Lifeboat Foundation

And the g-forces???

Rockets being passé, China is working on using an electromagnetic railgun to launch crewed spacecraft the size of a Boeing 737, weighing 50 tonnes, into orbit. This remarkably ambitious project is even more ambitious than it seems at first glance.

Call it a railgun, a catapult, or a mass driver, the idea of replacing rockets with an electromagnetic accelerator is a very attractive option. Instead of lifting off on chemical rockets that have to carry fuel and fuel to lift the fuel and fuel to lift the fuel and the additional fuel, it makes more sense to keep as much of the launching system on the ground while leaving the vehicle as light as possible.

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In a novel experiment, physicists have observed long-range quantum coherence effects due to Aharonov-Bohm interference in a topological insulator-based device. This finding opens up a new realm of possibilities for the future development of topological quantum physics and engineering. This finding could also affect the development of spin-based electronics, which may potentially replace some current electronic systems for higher energy efficiency and may provide new platforms to explore quantum information science.

The research, published in Nature Physics, is the culmination of more than 15 years of work at Princeton. It came about when Princeton scientists developed a quantum device — called a bismuth bromide (α-Bi4Br4) topological insulator — only a few nanometers thick and used it to investigate quantum coherence.

Scientists have used topological insulators to demonstrate novel quantum effects for more than a decade. The Princeton team developed their bismuth-based insulator in a previous experiment where they demonstrated its effectiveness at room temperature. But this new experiment is the first time these effects have been observed with a very long-range quantum coherence and at a relatively high temperature. Inducing and observing coherent quantum states typically requires temperatures near absolute zero on artificially designed semiconducting materials only in the presence of strong magnetic fields.

Prof. Hagit Messer-Yaron from Tel Aviv University (TAU) is the recipient of the 2024 Institute of Electrical and Electronics Engineers (IEEE) medal for Environmental and Safety Technology for outstanding accomplishments in the application of technology in the fields of interest of IEEE that improve the environment and/or public safety. The award consists of a bronze medal, certificate, and cash honorarium.

Google presents DiPaCo v/@Ar_Douillard.

Distributed Path Composition.

An experimental mixture of experts that can be trained across the world, with no limit engineering-wise on its size, while being able to be light-weight and fast at test-time.

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The decision follows years of controversy and the departure of one of the program’s key researchers.

Researchers in the UC Davis Department of Biomedical Engineering are introducing a groundbreaking catheter-based device that could revolutionize heart attack and stroke prevention by enhancing intravascular imaging of dangerous plaques.

Researchers in the Department of Biomedical Engineering at the University of California, Davis, have developed a new catheter-based device that combines two powerful optical techniques to image the dangerous plaques that can build up inside the arteries that supply blood to the heart. By providing new details about plaque, the device could help clinicians and researchers improve treatments for preventing heart attacks and strokes.

Atherosclerosis occurs when fats, cholesterol and other substances accumulate on the artery walls, which can cause these vessels to become thick and stiff. A heart attack or stroke may occur if an atherosclerotic plaque inside the blood vessels ruptures or parts of it break off.

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We use two 1D quasicondensates in a double potential well to realize a bosonic Josephson junction, a microscopic system that gives rise to interesting quantum phenomena resulting from the interplay of quantum tunneling and interaction. The multimode characteristics within the quasicondensates make the system suitable as a quantum field simulator. To prepare quantum states, we split a single condensate into two and, consequently, we witness the dynamical evolution of quantum fluctuations in the relative degree of freedom between the two split condensates. We demonstrate how to use these dynamics to effectively prepare more strongly correlated quantum states and how those influence spatial phase coherence.

Our work introduces innovative methods for engineering correlations and entanglement in the external degree of freedom of interacting many-body systems. It is a leap forward in understanding and harnessing quantum correlations, paving the way for exciting possibilities in quantum simulation research.

The first thing many media seem not to understand is the methodology followed by Space X, which is completely different from what the traditional aerospace builders do. While the latter prefer to spend their money on a long project life cycle, including long requirements discussion, and meticulous and detailed test engineering and integration phases, Space X opts for a methodology closer to the experimental scientific method: draw essential requirements, build a prototype, test, fail, learn from failures, build a new improved prototype, and try again. Each reiteration adds quality to the project, up to a point when the prototype is working well, and Falcon 9 (as a sample) becomes the space workhorse with any more competitors in the world. Is that so hard to be understood, for journalists?When a traditional project fails, many billions are wasted, and many years of work are canceled. When a “normal” failure occurs during Space X’s reiterative project development, very less resources are wasted. And, after all, during the expendable rockets’ age, all the rockets were always wasted, at every launch! The difference is incomparable. Another advantage of this method is its high flexibility. If a project lasts 10 years, it is difficult to take advantage of the technological advances: switching to new technology in a project initiated many years ago forces heavy requirements reviews and unavoidable delays. In a fail-and-repeat project, new technologies and new ideas can be adopted more easily and more quickly, as demonstrated by the thousands of changes and improvements applied to the different starships, super-heavy boosters, and raptor engine prototypes throughout history. Despite the misfortune bearers and the envious, the methodology works. The success of Space X in the launchers market doesn’t lie.

Starship 28 and the Super-Heavy Booster 10 made most of the expected work, and even more than what was expected: while the suborbital altitude was planned, the Starship spacecraft reached 230 km, a low Earth orbit altitude at more than 26,200 km/h. several tests were conducted after the engine cutoff, including a propellant transfer demo and payload dispenser test.

Only two operations have failed. The booster couldn’t make it to descend vertically on its engines, since only 3 of them reignited, and splashed in the Mexican Gulf at little more than 1,000 km/h. The Starship failed during the re-entry in the atmosphere, in the Indian Ocean. We could observe many insulating tiles flying away from the Starship’s body during the first part of the re-entry. At an altitude of 65 km, telemetry from Ship 28 was lost, and the vehicle was destroyed before splashing in the sea.

Since November 2023, NASA’s Voyager 1 spacecraft has been sending a steady radio signal to Earth, but the signal does not contain usable data. The source of the issue appears to be with one of three onboard computers, the flight data subsystem (FDS), which is responsible for packaging the science and engineering data before it’s sent to Earth by the telemetry modulation unit.

On March 3, the Voyager mission team saw activity from one section of the FDS that differed from the rest of the computer’s unreadable data stream. The new signal was still not in the format used by Voyager 1 when the FDS is working properly, so the team wasn’t initially sure what to make of it. But an engineer with the agency’s Deep Space Network, which operates the radio antennas that communicate with both Voyagers and other spacecraft traveling to the Moon and beyond, was able to decode the new signal and found that it contains a readout of the entire FDS memory.

The FDS memory includes its code, or instructions for what to do, as well as variables, or values used in the code that can change based on commands or the spacecraft’s status. It also contains science or engineering data for downlink. The team will compare this readout to the one that came down before the issue arose and look for discrepancies in the code and the variables to potentially find the source of the ongoing issue.