BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Exponential growth in two-dimensional topological fluid dynamics -
  Boyland\, P (University of Florida)
DTSTART:20120723T150000Z
DTEND:20120723T154000Z
UID:TALK39015@talks.cam.ac.uk
CONTACT:Mustapha Amrani
DESCRIPTION:In two-dimensional multi-connected fluid regions the Thurston-
 Nielsen (TN) theory implies that the essential topological length of mater
 ial lines grows either exponentially or linearly\; the TN theory and subse
 quent results provide many procedures for determining which growth rate oc
 curs. Our first application is to Euler flows. The main theorem is that th
 ere are periodic stirring protocols for which generic initial vorticity yi
 elds a solution to Euler's equations which is not periodic and further\, t
 he sup norm of the gradient of the vorticity grows exponentially in time. 
 The second application investigates which stirring protocols maximize the 
 efficiency of mixing in the precise\, topological sense of the maximal exp
 onential growth of per unit generator of certain push-point mapping classe
 s on the punctured disk. \n\nRelated Links\nhttp://www.math.ufl.edu/~boyla
 nd/papers.html - my paper's page \n\n
LOCATION:Seminar Room 1\, Newton Institute
END:VEVENT
END:VCALENDAR