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SUMMARY:Quantum vortex dynamics by Seifert surface information - Renzo Ric
 ca (University of Milan - Bicocca)
DTSTART:20170922T103000Z
DTEND:20170922T111000Z
UID:TALK80661@talks.cam.ac.uk
CONTACT:INI IT
DESCRIPTION:Co-author: Simone Zuccher (U. Verona)<br><br>Time evolution an
 d interaction of filamentary structures is often studied by analysing  dyn
 amics in terms of local forces. An alternative route is to investigate phy
 sical or biological  properties by focussing on geometric and topological 
 properties of the surface swept out by filament motion. In this work we pr
 esent new results on the evolution\, interaction and decay of a Hopf link 
 of quantum vortices governed by the Gross-Pitaevskii equation by analysing
   physical information in terms of the iso-phase Seifert surface swept out
  during the process [1].  We interpret the surface local twist as an axial
  flow acting along the vortex filament [2] and the Seifert surface of&nbsp
 \;minimal area in terms of linear momentum of the system. We show that GP&
 nbsp\;evolution is associated with a continuous minimisation of this surfa
 ce in agreement with the physical cascade process observed.&nbsp\;This app
 roach sheds  new light on filament dynamics and bears similarities to the 
 study of fluid membranes in  biological and chemical systems.<br><br>[1] Z
 uccher\, S. & Ricca\, R.L. (2017) Relaxation of twist helicity in the casc
 ade process of linked      quantum vortices. Phys. Rev. E 95\, 053109. <br
 >[2] Zuccher\, S. & Ricca\, R.L. (2017) Twist effects in quantum vortices 
 and phase defects. Fluid      Dyn. Res.\, doi.org/10.1088/1873-7005/aa8164
 .
LOCATION:Seminar Room 1\, Newton Institute
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