"Kelvin's Vortex Atoms -- Not Such a Bad Idea After All?"
Keith Moffatt FRS (DAMTP, Cambridge)
In 1867, William Thomson (Lord Kelvin) made his revolutionary 'vortex-atom' conjecture, to the effect that the spectra of all the then-known elements could be understood in terms of the vibrations of suitably knotted microscopic vortex structuresin a hypothetical all-pervasive ether. The theory was eventually abandoned because it emerged that all nontrivial vortex structures were unstable, in contrast to their supposed atomic counterparts. We now know however that, in a perfectly conducting fluid, there exist stable (minimum energy) magnetostatic states whose flux tubes are knotted in an arbitrarily prescribed manner. Such states have recently been proposed in quantum chromodynamics, to represent the structure of glueballs in the 'quark-gluon' plasma of the early Universe. Kelvin's ideas, suitably modified, thus come to life once again at this most fundamental level of current elementary particle physics; and merit in this his centenary year the review that this lecture will aim to provide.
The first picture of the magnetosphere was taken by special ultraviolet camera carried to the moon by the Apollo 16 mission (at right). This showed only discrete portion, the geocorona, a ring of electrified helium circling the Earth and glowing in ultraviolet light.
More recently, the Dynamics Explorer 1 (launched in 1981) and Polar spacecraft (1995) have carried cameras that take visible, ultraviolet, and even X-ray images of the auroral regions from space.
Right: The first image taken of the geocorona, a halo of low density hydrogen around the Earth (center) photographed by Astronaut John W. Young, Apollo 16 commander, in April of 1972, with an ultraviolet camera. The geocorona is bright on the sunlit side. Exposure 15 seconds, with F/1 electronographic camera. The streaks and circular patch on right are instrumental. Click for a larger picture.
Earth’s magnetic field perturbed by 'electric oceans', claims researcher
Abstract: The time evolution of a system where a uniform and classical SU(3) color electric field and quantum fields of quarks are dynamically coupled with each other is studied focusing on non-perturbative pair creation and its back reaction. We characterise the color direction of the electric field in a gauge invariant way, and investigate its dependence. Momentum distributions of created quarks show plasma oscillation as well as quantum effects such as the Pauli blocking and interference. Pressure of the system is also calculated, and we show that pair creation moderates degree of anisotropy of pressure. Furthermore, enhancement of pair creation and induction of chiral charge under a color magnetic field which is parallel to the electric field are discussed.
ScienceDaily (Feb. 18, 2010) — Jets of particles streaming from black holes in far-away galaxies operate differently than previously thought, according to a study published February 17 in Nature. The new study reveals that most of the jet's light -- gamma rays, the universe's most energetic form of light -- is created much farther from the black hole than expected and suggests a more complex shape for the jet.
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