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Feb 28, 2024

Nonreciprocal Frustration Meets Geometrical Frustration

Posted by in categories: education, energy, mathematics, physics

New theoretical work establishes an analogy between systems that are dynamically frustrated, such as glasses, and thermodynamic systems whose members have conflicting goals, such as predator–prey ecosystems.

A system is geometrically frustrated when its members cannot find a configuration that simultaneously minimizes all their interaction energies, as is the case for a two-dimensional antiferromagnet on a triangular lattice. A nonreciprocal system is one whose members have conflicting, asymmetric goals, as exemplified by an ecosystem of predators and prey. New work by Ryo Hanai of Kyoto University, Japan, has identified a powerful mathematical analogy between those two types of dynamical systems [1]. Nonreciprocity alters collective behavior, yet its technological potential is largely untapped. The new link to geometrical frustration will open new prospects for applications.

To appreciate Hanai’s feat, consider how different geometric frustration and nonreciprocity appear at first. Frustration defies the approach that physics students are taught in their introductory classes, based on looking at the world through Hamiltonian dynamics. In this approach, energy is to be minimized and states of matter characterized by their degree of order. Some of the most notable accomplishments in statistical physics have entailed describing changes between states—that is, phase transitions. Glasses challenge that framework. These are systems whose interactions are so spatially frustrated that they cannot find an equilibrium spatial order. But they can find an order that’s “frozen” in time. Even at a nonzero temperature, everything is stuck—and not just in one state. Many different configurations coexist whose energies are nearly the same.

Feb 28, 2024

A General Equation of State for a Quantum Simulator

Posted by in categories: information science, particle physics, quantum physics

Researchers have characterized the thermodynamic properties of a model that uses cold atoms to simulate condensed-matter phenomena.

Feb 28, 2024

Light stimulates a new twist for synthetic chemistry

Posted by in categories: biotech/medical, chemistry, computing

Molecules that are induced by light to rotate bulky groups around central bonds could be developed into photo-activated bioactive systems, molecular switches, and more.

Researchers at Hokkaido University, led by Assistant Professor Akira Katsuyama and Professor Satoshi Ichikawa at the Faculty of Pharmaceutical Sciences, have extended the toolkit of synthetic chemistry by making a new category of molecules that can be induced to undergo an internal rotation on interaction with . Similar processes are believed to be important in some natural biological systems.

Synthetic versions might be exploited to perform photochemical switching functions in molecular computing and sensing technologies or in bioactive molecules, including drugs. Their report is pending in Nature Chemistry.

Feb 28, 2024

Pythagoras was wrong: There are no universal musical harmonies, study finds

Posted by in category: media & arts

The tone and tuning of musical instruments has the power to manipulate our appreciation of harmony, new research shows. The findings challenge centuries of Western music theory and encourage greater experimentation with instruments from different cultures.

According to the Ancient Greek philosopher Pythagoras, ‘consonance’—a pleasant-sounding combination of notes—is produced by special relationships between simple numbers such as 3 and 4. More recently, scholars have tried to find psychological explanations, but these ‘integer ratios’ are still credited with making a chord sound beautiful, and deviation from them is thought to make music ‘dissonant,’ unpleasant sounding.

But researchers from the University of Cambridge, Princeton and the Max Planck Institute for Empirical Aesthetics, have now discovered two key ways in which Pythagoras was wrong.

Feb 28, 2024

Linking environmental influences, genetic research to address concerns of genetic determinism of human behavior

Posted by in categories: biotech/medical, genetics, neuroscience

It has long been known that there is a complex interplay between genetic factors and environmental influences in shaping behavior. Recently it has been found that genes governing behavior in the brain operate within flexible and contextually responsive regulatory networks. However, conventional genome-wide association studies (GWAS) often overlook this complexity, particularly in humans where controlling environmental variables poses challenges.

In a new perspective article published on February 27 in the open-access journal PLOS Biology by researchers from the University of Illinois Urbana-Champaign and Rutgers University, U.S., the importance of integrating environmental effects into genetic research is underscored. The authors discuss how failure to do so can perpetuate deterministic thinking in genetics, as historically observed in the justification of eugenics movements and, more recently, in cases of racially motivated violence.

The authors propose expanding GWAS by incorporating environmental data, as demonstrated in studies on aggression in , in order to get a broader understanding of the intricate nature of gene-environment interactions. Additionally, they advocate for better integration of insights from animal studies into human research. Animal experiments reveal how both genotype and environment shape brain gene regulatory networks and subsequent behavior, and these findings could better inform similar experiments with people.

