BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Instabilities and ill-posedness for the magnetogeostrophic equatio
 n - Friedlander\, S (University of Southern California)
DTSTART:20120724T130000Z
DTEND:20120724T134000Z
UID:TALK39029@talks.cam.ac.uk
CONTACT:Mustapha Amrani
DESCRIPTION:We discuss an active scalar equation that is motivated by a mo
 del presented by Keith Moffatt for the geodynamo and magnetogeostrophic tu
 rbulence in the Earth's fluid core. We prove that the non-difusive equatio
 n is Lipshitz ill-posed in Sobolev spaces. In contrast\, the diffusive equ
 ation is globally well-posed. In this case we give an example of a steady 
 state that is nonlinearly unstable\, and hence produces a dynamo effect in
  the sense of an exponentially growing magnetic field.\n \nThis is joint w
 ork with Vlad Vicol.\n
LOCATION:Seminar Room 1\, Newton Institute
END:VEVENT
END:VCALENDAR