Some asteroids are pulled into near-Earth orbits by gravitational resonance effects created by the combined pulls of Mars, Jupiter and Saturn. However, it has been known for many years that another mechanism must be pulling asteroids out of their more typical Mars- Jupiter orbit. Farinella and Vokrouhlicky suggest that when large asteroids collide, their fragments […]
The existence of superheavy elements was predicted about 30 years ago on the basis of the nuclear shell model, which was originally developed in 1949. The model explains why nuclei with certain “magic” numbers of neutrons or protons are especially stable: these nuclei have closed shells of either protons or neutrons. Magic nuclei are spherical […]
Three major reports have already been published – on atomic, molecular and optical science; plasma science; and elementary-particle physics – and reports on nuclear physics and gravitational physics are being completed. A separate NRC panel is preparing a report on astronomy and astrophysics. The latest Physics in a New Era report to emerge, Condensed-Matter and […]
To what extent should a formal education in ethics be part of the university physics curriculum? When this question is raised in the physics community, the response is often that there is no significant problem with fraud in physics, and hence that including ethics in the curriculum is unnecessary. Even raising the question is viewed […]
Read article: Molecular materials make their mark
Basic research into the optical, electronic and magnetic properties of organic and molecular materials is thriving, and has led to a new generation of electronic devices and displays
Some researchers remain adamant that cold fusion is real, as David Voss reports
Wiik was born in Norway in 1937. He moved to Germany in 1956 and after spending several years in the United States, joined the Hamburg laboratory in 1972. At DESY he was a member of the TASSO collaboration, one of four groups studying electron-positron collisions at the PETRA collider. In 1979 the TASSO collaboration won […]
The stellar history of local galaxies is calculated by plotting the different size and brightness of stars in the target galaxy. However, when viewed from Earth, star systems and star clusters can sometimes appear as a single bright star. The photographs taken with the Wide-Field Planetary Camera indicate that this mistake has happened with at […]
Physicists hope to develop new ways of accelerating particles because of the high cost and large size of traditional accelerators. Electrons in standard accelerators gain energy by surfing large electromagnetic (EM) waves contained by powerful magnetic fields. However it may be possible to adapt the intense EM waves generated when a laser pulse interacts with […]
The pairs are created by illuminating a semiconductor quantum well with a pulsed laser diode. A slight voltage difference on the semiconductor keeps the electron and the hole in separate levels inside the quantum well. When the voltage is switched off, the electron-hole pair move together under Coulomb attraction and radiatively recombine – producing a […]
