Two of the oldest and largest physical societies in the world celebrate anniversaries this year. The Institute of Physics, which publishes this magazine, can trace its roots back to the Physical Society that was formed in London 125 years ago. And the American Physical Society (APS) is currently celebrating its centennial. Other venerable societies of […]
Sascha Hilgenfeldt, Siegfried Grossman and Detlef Lohse extended the model by making the bubble’s temperature dependent on its volume and by making an allowance of the small emissivity of the weakly ionized gas inside the bubble. The latter term allows for the fact that experiments have shown that only Nobel gases remain inside the bubble […]
According to the Standard Model of particle physics, the three types of neutrinos – electron, muon and tau neutrinos – have zero mass. But the number of atmospheric neutrinos – muon neutrinos created by interactions between cosmic rays and nuclei in the atmosphere – detected in experiments is significantly less than that predicted by the […]
The glass tube in a conventional fluorescent light is coated on the inside with a phosphor layer and filled with a discharge material, usually mercury. Electrons excite the mercury atoms from the ground state into a short-lived excited state. Ultraviolet light is emitted as the atoms return to the ground state and this is absorbed […]
Read article: Phosphors help switch on xenon
String theory is seen as a way of reconciling Einstein’s theory of relativity with quantum mechanics. According to the theory, the fundamental particles and their interactions are generated by the vibrations of tiny loops of string. Progress in the field has been rapid in recent years. Recent breakthroughs have included the demonstration that five previously […]
Fink and Schönenberger made their measurements by placing discrete amounts of DNA molecules in a water-based solution. A tiny droplet of the solution was then placed onto a gold-coated carbon foil. Blotting paper was then used to remove most of the water on the device, causing some of the individual DNA molecules to span the […]
Recent experiments in fluid mechanics are shedding light on the intricate motion displayed by non-spherical objects as they fall, a problem that has puzzled physicists for centuries
Read article: Flutter and tumble in fluids
In 1994 the Nobel Prize for Physics was awarded to Cliff Shull and Bert Brockhouse for, in the words of the Nobel committee’s citation, showing “where atoms are” and “what atoms do”, respectively. Some 40 years ago Shull and Brockhouse developed and demonstrated a uniquely powerful and universally applicable non-destructive technique for probing the structures […]
Read article: Neutron scattering: strategic necessity or expensive luxury?
Although scientists have known about gamma-ray bursts since 1967, no one has come up with a feasible explanation of why they occur. The explosions may be caused by the collision of super-dense neutron stars; the sudden collapse of a massive star into a black hole; or other, exotic mechanisms. Many astronomers believe that the gamma […]
The radiation causes the eumelanin to generate large quantities of free oxygen radicals, which in turn damage cell DNA and hence may lead to cancer. His research was reported yesterday at the annual American Physical Society meeting in Atlanta, Georgia.
