CANCELLED: The Physics of Molecular Motors

Note: Cancelled due to illness
Speaker: Fabio Marchesoni, Dipartimento di Fisica, Universita' di Camerino, Italy

When: December 16, 2009 (Wed), 01:00PM to 02:00PM (add to my calendar)

This event is part of the Condensed Matter Theory Seminar Series.

Abstract: Our physical intuition, based on everyday observation of large machines, fails when we consider the world of the small. It is a capricious world, ruled by thermal and quantum fluctuations. This applies in particular to the molecular machinery of the cell: How effectively it works against the II Law of Thermodynamics has kept puzzling statistical physicists for decades.

We discuss how thermal Brownian motion coupled to an unbiased non-equilibrium environment can be used to control the operation of biological and artificial systems characterized by spatial or dynamical symmetry breaking at the micro- or even on the nano-scale. This mechanism is known in the physics literature as Brownian motor or noise rectification. The constructive role of Brownian motion is exemplified for the case of noise-induced transport in one-dimensional channels. We present the working principles and characteristics of the most common stylized Brownian motors. Such devices can be experimentally implemented to optimize and selectively control a rich variety of directed transport behaviors.