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Oxidation numbers have so far eluded any rigorous quantum mechanical definition. A new SISSA study, published in Nature Physics, provides such a definition based on the theory of topological quantum numbers, which was honored with the 2016 Nobel Prize in Physics, awarded to Thouless, Haldane and Kosterlitz. This result, combined with recent advances in the theory of transport achieved at SISSA, paves the way to an accurate, yet tractable, numerical simulation of a broad class of materials that are important in energy-related technologies and planetary sciences.

Every undergraduate student in the natural sciences learns how to associate an integer oxidation number to a chemical species participating in a reaction. Unfortunately, the very concept of oxidation state has thus far eluded a rigorous quantum mechanical definition, so that no method was known until now to compute oxidation numbers from the fundamental laws of nature, let alone demonstrate that their use in the simulation of charge transport does not spoil the quality of numerical simulations. At the same time, the evaluation of electric currents in ionic conductors, which is required to model their transport properties, is presently based on a cumbersome quantum-mechanical approach that severely limits the feasibility of large-scale computer simulations. Scientists have lately noticed that a simplified model where each atom carries a charge equal to its oxidation number may give results in surprising good agreement with rigorous but much more expensive approaches.

Researchers at the University of Southampton and the Korea Institute for Advanced Study have recently showed that supersymmetry is anomalous in N=1 superconformal quantum field theories (SCFTs) with an anomalous R symmetry. The anomaly described in their paper, published in Physical Review Letters, was previously observed in holographic SCFTs at strong coupling, yet their work confirms that it is already present in the simplest free STFCs.

“Supersymmetry is a symmetry that relates particles with integer and half-integer spin, and has played a central role in many advances in theoretical physics since its discovery,” Kostas Skenderis, one of the researchers who carried out the study, told Phys.org. “It has been used as a means to understand the behavior of strongly interacting quantum systems where our usual theoretical tools (perturbation theory) are not applicable, as well as in some of the main candidates for beyond the Standard Model physics.”

Supersymmetry underlies the mathematical consistency of string theory, which is the most complete theory of quantum gravity proposed so far. A quantum anomaly, such as that observed by the researchers, is essentially the failure of a symmetry to be preserved at a quantum level. These anomalies typically come in two types: “bad” ones, which render string theory mathematically inconsistent and “healthy” ones, which capture important quantum properties of the theory.

Condensation might ruin a wood coffee table or fog up glasses when entering a warm building on a winter day, but it’s not all inconveniences; the condensation and evaporation cycle has important applications.

Water can be harvested from “thin air,” or separated from salt in desalination plants by way of condensation. Due to the fact condensing droplets take heat with them when they evaporate, it’s also part of the cooling process in the industrial and high-powered computing arenas. Yet when researchers took a look at the newest method of condensation, they saw something strange: When a special type of surface is covered in a thin layer of oil, condensed water droplets seemed to be randomly flying across the surface at high velocities, merging with larger droplets, in patterns not caused by gravity.

“They’re so far apart, in terms of their own, relative dimensions”—the droplets have a diameter smaller than 50 micrometers—” and yet they’re getting pulled, and moving at really high velocities,” said Patricia Weisensee, assistant professor of mechanical engineering & materials science in the McKelvey School of Engineering at Washington University in St. Louis.

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There’s only a few days left before our second conference in New York City takes place, and June has brought a lot of exciting news, such as the results of UNITY’s senolytic human trial, as well as a number of episodes of LifeXtenShow, our new YouTube show that is now a little over a month old already. Let’s dig into the details!

LEAF News

The Hubble Space Telescope recently spotted a gorgeous “in bloom” spiral galaxy and it shows vibrant star formation pockets that look like red flowers.

The spiral galaxy, which is named NGC 972, was shared by the Hubble Space Telescope on Monday, July 1. NGC 972’s orange-pink glow comes from hydrogen gas reacting to intense light beaming outwards from neighboring newborn stars, said a Hubble Space Telescope press release. These bright patches, which are scattered near various cosmic dust streams, are “blooming” like roses in NGC 972.

DARPA-funded chemists at the Massachusetts Institute of Technology (MIT) have devised a way to rapidly synthesize and screen millions of novel proteins that could be used as drugs against Ebola and other viruses. The team supports DARPA’s Fold F(x) synthetic chemistry program.

MIT News Office • Building 11–400 Massachusetts Institute of Technology • Cambridge, MA 02139–4307.

Certain plants, insects, crustaceans and fish possess the uncanny ability to change the sex of their offspring before they are born. Mammals have never before demonstrated this genetic skill, until now.

A new Tel Aviv University study reveals a genetic system in mammals that enables two animals to mate and produce only females. A similar system based on identical principles would produce only males.

Research for the breakthrough study was led by Prof. Udi Qimron, Dr. Ido Yosef and Dr. Motti Gerlic and conducted by Dr. Liat Edry-Botzer, Rea Globus, Inbar Shlomovitz and Prof. Ariel Munitz, all of the Department of Clinical Microbiology and Immunology at TAU’s Sackler School of Medicine. The research was published on July 1 in EMBO Reports.

At three o’clock in the afternoon on September 4, 1882, the electrical age began. The Edison Illuminating Company switched on its Pearl Street power plant, and a network of copper wires came alive, delivering current to a few dozen buildings in the surrounding neighborhood.

Electroactive bacteria were running current through “wires” long before humans learned the trick.