Purpose of the Workshop
Brownian motion is a basic stochastic process, whose discovery is credited to
the botanist Robert Brown in 1827. He observed that small particles suspended in
a fluid are in continuous movement and he formulated the daring hypothesis that
this might have something to do with the origin of life. This discovery did not
receive much attention in the physics community, until before the turn of the
20th century when Guoy linked Brownian motion with the molecular hypothesis by
arguing that this erratic motion is the result of the collision of the particle
with surrounding thermally agitated molecules.
This idea received a
brilliant confirmation in 1905 when Einstein related the mathematical law
governing Brownian motion to the principles of the kinetic-molecular theory of
heat. The predictions of this theory, independently published by M. v.
Smoluchowski one year later, were confirmed by the famous experiments by
Perrin. His measurements on the Brownian motion of latex particles suspended in
a fluid allowed the first accurate estimation of the Avogadro number. After
this spectacular success, Brownian motion quickly developed into a central
conceptual tool in many scientific theories and applications.
Historians refer to the year of 1905 as Einstein’s annus
mirabilis – “the miracle year” when he completed and published his major
studies on the special theory of relativity, the quantum theory, and the theory
of Brownian motion. Due to the upcoming centenary of “the miracle year”, UNESCO
has declared 2005 the “World Year of Physics”. Consequently,
numerous activities, exhibitions, and conferences are presently being
prepared worldwide.
This Conference is intended to gather a relatively smaller number of experts from different areas of natural sciences (but also from engineering, social sciences, medicine) to discuss the state of the art and the new horizons of this topic in a more relaxed but technical format. Particular attention will be devoted to a new approach to fluctuations that has been emerging in recent years. It is common perception that noise, often related to microscopic Brownian motion, degrades the information contained in the system response, destroys temporal and spatial patterns; hence, the effort at minimizing noise. When dealing with microscopic devices our attitude towards noise changes necessarily: Noise is unavoidable but can be exploited to magnify certain properties of the nonlinear system response, thus realizing new ordered behaviours or enhancing signal transmission. Transport in ion-channels, synchronization/coherence in chemical and biological extended systems, virus propagation, forecasting protocols are just a few examples that illustrate the subtle beneficial synergy between noise and nonlinearity.
List
of Topics