Lifeboat Foundation

Ticking clocks and flashing fireflies that start out of sync will fall into sync, a tendency that has been observed for centuries. A discovery two decades ago therefore came as a surprise: the dynamics of identical coupled oscillators can also be asynchronous. The ability to fall in and out of sync, a behavior dubbed a chimera state, is generic to identical coupled oscillators and requires only that the coupling is nonlocal. Now Yasuhiro Yamada and Kensuke Inaba of NTT Basic Research Laboratories in Japan show that this behavior can be analyzed using a lattice model (the XY model) developed to understand antiferromagnetism [1]. Besides a pleasing correspondence, Yamada and Inaba say that their finding offers a path to study the partial synchronization of neurons that underlie brain function and dysfunction.

The chimera states of a system are typically analyzed by looking at how the relative phases of the coupled oscillators fall in and out of sync. But that approach struggles to describe the system when the system contains distantly separated pockets of synchrony or when there are nontrivial configurations of the oscillators, such as twisted or spiral waves. It also requires knowledge of the network’s structure and the oscillators’ equations of motion.

In seeking an alternative approach, Yamada and Inaba turned to a two-dimensional lattice model used to tackle phase transitions in 2D condensed-matter systems. A crucial ingredient in that model is a topological defect called a vortex. Yamada and Inaba found that they could embody the asynchronous dynamics of pairs of oscillators by formulating the problem in terms of an analogous quantity that they call pseudovorticity, whose absence indicates synchrony and whose presence indicates asynchrony. Their calculations show that their pseudo-vorticity-containing lattice model can successfully recover the chimera state behavior of a simulated neural network made up of 200 model oscillators of a type commonly used to study brain activity.

Long-distance quantum communication can be achieved by directly sending light through space using a train of orbiting satellites that function as optical lenses.

Dissipation affects the time asymmetry of fluctuations in systems out of thermodynamic equilibrium. A newly discovered inequality elucidates that connection.

The emergent field of stochastic thermodynamics uses random variables to investigate the dynamics of microscopic systems that operate out of thermodynamic equilibrium, such as active matter and metabolic pathways. Now Naruo Ohga and two colleagues at the University of Tokyo have applied tools from stochastic thermodynamics to uncover a universal law that could find broad applications in the description of active matter, cell metabolism, and other systems whose continuous supply of energy keeps them out of equilibrium [1] (Fig. 1.)

When a thermodynamic system is close to equilibrium, the fluxes of physical quantities, such as energy and electric charge, are linearly proportional to thermodynamic forces, such as temperature gradients and voltage differences. The coefficients connecting the fluxes and forces are symmetric, meaning that the one relating flux A to force B is the same as the one relating flux B to force A. Such symmetries are known as Onsager’s reciprocal relations [2]. At the microscopic level, their origin can be attributed to the time-reversal symmetry of the cross-correlation function between two physical quantities at equilibrium.

WASHINGTON — Russia’s first lunar mission in nearly half a century suffered an “emergency situation” during an attempted maneuver Aug. 19, putting plans for a landing into question.

In a brief statement posted to its channel on the social media service Telegram, the Russian space agency Roscosmos said that the Luna-25 spacecraft was commanded to perform a maneuver at 7:10 a.m. Eastern to place the spacecraft into a “pre-landing” orbit around the moon.

However, during the planned maneuver “an emergency situation occurred on board the automatic station, which did not allow the maneuver to be performed with the specified parameters,” according to a translation of the statement. “The management team is currently analyzing the situation.”

SINGAPORE, 14 April 2023 – A preclinical study using stem cells to produce progenitor photoreceptor cells—light-detecting cells found in the eye—and then transplanting these into experimental models of damaged retinas has resulted in significant vision recovery. This finding, by scientists at Duke-NUS Medical School, the Singapore Eye Research Institute and the Karolinska Institute in Sweden, marks a first step towards potentially restoring vision in eye diseases characterised by photoreceptor loss.

Research reveals a promising stem cell approach to correct photoreceptor cell degeneration, which underlies several forms of visual decline and blindness.

People are having sex in the backseat while their driverless robotaxi is ferrying them to their final destination in San Francisco.

The universe is not only expanding but accelerating away from us. Now a new theory suggests all this could stop sooner than anyone imagined.

X-ray and optical imaging of the freezing of supercooled water droplets.

So if I understand this…send a bot to catch a bot?

Israeli tech start-up Cyabra, which worked with Elon Musk to evaluate the presence of bots on Twitter, released a new tool that can detect AI-generated text, images and profiles.