Riverworld.
Imagine a world stretched along a single, endless river inside a colossal space megastructure. Explore the fascinating concept of the Topopolis, a futuristic habitat billions of miles long, where humanity might thrive in a sprawling civilization bound by physics, engineering, and imagination.
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/ discord Credits: Topopolis: The Eternal River Episode 487a; February 23, 2025 Written, Produced & Narrated by: Isaac Arthur Graphics: Apogii.uk, Ken York YD Visual, Steve Bowers, Udo Scroeter Select imagery/video supplied by Getty Images Music Courtesy of Epidemic Sound http://epidemicsound.com/creator.
The practice of purposely looping thread to create intricate knit garments and blankets has existed for millennia. Though its precise origins have been lost to history, artifacts like a pair of wool socks from ancient Egypt suggest it dates back as early as the third to fifth century CE. Yet, for all its long-standing ubiquity, the physics behind knitting remains surprisingly elusive.
“Knitting is one of those weird, seemingly simple but deceptively complex things we take for granted,” says theoretical physicist and visiting scholar at the University of Pennsylvania, Lauren Niu, who recently took up the craft as a means to study how “geometry influences the mechanical properties and behavior of materials.”
Despite centuries of accumulated knowledge, predicting how a particular knit pattern will behave remains difficult—even with modern digital tools and automated knitting machines. “It’s been around for so long, but we don’t really know how it works,” Niu notes. “We rely on intuition and trial and error, but translating that into precise, predictive science is a challenge.”
An international research collaboration led by the University of Surrey’s Nuclear Physics Group has overturned the long-standing belief that the atomic nucleus of lead-208 (²⁰⁸Pb) is perfectly spherical. The discovery challenges fundamental assumptions about nuclear structure and has far-reaching implications for our understanding of how the heaviest elements are formed in the universe.
Lead-208 is exceptionally stable due to being a “doubly magic” nucleus—and is the heaviest that we know of. However, a new study published in Physical Review Letters used a high-precision experimental probe to examine its shape and found that rather than being perfectly spherical, the nucleus of lead-208 is slightly elongated, resembling a rugby ball (prolate spheroid).
Dr. Jack Henderson, principal investigator of the study from the University of Surrey’s School of Mathematics and Physics, said, “We were able to combine four separate measurements using the world’s most sensitive experimental equipment for this type of study, which is what allowed us to make this challenging observation. What we saw surprised us, demonstrating conclusively that lead-208 is not spherical, as one might naively assume. The findings directly challenge results from our colleagues in nuclear theory, presenting an exciting avenue for future research.”
A supermassive black hole in the center of the Milky Way galaxy is creating a light show that’s intriguing astronomers.
Flares of light have been observed in a disk orbiting the black hole Sagittarius A*, according to a team of astrophysicists studying the black hole who published their findings Tuesday in The Astrophysical Journal Letters. Known as an accretion disk, it’s hot, contains a steady flow of materials like gas or plasma, and flickers constantly. The disks emit light that can be detected using infrared and X-ray instruments, which helps astronomers better observe the black holes the disks orbit.
A massive dataset of 3,628 Type Ia Supernovae from the Zwicky Transient Facility is being released, offering new insights into cosmic expansion.
This unprecedented collection will refine how cosmologists measure distances and study dark energy. With high-precision data from cutting-edge telescopes, scientists aim to resolve discrepancies in the standard cosmological model and explore new physics.
A Game-Changing Dataset for Cosmology.
Searching for life in alien oceans may be more difficult than scientists previously thought, even when we can sample these extraterrestrial waters directly.
A new study focusing on Enceladus, a moon of Saturn that sprays its ocean water into space through cracks in its icy surface, shows that the physics of alien oceans could prevent evidence of deep-sea life from reaching places where we can detect it.
Published today (Thursday, 6 February 2025) in Communications Earth and Environment, the study shows how Enceladus’s ocean forms distinct layers that dramatically slow the movement of material from the ocean floor to the surface.
A new discovery in physics and digital technology has identified a new magnetic phase that’s being called altermagnetism’ and it has incredible implications.
Traditional 3D printing builds objects layer by layer, but tomographic volumetric additive manufacturing (TVAM) takes a different approach. It uses laser light to illuminate a rotating vial of resin, solidifying material only where the accumulated energy surpasses a specific threshold. A key advantage of TVAM is its speed—it can produce objects in seconds, whereas conventional layer-based 3D printing takes about 10 minutes. However, its efficiency is a major drawback, as only about 1% of the projected light contributes to forming the intended shape.
Researchers from EPFL’s Laboratory of Applied Photonic Devices, led by Professor Christophe Moser, and the SDU Centre for Photonics Engineering, led by Professor Jesper Glückstad, have developed a more efficient TVAM technique, as reported in Nature Communications
<em> Nature Communications </em> is an open-access, peer-reviewed journal that publishes high-quality research from all areas of the natural sciences, including physics, chemistry, Earth sciences, and biology. The journal is part of the Nature Publishing Group and was launched in 2010. “Nature Communications” aims to facilitate the rapid dissemination of important research findings and to foster multidisciplinary collaboration and communication among scientists.
Most of us take it for granted that there are three dimensions, perhaps four if we count time. But for over 200 years, mathematicians and scientists have proposed further dimensions. In some standard versions of contemporary physics eleven dimensions are now proposed. But might the notion of additional dimensions be an empty idea that derails physics? Richard Feynman argued that proponents of extra dimensions.
A new adaptive optics technology is set to transform gravitational-wave detection, allowing LIGO
LIGO, or the Laser Interferometer Gravitational-Wave Observatory, is a large-scale physics experiment and observatory to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. There are two LIGO observatories in the United States—one in Hanford, Washington, and the other in Livingston, Louisiana. These observatories use laser interferometry to measure the minute ripples in spacetime caused by passing gravitational waves from cosmic events, such as the collisions of black holes or neutron stars.