Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Alfven waves

  1. Jan 11, 2012 #1

    What do Alfven waves look like?
    Say you have a spherical galaxy. What would the Alfven waves of the three lowest frequencies look like? I read that they are transverse waves but I can't visualize a spherical transverse wave.

    Thanks! :)
  2. jcsd
  3. Jan 12, 2012 #2


    User Avatar
    Gold Member

    I doubt that anyone could see an Alfven wave. If that is so, how could anyone answer "What do Alfven waves look like?"

    From Wikipedia: "An Alfvén wave in a plasma is a low-frequency travelling oscillation of the ions and the magnetic field. The ion mass density provides the inertia and the magnetic field line tension provides the restoring force."

    What "three lowest frequencies" are you referring to? Can you please post your source or reference for this?

    Regarding you question about "a spherical transverse wave", please see this, also from Wiki:

    "The wave propagates in the direction of the magnetic field, although waves exist at oblique incidence and smoothly change into the magnetosonic wave when the propagation is perpendicular to the magnetic field. The motion of the ions and the perturbation of the magnetic field are in the same direction and transverse to the direction of propagation. The wave is dispersionless."

    Last edited: Jan 12, 2012
  4. Jan 14, 2012 #3
    Thanks Bobbywhy!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook