One of the greatest inventions of the 20th century, if not the greatest, was the transistor. It revolutionized the electronics industry and changed the way people around the world lived, learned, worked, and played. Its invention marked the beginning of solid state electronics which quickly reduced the size and power requirements of existing electronic tube […]
In lay people’s minds, railway lines are composed by rails and wooden sleepers on a bed of stones. These medium-sized stones are called ballast, and it is true that they are the most common material to lay the track on; at least when you are not building it in a tunnel or a bridge, where […]
Color patterns are important features of lots of animals, having key functions in protection against UV irradiation, camouflage, shoaling or sexual selection. Color patterns in birds and mammals are generated by a particular type of cell called melanocyte which produces melanin and transfers it to the tissues of fur or plumage. In fish, amphibia and […]
There are people that have the feeling that if they get to know what something is made of automatically thay have learned something. This attitude is called reductionism. But take water, for example: how knowing that water is composed of molecules and that each of these molecules is composed of two atoms of hydrogen and […]
Sunlight is the most important energy source of Earth. All earthlings live thanks to the ability of plants and bacteria to transform solar energy into chemical one. As sunlight is a free, and practically unlimited, energy source it is easy to understand the general interest in finding efficient ways of transforming it into electrical power […]
Although pretty much unknown for the public audience, Supergravity theories play an important role in modern Theoretical Physics, specially for the particle physics and (Super)String Theory communities . Loosely speaking, Supergravity is a theory that describes gravity along with other fundamental particles and interactions in such a way that the whole structure is symmetric under […]
Almost everyone with basic knowledge of physics have one clear concept, there is a minimum temperature and it is called ‘absolute zero’. This temperature corresponds to -273.15 degrees in the Celsius scale. In the Kelvin or absolute scale it is zero, by definition. Furthermore, there is another idea that is also widespread: absolute zero is […]
Everyone has heard the sound of the crack of a whip, at least in movies or TV serials like “El Zorro: The man with the whip” (1954). A shock wave is created by the supersonic motion of the tip of the whip in the air . Whipping is a typical fluid instability of an accelerating […]
Science news with bad titles usually attract a lot of attention. A recent example is “The sound of an atom has been captured” ]. Laypeople must know that atoms do not emit sound. Quantum acoustics study the propagation and the interaction of phonons, the analogues in sound to photons in light. An atom cannot emit […]
A couple of weeks ago I had the chance of having a fulfilling chat with Riccardo Cerulli, one of DAMA main researchers. They are at the very center of a skepticism tornado about their results on Dark Matter direct detection, and I asked as many questions as he let me to try to solve this […]