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A British aerospace startup is working on a fusion rocket it says will slash the amount of time it takes astronauts to travel to Mars and beyond — allowing humans to explore places that are currently far out of reach.

The challenge: Long-term exposure to microgravity and cosmic radiation can cause serious health issues for astronauts. That means NASA needs to keep its future Mars missions short enough that astronauts come home healthy — less than 4 years should work.

Using our current rocket propulsion technology, though, it’s going to take seven months just to get astronauts to Mars. Factor in the amount of time to get back to Earth, and nearly a third of a Mars astronaut’s mission is just going to be dedicated to the commute.

A high-stakes battle is unfolding between major tech giants to create dominant “everything apps” that combine digital identity, messaging, payments, and AI services. The winner of this contest could gain unrivalled data to power their AI platforms and to shape the future of society.

There is the promise of implementing a universal basic income (UBI) via these super apps as a mechanism to mitigate the downside risks of technological disruption in an era of accelerating automation and the rise of artificial general intelligence. Whether the promises will be delivered, lead to more equality, be decentralized enough to distribute power to all of humanity, or be available in time before the automation disruption will be, at the very least, interesting to monitor.

The main contenders in this race are:

Microscopic materials made of clay, designed by researchers at the University of Missouri, could be key to the future of synthetic materials chemistry. By enabling scientists to produce chemical layers tailor-made to deliver specific tasks based on the goals of the individual researcher, these materials, called nanoclays, can be used in a wide variety of applications, including the medical field or environmental science.

A paper describing this research is published in the journal ACS Applied Engineering Materials.

A fundamental part of the material is its electrically charged surface, said Gary Baker, co-principal investigator on the project and an associate professor in the Department of Chemistry.

A scalable system for controlling quantum bits demonstrates a very low error rate, which is essential for making practical devices.

A major obstacle to the development of practical quantum computers is the difficulty of scaling up—making a device with large numbers of quantum bits (qubits) that also gives accurate results in the presence of environmental noise. Now researchers report a significant improvement in the accuracy of a technology that is already known to be much easier to scale up than conventional techniques [1]. This alternative technology uses units of magnetic flux called flux quanta to control conventional superconducting qubits. The reduction in the error rate came from physically separating the control circuits from the qubits. With further refinement, the flux-quanta technology could provide a superior pathway to practical quantum computation.

Many current efforts to carry out quantum logic operations—the basic units of computation—use short microwave pulses to control the qubits. Currently, however, this technology is difficult to scale up beyond 1,000 qubits. But the presence of environmental noise requires error-correction methods that rely on large numbers of qubits, perhaps a million or more, for an effective error-correcting system that performs useful computations, according to some estimates.

Measurements conducted over an unprecedented span of conditions uncover universal behavior, but not the kind that theorists expected.

Turbulence is a mesmerizing, chaotic state of fluid motion. It occurs in natural and artificial settings whenever the Reynolds number (quantifying the relative size of inertial to viscous forces in the flow) is large. Through nonlinear coupling, kinetic energy cascades from large scales to ever smaller scales (Fig. 1) until it is dissipated by viscous effects. The fluctuations excited during this process play a crucial role in a diverse range of problems, including planetesimal formation [1], rain initiation in clouds [2], and heat transport within oceans [3]. Remarkably, a new experimental study by Christian Küchler of the Max Planck Institute for Dynamics and Self-Organization in Germany and co-workers provides compelling evidence that current theoretical models for how the fluctuations are distributed across the scales are missing some important ingredients [4].

Turbulent flows are complex. Quantitative predictions of their properties that are derived directly from the Navier-Stokes equation, without ad hoc assumptions, are accordingly scarce. Most theoretical approaches have perforce been phenomenological, the most famous being Andrey Kolmogorov’s groundbreaking 1941 theory, nicknamed K41 [5]. This mean-field theory assumes that the multiscale properties of the turbulent fluctuations are governed by the average cascade of kinetic energy passing through the scales and by the fluid viscosity. In K41 Kolmogorov went on to propose the existence of an inertial range, which corresponds to an intermediate range of scales over which viscous forces could be ignored relative to inertial forces and where the details of the large-scale forcing are unimportant.

As fish wriggle, they create a complex push–pull pattern in the water that propels them forward. Many studies have shown how the motion of a fish’s tail forms a vortex around its leading edge that provides thrust; however, it has been difficult to capture how the water flow around other parts of the fish interacts with this vortex to impact the overall propulsion. Jiacheng Guo at the University of Virginia and colleagues recently demonstrated how different fins create currents that can constructively interact to improve swimming efficiency [1].

Guo and colleagues studied how the flow around the lower back—or anal—fin interacts with the flow around the tail—or caudal—fin. First, they took a high-resolution video of a swimming rainbow trout and created a computational fluid dynamics model to accurately reproduce the fish’s motion and the water currents that it induced. Then they modified the anal fin in the model to see how this would change the pattern of water flow around the trout and affect the forward thrust.

The researchers found that the anal fin increases propulsion in two ways. It creates a vortex that stabilizes and strengthens the caudal-fin vortex, and it helps maintain a pressure difference across the fish’s body that reduces drag. Changes to the size or position of the anal fin decreased the swimming efficiency, demonstrating that the natural fish physiology is optimal.