From pocket-sized AI models to a warp drive breakthrough, check out this week’s awesome tech stories from around the web.
While tantalizing, Alcubierre’s design has a fatal flaw. To provide the necessary distortions of spacetime, the spacecraft must contain some form of exotic matter, typically regarded as matter with negative mass. Negative mass has some conceptual problems that seem to defy our understanding of physics, like the possibility that if you kick a ball that weighs negative 5 kilograms, it will go flying backwards, violating conservation of momentum. Plus, nobody has ever seen any object with negative mass existing in the real universe, ever.
These problems with negative mass have led physicists to propose various versions of “energy conditions” as supplements to general relativity. These aren’t baked into relativity itself, but add-ons needed because general relativity allows things like negative mass that don’t appear to exist in our universe—these energy conditions keep them out of relativity’s equations. They’re scientists’ response to the unsettling fact that vanilla GR allows for things like superluminal motion, but the rest of the universe doesn’t seem to agree.
The energy conditions aren’t experimentally or observationally proven, but they are statements that concord with all observations of the universe, so most physicists take them rather seriously. And until recently, physicists have viewed those energy conditions as making it absolutely 100 percent clear that you can’t build a warp drive, even if you really wanted to.
New solar observations indicate that plasma waves are responsible for the Sun’s outer atmosphere having different abundances of chemical elements than the Sun’s other layers.
The solar corona is a halo of hot, tenuous plasma that surrounds the Sun out to large distances. It is visible during solar eclipses (Fig. 1) but is usually outshone by the glare of the Sun’s surface, or photosphere. The corona has different abundances of chemical elements than the rest of the Sun, and a longstanding question has been why this disparity exists. New solar measurements by Mariarita Murabito at the Italian National Institute of Astrophysics (INAF) and colleagues suggest that the difference is caused by plasma waves dragging easily ionized elements from the Sun’s lower atmosphere into the corona [1]. This finding could lead to a better understanding of the structure of stars.
The corona is of great interest to solar physicists, partly because it produces the solar wind—an outflow of hot gas from the Sun. The solar wind is most evident to us on Earth when its particles become trapped in Earth’s magnetic field and collide with our atmosphere, causing an aurora. An important problem in solar physics is to determine which coronal structures generate the solar wind and how solar conditions affect the outflow’s properties. The elemental composition of the solar wind sheds light on its origins, as this composition does not change once the gas leaves the Sun. The solar wind can be directly sampled by spacecraft in situ, and its elemental abundances can be compared to coronal abundances inferred from spectroscopy.
Scientists have made a significant breakthrough in understanding the properties of promethium, a rare earth element with elusive characteristics despite its use in modern technology.
Researchers have uncovered the properties of a rare earth element that was first discovered 80 years ago at the very same laboratory. Their discoveries open a new pathway for the exploration of elements critical in modern technology, from medicine to space travel.
Continue reading “Promethium Discovery Set to Rewrite Chemistry Textbooks” »
In a stunning scientific feat in the field of cryonics, a team from Fudan University in Shanghai achieved a monumental breakthrough by successfully reviving a human brain that had been frozen for as long as 18 months. This record breaking achievement not only shatters previous records in cryogenic technology but has also been published in the esteemed academic journal Cell Reports Methods.
The team led by Shao Zhicheng created a revolutionary cryopreservation method, dubbed MEDY, which preserves the structural integrity and functionality of neural cells, allowing for the preservation of various brain tissues and human brain specimens. This advancement holds immense promise not only for research into neurological disorders but also opens up possibilities for the future of human cryopreservation technology.
Professor Joao Pedro Magalhaes from the University of Birmingham K expressed profound astonishment at the development, hailing the technology’s ability to prevent cell death and help preserve neural functionality as nothing short of miraculous. He speculated that in the future, terminally ill patients could be cryopreserved, awaiting cures that may emerge, while astronauts could be frozen for interstellar travel, awakening in distant galaxies.
SpaceX has made significant advancements in the development and testing of the Starship rocket, with successful modifications, testing, and potential future launches without a license, as well as progress in the Falcon 9 rocket and challenges faced by ULA’s Vulcan Centaur Questions to inspire discussion What updates ha.
The NASA/ESA/CSA James Webb Space Telescope has captured the sharpest infrared images to date of one of the most distinctive objects in our skies, the Horsehead Nebula. These observations show a part of the iconic nebula in a whole new light, capturing its complexity with unprecedented spatial resolution.
Webb’s new images show part of the sky in the constellation Orion (The Hunter), in the western side of the Orion B molecular cloud. Rising from turbulent waves of dust and gas is the Horsehead Nebula, otherwise known as Barnard 33, which resides roughly 1,300 light-years away.
The nebula formed from a collapsing interstellar cloud of material, and glows because it is illuminated by a nearby hot star. The gas clouds surrounding the Horsehead have already dissipated, but the jutting pillar is made of thick clumps of material that is harder to erode. Astronomers estimate that the Horsehead has about 5 million years left before it too disintegrates. Webb’s new view focuses on the illuminated edge of the top of the nebula’s distinctive dust and gas structure.
The transcript features an interview with renowned science fiction author Isaac Asimov, discussing his predictions and visions for the future of space exploration, computers, robotics, and humanity’s role in shaping that future. It touches on concepts like permanent space settlements, harnessing solar power, the increasing importance of computers and AI, the impacts of robotics on jobs, and taking an optimistic yet cautionary view of technological progress. It also covers some earlier inaccurate and exaggerated predictions about robots replacing humans, as well as actual technological developments in 1982 like artificial hearts and fusion reactors. The overall theme is Asimov’s hopeful but measured outlook on future scientific and technological advancements.
Photo : siqi zhao & huirong yan.
Astrophysicists from the University of Potsdam have made a significant step toward solving the last puzzle in magnetohydrodynamic turbulence theory by observing the weak to strong transition in the space plasma turbulence surrounding Earth with newly developed multi-spacecraft analysis methods. Their pioneering discovery was published today in the journal Nature Astronomy.
Turbulence is ubiquitous in nature. It exists everywhere, from our daily lives to the distant universe, while being labelled as “the last great unsolved problem of classical physics” by Richard Feynman.
