Lifeboat Foundation

Waste heat produced by solar cells undermines their performance, but the race is on to harness it for useful purposes. Researchers have found a way to tap into that heat to collect water out of the air, and have demonstrated the effectiveness of the idea by growing spinach in the Arabian desert, one of the driest places on Earth.

Stephen has a science degree with a major in physics, an arts degree with majors in English Literature and History and Philosophy of Science and a Graduate Diploma in Science Communication.

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A new Webb Space Telescope image of the bright, nearby star Fomalhaut reveals details never seen before, including nested rings of dust that hint at the forces of unseen planets.

A team led by University of Arizona astronomers used NASA

Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. Its vision is “To discover and expand knowledge for the benefit of humanity.” Its core values are “safety, integrity, teamwork, excellence, and inclusion.” NASA conducts research, develops technology and launches missions to explore and study Earth, the solar system, and the universe beyond. It also works to advance the state of knowledge in a wide range of scientific fields, including Earth and space science, planetary science, astrophysics, and heliophysics, and it collaborates with private companies and international partners to achieve its goals.

Update: The image for the ChatGPT 3.5 and vicuna-13B comparison has been updated for readability.

With the launch of Large Language Models (LLMs) for Generative Artificial Intelligence (GenAI), the world has become both enamored and concerned with the potential for AI. The ability to hold a conversation, pass a test, develop a research paper, or write software code are tremendous feats of AI, but they are only the beginning to what GenAI will be able to accomplish over the next few years. All this innovative capability comes at a high cost in terms of processing performance and power consumption. So, while the potential for AI may be limitless, physics and costs may ultimately be the boundaries.

Tirias Research forecasts that on the current course, generative AI data center server infrastructure plus operating costs will exceed $76 billion by 2028, with growth challenging the business models and profitability of emergent services such as search, content creation, and business automation incorporating GenAI. For perspective, this cost is more than twice the estimated annual operating cost of Amazon’s cloud service AWS, which today holds one third of the cloud infrastructure services market according to Tirias Research estimates. This forecast incorporates an aggressive 4X improvement in hardware compute performance, but this gain is overrun by a 50X increase in processing workloads, even with a rapid rate of innovation around inference algorithms and their efficiency. Neural Networks (NNs) designed to run at scale will be even more highly optimized and will continue to improve over time, which will increase each server’s capacity. However, this improvement is countered by increasing usage, more demanding use cases, and more sophisticated models with orders of magnitude more parameters. The cost and scale of GenAI will demand innovation in optimizing NNs and is likely to push the computational load out from data centers to client devices like PCs and smartphones.

The idea of ‘absolute time’ is an illusion. Physics and subjective experience reveal why.

A spinning plasma ring mimics the rotating structure surrounding a black hole.

Astrophysicists have many questions about the so-called accretion disk that forms from plasma and other matter falling into a black hole. Now researchers have generated a rotating ring of plasma in an unconfined arrangement in the lab, which will enable more realistic studies of plasma in astrophysical disks [1]. The lab plasma also produced a jet perpendicular to the disk, as real black holes do. The experiment could provide a platform for testing theories describing the evolution of astrophysical disks.

According to observations, the matter in a black hole accretion disk spirals inward at a rate that is thousands of times faster than would be expected from turbulence-free rotation. The leading explanation involves turbulence generated in part by the interaction of magnetic fields with the plasma in the disk, but this theory is difficult to test without a lab plasma that rotates rapidly. Such an experimental system would also allow researchers to investigate accretion disks around massive objects other than black holes.

Scientists from Jilin University, the Center for High Pressure Science and Technology Advanced Research, and Skoltech have synthesized lanthanum-cerium polyhydride, a material that promises to facilitate studies of near-room-temperature superconductivity. It offers a compromise between the polyhydrides of lanthanum and cerium in terms of how much cooling and pressure it requires. This enables easier experiments, which might one day lead scientists to compounds that conduct electricity with zero resistance at ambient conditions—an engineering dream many years in the making. The study was published in Nature Communications.

One of the most intriguing unsolved questions in modern physics is: Can we make a material that conducts electricity with zero resistance (superconducts) at room temperature and atmospheric pressure? Such a superconductor would enable power grids with unprecedented efficiency, ultrafast microchips, and electromagnets so powerful they could levitate trains or control fusion reactors.

In their search, scientists are probing multiple classes of materials, slowly nudging up the temperature they superconduct at and decreasing the pressure they require to remain stable. One such group of materials is polyhydrides—compounds with extremely high hydrogen content. At −23°C, the current champion for high-temperature superconductivity is a lanthanum polyhydride with the formula LaH₁₀. The trade-off: It requires the pressure of 1.5 million atmospheres. At the opposite end of the spectrum, cuprates are a class of materials that superconduct under normal atmospheric pressure but require cooler temperatures —no more than −140°.

Most of Mars appears to be an endless expanse of alien desert, without a river or lake in sight. However, liquid water definitely existed in the planet’s distant past. A new paper has also suggested that it’s also possible small quantities of water still might exist in places that otherwise appear barren.

Before China’s Zhurong (also known as Phoenix) rover went into hibernation mode last May, researchers from the National Astronomical Observatories and the Institute of Atmospheric Physics of the Chinese Academy of Sciences discovered something unexpected. Zhurong was exploring the Utopia Planitia region, which is near the planet’s equator. No liquid water was thought to exist at those latitudes. Yet when the rover beamed back data from its Multispectral Camera (MSCam), Navigation and Terrain Camera (NaTeCam), and Mars Surface Composition Detector (MarSCoDe), there was possible evidence for liquid water having been present less than half a million years ago.

“[Our findings] suggest [features] associated with the activity of saline water, indicating the existence of water process on the low-latitude region of Mars,” the researchers said in a study recently published in Science Advances.

This breakthrough opens doors to investigating the early universe independent of traditional cosmic background radiation studies.

Unveiling the mysteries of the universe’s earliest moments has always been a tantalizing pursuit for scientists and cosmologists. And now, a team of researchers has made a groundbreaking discovery that promises to shed new light on these enigmatic beginnings.

In a study published in Physical Review Letters on May 2, scientists uncovered a new approach to exploring the dynamics of the early universe using gravitational waves.