The band theory of metals has been experimentally tested many times and is now the accepted model of the behaviour of conductors and insulators. Electrical resistance is due to collisions of the electrons (whether treated as particles or waves) with impurities, imperfections, and especially the lattice vibrations of the metal crystal. The lattice vibrations of […]
Discarded electronic devices, such as cell phones, are a fast-growing source of waste. One way to mitigate the problem could be to use components that are made with renewable resources and that are easy to dispose of responsibly. Now, researchers have created disposable papertronics, a prototype circuit board that is made of a sheet of […]
In 1906, Alois Alzheimer, a psychiatrist and neuroanatomist, reported “a peculiar severe disease process of the cerebral cortex” to a gathering of psychiatrists in Tübingen, Germany. The case was a 50-year-old woman who suffered from memory loss, delusions, hallucinations, aggression and confusion – all of which worsened until her untimely death five years later. In […]
Black hole collision behaves as Einstein predicted Scientists studying the collision of two huge black holes observed massive gravitational waves and a phenomenon known as precession, which resembles the wobbling motion of a spinning top. Albert Einstein’s theory of general relativity predicted a century ago that precession would occur in massive objects — but this […]
There are instances in which you would intentionally deliver nanoparticles to animals (humans included). Contrast agents for medical diagnosis or therapeutic ones for medical treatments are two examples. It is also the case with plants, as some fertilizers take the form of nanoparticles. Unintentional exposure of animals or plants to nanoparticles is also possible: environmental […]
A few years ago, the chess website Chess.com temporarily banned US grandmaster Hans Niemann for playing chess moves online that the site suspected had been suggested to him by a computer program. It had reportedly previously banned his mentor Maxim Dlugy. And at the Sinquefield Cup earlier this month, world champion Magnus Carlsen resigned without […]
Occasionally I receive groups of messages from families with autistic members and I know the reason: they have read in the press exciting news about autism, a spectacular treatment, even a miracle cure. Unfortunately, if all that news were true we would have solved autism hundreds of times by now. So let’s start with the […]
Long-lost moon may have been cause of Uranus’ stark tilt Astronomers have long suspected that a series of giant impacts early in the planet’s formation flipped Uranus on its side, but new research suggests the planet’s 98-degree-tilt could have been caused by a long-lost moon. It is possible that the tilt was caused by the […]
Some materials have special universal properties protected against perturbations. Such properties are theoretically described by topology, a branch of mathematics concerned with the properties of geometrical objects that are unchanged by continuous deformations. So-called topological insulators are electronic materials that have a bulk band gap like an ordinary insulator but have conducting states on their […]
Mostly, people think that an embryo can only (except in the case of parthenogenesis) result from the sum of sperm and an egg. However, two research teams, one in Israel and another multinational collaboration have recently reported producing a synthetic mouse embryo from stem cells which lasted enough to have a brain and a beating […]