* PHYSICS SEMINAR *

Propulsion mechanism at low Reynolds number: Swimming of bacteria and its applications in nanotechno

연사: 김용운[고등과학원]

일시: 2007 년 4 월 18 일 15:00 ~

장소: 공학3동 201호 물리학과 세미나실

ABSTRACT:

Swimming on the micrometer scale calls for design strategies very different from the ordinary human-scale world, since inertia plays no role and friction is the only way of producing thrust. Cilia and flagella are hair-like appendages used for swimming and to stir surrounding fluids in many cells, and thus constitute essential building blocks for locomotion of microorganisms. Their design principles are the evolutionary answer to the need for generating thrust. Furthermore, recent technical developments in the synthetic manufacture of single-molecular motors raise the question about the minimal design for the effective propulsion of nano-sized machines working in a viscous media. Motivated by these, we study the hydrodynamic propulsion of a system consisting of periodically beating elastic filaments anchored to a solid surface, which resembles the ciliary surface. We find that finite stiffness of the filaments breaks the time-reversal symmetry, showing cilialike beating patterns, and enables propulsion. It also turns out that self-organized synchronization between neighboring filaments occurs autonomously via hydrodynamic coupling, shedding light on metachronal coordination on bacterial surfaces.

문의처: 성우경(054-279-2061, wsung@postech.ac.kr)