ELFT HÍRADÓ

[Szeminárium koordinátor <szfi-seminar AT wigner.mta.hu>]

SZFI SeminarKirsten HarthUniversity of Magdeburg (host: Börzsönyi Tamás)From 
viscous to elastic sheets: Dynamics of thin free-standing smectic 
filmsTuesday, 3 December 2019, 10:00, KFKI Campus, Bldg. 1, 2nd floor, 
Conference RoomThin fluid membranes and bubbles are of considerable 
importance in biological, environmental, and technical contexts. Soap 
bubbles, vesicles and components of biological cells are well known examples 
where dynamic features are significantly influenced by the properties of thin 
fluid membranes enclosed by fluids. Two-dimensional membrane motions couple 
to 3D shape transformations. Smectic phases possess an internal molecular 
layer structure, which allows easy preparation of thin free-standing films. 
Those represent simple models for the study of membrane dynamics and pattern 
formation in quasi two-dimensional fluids. Literature mostly deals with 
nematic materials in sandwich cells, or planar smectic films spanned over a 
frame, with static or only slowly changing shapes and surface areas. Smectic 
films can easily be generated in the form of bubbles or catenoids as well. We 
study rapid shape transformations of smectic films and bubbles. The internal 
layer structure produces very peculiar dynamics, with a transition between a 
quasi-elastic response on short time scales and a fluid-like response to slow 
changes. The seminar will discuss exemplary experimental situations, 
including shape relaxation of bubbles in micro-gravity conditions and film 
rupture. We present first numerical results reproducing the phenomena 
qualitatively. Minden érdeklődőt szívesen látunk! - Everyone is welcome 
to attend.Róbert Juhászszfi-seminar AT wigner.mta.hu