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    Fourth State Of Matter Gets Beautiful
    By News Staff | November 8th 2010 12:10 AM | 1 comment | Print | E-mail | Track Comments
    Can plasma be beautiful?   Surely, anything can, but physicists are luckier than most because when they probe the mysteries of plasma, the fourth state of matter, they often discover phenomena of striking beauty. 

    Plasmas support a large variety of waves, some familiar to all such as light and sound waves, but a great many exist nowhere else and one of the fundamental waves in magnetized plasma is the shear Alfvén wave, named after Nobel Prize winning scientist Hannes Alfvén, who predicted their existence.

    Shear waves of various forms have been a topic of experimental research for more than 15 years in the Large Plasma Device (LAPD) at the University of California, Los Angeles. When the waves were first studied, it was discovered that their creation gives rise to exotic spatial patterns, such as the one below, all of them Shear Alfvén waves.


    Three-dimensional data, such as the magnetic field of the wave shown here, will be presented along with relevant theory in a presentation at the 52nd annual meeting of the APS Division of Plasma Physics. Part of the presentation will be in 3D.

    three-dimensional magnetic field due to four currents threading the center of each helix of a shear Alfvén wave
    Representation of the three-dimensional magnetic field (due to four currents threading the center of each helix) of a shear Alfvén wave, acquired at an instant of time throughout the volume of a large (60 cm diameter ,18m long) plasma in the LAPD device at UCLA. The currents and the field topology change in fractions of a millionth of a second. The sparkles are proportional to the electric field in the plasma induced by the wave.  Credit: Walter Gekelman, UCLA

    It has become accepted that Alfvén waves are important in a wide variety of physical environments. They play a central role in the stability of the magnetic confinement devices used in fusion research, give rise to aurora formation in planets, and are thought to contribute to heating and ion acceleration in the solar corona.  Shear waves can also cause particle acceleration over considerable distances in interstellar space.

    Comments

    Bonny Bonobo alias Brat
    In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. The basic premise is that heating a gas dissociates its molecular bonds, rendering it into its constituent atoms. Further heating leads to ionization (a loss of electrons), turning it into a plasma: containing charged particles, positive ions and negative electrons. See http://en.wikipedia.org/wiki/Plasma_%28physics%29
    Yes plasma can be very beautiful. Terrestrial Plasmas include lightning, ball lightning, St. Elmo's fire, sprites, elves, jets, the ionosphere and the polar aurorae and I am fascinated by them all, but I find ball lightning especially interesting see http://en.wikipedia.org/wiki/Ball_lightning partly because there is a black hole hypothesis behind their creation :-
    Another hypothesis is that some ball lightning is the passage of microscopic primordial black holes through the Earth's atmosphere as proposed by Mario Rabinowitz in Astrophysics and Space Science journal in 1999. Inspired by M. Fitzgerald’s account of ball lightning on 6 August 1868, in Ireland that lasted 20 minutes and left a 6 meter square hole, a 90 meter long trench, a second trench 25 meters long, and a small cave in the peat bog, Pace VanDevender, a plasma physicist at Sandia National Laboratories in Albuquerque, New Mexico, and his team found depressions consistent with Fitzgerald’s report and inferred that the evidence is inconsistent with thermal (chemical or nuclear) and electrostatic effects.

    An electromagnetically levitated, compact mass of over 20,000 kg would produce the reported effects but requires a density of more than 2000 times the density of gold, which implies a miniature black hole. He and his team found a second event in the peat-bog witness plate from 1982 and are currently trying to geolocate electromagnetic emission consistent with the hypothesis. His colleagues at the institute agreed that, implausible though the hypothesis seemed, it was worthy of their attention.
    Tesla claimed to have created ball lightning in his experiments, here are a few amusing Youtube clips of people playing around with Tesla Coils to create plasma see :- http://www.youtube.com/watch?v=SlNGKly09CQ&feature=related and Musical Tesla Coils Dance of the Sugar Plum Fairy see http://www.youtube.com/watch?v=Opf5jIukSBM&feature=related
    My latest forum article 'Australian Researchers Discover Potential Blue Green Algae Cause & Treatment of Motor Neuron Disease (MND)&(ALS)' Parkinsons's and Alzheimer's can be found at http://www.science20.com/forums/medicine