Without any conflict with the second law of thermodynamics, heat can flow from a cooler but constantly heated body to another thermally connected and constantly hotter body. This anomalous heat transfer has been demonstrated in a two-phase liquid-vapor system composed of a Rayleigh–Bénard convection (RBC) cell filled one-half with normal liquid helium and one-half with […]
Maples rely on wind, upward currents, and gusts to spread their seeds over long distances that can reach several kilometers. Maple seeds are able to autorotate because their center of gravity, determined by the position of the nut, is located at the base of the wing-shaped seed. It has been observed that, despite their small […]
Power has always been an issue of particular importance for the social sciences, in general, and for Political Economy in particular. Many studies in this field, from different approaches, have wondered about the nature, structure and sources of power. Particularly noteworthy are those authors –such us Susan Strange, Stephen Gill of Ulrich Beck– who have […]
Since the first half of the 19th century, philologists and historians have been examining the extant evidence about the origins of Christianism and Judaism, particularly studying the books of the Bible with the methods applied to any other old document. Though this research faced strong opposition both from most Christian denominations and from some of […]
Humanities & Social Sciences • Science • Technology • Weekly Selection
Pear-shaped nuclei in some atoms may help explain antimatter Researchers have used a particle accelerator called REX-ISOLDE at CERN in Switzerland to discover an atom with pear-shaped nuclei. The discovery could lead scientists to extend the Standard Model in physics and help to explain why there is more matter than antimatter in the universe. LiveScience […]
There are few cases in the history of physics in which a particle, theoretically predicted, has been detected repeatedly and not identified as such. This is what happened to the positron. Paul Dirac showed in 1928 that it could be the case that a particle could have negative energy but a positive charge. It was […]
Bees visit flowers to obtain nectar (a sugary liquid) and pollen (their source of fat and protein). During foraging trips, bees do not choose flowers at random. For example, as first pointed out by Aristotle, bees visit only one type of flower in each of their foraging trips. How do bees recognise flowers? Colour textures […]
Consider a set of distinct points in the plane, no three of them on the same line. Draw straight-line segments joining pairs of those points. This is called a geometric graph and here we are going to focus on the segments of such a graph. Every segment has two sides, defined by the line in […]
There are some science news that appear recursively in the media. Just to stick to my field of knowledge we could point to Mars’ water and habitability of extra solar planets. It is certainly great to have people reading about those topic, although some confusion seems to have settled down among public opinion. I am […]
Cryptography is, beyond any doubt, an important technology. Keeping the privacy of communications has many applications in modern societies. For instance, being able to send a message, as your credit card number, with the confidence that no one will understand it if it is intercepted, is a basic assumption for electronic transactions. Also, nowadays and […]