Ultrasound is commonly used to look at the heart, but it is unsuitable for the 10-20% of the population that have breathing difficulties (emphysema) or who are medically obese. In both techniques, patients are given drugs to speed up their hearts and promote vigorous pumping. In a healthy heart both sides of the heart contract […]
Read article: Magnetic resonance sees the heart beat
The treaty will only come into effect if the 44 countries that have the capability to develop nuclear weapons ratify it. Although 26 countries, including France and the UK, have ratified the treaty, Russia, China and the US have not. “This decision is a serious blow to the entire system of agreements in the field […]
The Vienna team sent a collimated beam of carbon-60 molecules through a slit made of silicon nitride and detected the interference pattern by ionizing the molecules with a laser and then counting the ions. The slits in the diffraction grating were 50 nanometres wide and the grating had a period of 100 nanometres. The team […]
‘t Hooft and Veltman were both born in the Netherlands. In 1966 Veltman was appointed as professor of physics at the University of Utrecht, and ‘t Hooft became his PhD student in 1969. By 1971 ‘t Hooft had made several important breakthroughs in the theoretical effort to renormalize the electroweak interaction. Then using a computer […]
Prior to Zewail’s work chemists had thought that chemical reactions occurred on the same time scale as molecular vibrations — that is, on the femtosecond scale. In the late 1980s, Zewail developed a technique that could follow the motion of atoms and molecules on these time scales. A strong laser pulse was used to start […]
Global warming – sometimes called the greenhouse effect – is caused by gases in the atmosphere that absorb and then re-emit infrared radiation, thereby ‘trapping’ the heat on the Earth instead of allowing it to escape into space. The three most common greenhouse gases are carbon dioxide, water vapour, and ozone. However, some greenhouse gases […]
The material – 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA) – is non-magnetic at very low temperatures. The paramagnetic effect is strong at room temperature, but as the compound is cooled, it becomes diamagnetic below 230 K. However, it is heated again, it does not become paramagnetic until the temperature reaches is 305K. This is an unusually wide hysteresis loop […]
Every year the Foundation asks 3000 physicists to nominate individuals for the prize, and compiles a short-list of 250 candidates. These names are then whittled down to a list of 30, from which the winners are chosen. Last year’s prize was awarded for the experimental discovery of the fractional quantum Hall effect, and its theoretical […]
The standard story about the development of physics as a separate discipline runs more or less as follows. After the Newtonian revolution of the 17th century, natural science divided into two parts: mechanics on the one hand and experimental science on the other. The latter investigated nature in a mostly qualitative way, whereas mechanics – […]
