Lifeboat Foundation

Abstract We have analytically determined the refractive index for the mechanical refraction of a relativistic particle for its all possible speeds. We have critically analysed the importance of Descartes’ metaphysical theory and extended it in this regard. We have considered the conservation of the tangential component of the relativistic momentum and the relativistic energy of the particle in the process of the mechanical refraction within the optical-mechanical analogy. Our result for the mechanical refractive index exactly matches with the forms of both the Fermat’s result on Snell’s law of optical refraction at the ultra-relativistic limit and the Descartes’ metaphysical result on the pseudo-Snell law of optical refraction at the non-relativistic limit. Graphic abstract Mechanical refraction from medium-1 to medium-2 for $$U2U1$$ U 2 U 1.

An international joint research team led by the Photonic Network Laboratory of Japan’s National Institute of Information and Communications Technology (NICT) has demonstrated a record-breaking aggregate optical transmission bandwidth of 37.6 THz to enable a new data-rate record of 402 terabits per second in a standard commercially available optical fiber.

This record was achieved by constructing the first optical transmission system covering all the transmission bands (OESCLU) of the low-loss window of standard optical fibers. The system combined various amplification technologies, some developed for this demonstration, including six kinds of doped fiber optical amplifiers and both discrete and distributed Raman amplification.

Novel optical gain equalizers also allowed access to new wavelength bands that are not yet utilized in deployed systems. The newly developed technology is expected to make a significant contribution to expanding the communication capacity of the optical communication infrastructure as future data services rapidly increase demand.

Most of us are familiar with the classic example of a liquid-gas moving contact line on a solid surface: a raindrop, sheared by the wind, creeps along a glass windscreen. The contact line’s movements depend on the interplay between viscous and surface tension forces—a relationship that has been thoroughly investigated in experimental fluid mechanics.

In a study published in The European Physical Journal Special Topics, Harish Dixit, of the Indian Institute of Technology Hyderabad, and his colleagues now examine the movements of a contact line formed at the interface between two immiscible liquids and a solid. The experiments fill a gap in fluid dynamics and suggest a mechanism for an imposed boundary condition that eludes mathematical description.

According to theory, the movement of a liquid-liquid contact line should be governed entirely by the liquids’ viscosity ratio and the angle at which the liquid interface meets the solid. To examine this in a real-world system, Dixit and his colleagues filled a rectangular tank with two liquid layers—silicone oil atop sugar water—with similar densities but significantly different viscosities. The researchers placed a glass slide at the edge of the tank, which they could slide vertically to create a moving contact line.

Advanced Materials, one of the world’s most prestigious journals, is the home of choice for best-in-class materials science for more than 30 years.

Two asteroids, including the newly detected 2024 MK, will pass Earth safely this week, coinciding with Asteroid Day. The event highlights efforts such as ESA’s asteroid deflection mission and their new Flyeye telescope system aimed at improving our detection and response to these celestial threats.

Two large asteroids will safely pass Earth this week, a rare occurrence perfectly timed to commemorate this year’s Asteroid Day. Neither poses any risk to our planet, but one of them was only discovered a week ago, highlighting the need to continue improving our ability to detect potentially hazardous objects in our cosmic neighborhood.

Research teams have successfully regenerated mouse brain circuits using rat stem cells, showcasing a new method for restoring brain function and studying interspecies brain development.

These findings open up possibilities for treating neurological diseases and understanding brain evolution, while also hinting at future clinical applications and ethical challenges in using similar techniques for human organ transplantation.

Scientists regenerate neural pathways in mice with cells from rats.

Researchers have developed a novel mechanical computer inspired by kirigami, utilizing interconnected polymer cubes for data storage without electronics.

This system allows for multiple stable states, enhancing binary computing to potentially include additional data states. The design, leveraging the principles of kirigami, enables complex data storage and computation structures with practical applications in mechanical encryption and haptic systems.

Mechanical Computing Innovation

MIT researchers have used simulations to suggest that the shorelines of Titan, Saturn ’s largest moon, are shaped by waves. This finding builds on images from NASA ’s Cassini spacecraft, which first confirmed the existence of Titan’s methane and ethane bodies. Understanding how these waves might erode the coastlines could offer insights into Titan’s climate and future sea evolution.

Titan’s Unique Extraterrestrial “Waters”

Titan, Saturn’s largest moon, is the only other planetary body in the solar system that currently hosts active rivers, lakes, and seas. These otherworldly river systems are thought to be filled with liquid methane and ethane that flows into wide lakes and seas, some as large as the Great Lakes on Earth.

A recent study has uncovered that a major earthquake around 2,500 years ago significantly rerouted the Ganges River in Bangladesh, marking the first documented instance of seismic activity causing a river avulsion. This discovery highlights the ongoing geological risks in delta regions, which could impact millions of people if repeated today. Credit: SciTechDaily.com.

A recent study published in Nature Communications reveals that a massive earthquake 2,500 years ago dramatically shifted the course of one of the world’s largest rivers. This previously undocumented seismic event rerouted the main channel of the Ganges River into present-day, densely populated Bangladesh, an area that continues to be at high risk for significant earthquakes.

Scientists have documented many river-course changes, called avulsions, including some in response to earthquakes. However, “I don’t think we have ever seen such a big one anywhere,” said study coauthor Michael Steckler, a geophysicist at Lamont-Doherty Earth Observatory, which is part of the Columbia Climate School. It could have easily inundated anyone and anything in the wrong place at the wrong time, he said.