Vermont research team has cracked a 90-year-old puzzle, creating a quantum version of the damped harmonic oscillator. By reformulating Lamb’s classical model, they showed how atomic vibrations ...
Aug. 28, 2025 — In just one afternoon, scientists used a nanoparticle “megalibrary” to find a catalyst that matches or exceeds iridium’s performance in hydrogen fuel production, at a fraction of the ...