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Big Bang nucleosynthesis
In physical cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than H-1, the normal, light hydrogen, during the early phases of the universe, shortly after the Big Bang. It is believed to be responsible for the formation of hydrogen (H-1 or simply H), its isotope deuterium (H-2 or D), the helium isotopes He-3 and He-4, and the lithium isotope Li-7. Big Bang nucleosynthesis begins about one minute after the Big Bang, when the universe has cooled enough to form stable protons and neutrons, after baryogenesis. From simple thermodynamical arguments, one can calculate the fraction of protons and neutrons based on the temperature at this point. This fraction is in favour of protons, because the higher mass of the neutron results in a spontaneous decay of neutrons to protons with a half-life of about 15 minutes.
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Space & Time News
December 15, 2025
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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 ...
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Nov. 21, 2025 New observations show that asteroid 1998 KY26 is a mere 11 meters across and spinning twice as fast as previously thought. The discovery adds complexity to Hayabusa2’s 2031 mission but also heightens scientific interest. The asteroid’s ...
Nov. 17, 2025 Scientists built a tiny clock from single-electron jumps to probe the true energy cost of quantum timekeeping. They discovered that reading the clock’s output requires vastly more energy than the clock uses to function. This measurement process ...
Nov. 16, 2025 Researchers combined deep learning with high-resolution physics to create the first Milky Way model that tracks over 100 billion stars individually. Their AI learned how gas behaves after supernovae, removing one of the biggest computational ...
Nov. 16, 2025 Dark matter may be invisible, but scientists are getting closer to understanding whether it follows the same rules as everything we can see. By comparing how galaxies move through cosmic gravity wells to the depth of those wells, researchers found ...
Nov. 13, 2025 Researchers engineered “gyromorphs,” a new type of metamaterial that combines liquid-like randomness with large-scale structural patterns to block light from every direction. This innovation solves longstanding limitations in quasicrystal-based ...
Nov. 13, 2025 Arctic sea ice is disappearing fast, and scientists have turned to an unexpected cosmic clue—space dust—to uncover how ice has changed over tens of thousands of years. By tracking helium-3–bearing dust trapped (or blocked) by ancient ice, ...
Nov. 10, 2025 New research from UBC Okanagan mathematically demonstrates that the universe cannot be simulated. Using Gödel’s incompleteness theorem, scientists found that reality requires “non-algorithmic understanding,” something no computation can ...
Nov. 2, 2025 A team of astronomers used the James Webb Space Telescope to create the first 3D atmospheric map of an exoplanet. The fiery WASP-18b, a massive “ultra-hot Jupiter,” revealed striking temperature contrasts, including regions so hot they destroy ...
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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. 15, 2025 Hot Jupiters were once cosmic oddities, but unraveling how they moved so close to their stars has remained a stubborn mystery. Scientists have long debated whether these giants were violently flung ...
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. 14, 2025 Webb’s latest observations reveal a hellish world cloaked in an unexpected atmosphere: TOI-561 b, an ultra-hot rocky planet racing around its star in under 11 hours. Despite being blasted by ...
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. 12, 2025 TRAPPIST-1e, an Earth-sized world in the system’s habitable zone, is drawing scientific attention as researchers hunt for signs of an atmosphere—and potentially life-supporting conditions. Early ...
Dec. 10, 2025 Uranus and Neptune may not be the icy worlds we’ve long imagined. A new Swiss-led study uses innovative hybrid modeling to reveal that these planets could just as easily be dominated by rock as by ...
Dec. 10, 2025 New research reveals that Earth’s solid inner core is actually in a superionic state, where carbon atoms flow freely through a solid iron lattice. This unusual behavior makes the core soft, ...
Dec. 10, 2025 Astronomers using the James Webb Space Telescope have captured dramatic helium streams pouring off the super-puff exoplanet WASP-107b, revealing a world with an enormously inflated, weakly bound ...
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