Feb 28, 2024

Enter the gridworld: Using geometry to detect danger in AI environments

Posted by in category: robotics/AI

Spacetime is a conceptual model that fuses the three dimensions of space (length, width, and breadth) with the fourth dimension of time. By doing so, a four-dimensional geometric object is created. Researchers have recently used a similar way of thinking to study AI environments, leading to a unique reframing of AI problems in geometric terms.

Dr. Thomas Burns, a Ph.D. graduate and Visiting Researcher at the Okinawa Institute of Science and Technology (OIST), and Dr. Robert Tang, a mathematician at Xi’an Jiaotong-Liverpool University and a former post-doctoral researcher at OIST, wanted to study AI systems from a geometric perspective to more accurately represent their properties.

Continue reading “Enter the gridworld: Using geometry to detect danger in AI environments” »

Feb 28, 2024

Scientists Develop Method To Cool One of the World’s Hottest Cities by 8°F

Posted by in categories: climatology, materials

A recent study from UNSW Sydney demonstrates that significant reductions in the temperatures of major cities located in hot desert climates can be achieved alongside decreases in energy expenses.

The findings, recently published in Nature Cities, detail a multi-faceted strategy to cool Saudi Arabia’s capital city by up to 4.5°C, combining highly reflective ‘super cool’ building materials developed by the High-Performance Architecture Lab with irrigated greenery and energy retrofitting measures. The study, which was conducted in collaboration with the Royal Commission of Riyadh, is the first to investigate the large-scale energy benefits of modern heat mitigation technologies when implemented in a city.

“The project demonstrates the tremendous impact advanced heat mitigation technologies and techniques can have to reduce urban overheating, decrease cooling needs, and improve lives,” says UNSW Scientia Professor Mattheos (Mat) Santamouris, Anita Lawrence Chair in High-Performance Architecture and senior author of the study.

Feb 28, 2024

Beyond Moore’s Law: New Strategy for Developing Highly Versatile Electronics With Outstanding Performance Discovered

Posted by in categories: computing, economics, nanotechnology

The miniaturization of electronic components, including transistors, has hit a plateau, presenting obstacles in the production of semiconductors. Nonetheless, a group of researchers, led by experts in materials science from the City University of Hong Kong (CityUHK), has unveiled a novel approach for creating highly versatile and high-performing electronics using transistors made of mixed-dimensional nanowires and nanoflakes. This breakthrough facilitates easier chip circuitry design and promotes the development of future electronic devices that are both flexible and energy-efficient.

In recent decades, as the continuous scaling of transistors and integrated circuits has started to reach physical and economic limits, fabricating semiconductor devices in a controllable and cost-effective manner has become challenging. Further scaling of transistor size increases current leakage and thus power dissipation. Complex wiring networks also have an adverse impact on power consumption.

Multivalued logic (MVL) has emerged as a promising technology for overcoming increasing power consumption. It transcends the limitations of conventional binary logic systems by greatly reducing the number of transistor components and their interconnections, enabling higher information density and lower power dissipation. Significant efforts have been devoted to constructing various multivalued logic devices, including anti-ambipolar transistors (AAT).

Feb 28, 2024

The Altermagnetism Breakthrough: A New Dimension of Magnetism Explored

Posted by in categories: innovation, materials

Researchers at Mainz University have been able to visualize the third class of magnetism, called altermagnetism, in action.

Ferromagnetism and antiferromagnetism have long been known to scientists as two classes of magnetic order of materials. Back in 2019, researchers at Johannes Gutenberg University Mainz (JGU) postulated a third class of magnetism, called altermagnetism. This altermagnetism has been the subject of heated debate among experts ever since, with some expressing doubts about its existence.

Recently, a team of experimental researchers led by Professor Hans-Joachim Elmers at JGU was able to measure for the first time at DESY (Deutsches Elektronen-Synchrotron) an effect that is considered to be a signature of altermagnetism, thus providing evidence for the existence of this third type of magnetism. The research results were published in Science Advances.

Feb 28, 2024

Beyond Binary: The Light-Driven Computing Revolution

Posted by in categories: computing, mapping

Researchers develop a computer from an array of VCSELs with optical feedback.

In our data-driven era, solving complex problems efficiently is crucial. However, traditional computers often struggle with this task when dealing with a large number of interacting variables, leading to inefficiencies such as the von Neumann bottleneck. A new type of collective state computing has emerged to address this issue by mapping these optimization problems onto something called the Ising problem in magnetism.

Understanding the Ising Problem.