l - People

Introduction
The problem of predicting the time evolution of systems with many nonlinearly coupled
degrees of freedom has long been a topic of much interest and intense work. Celestial
mechanics computations can often by performed by assuming only 1/r potentials, but the
sheer number of bodies can make the problem difficult. Fluid mechanics involves
solving the Navier-Stokes equations which is simple for small systems, but not for large
systems such as the global climate. Quantum dynamics can in principle be simplified by
decomposition into orthogonal eigenstates, but for some systems a large number of the
latter may be needed. Interactions between particles complicate the Hamiltonian, such
that for the general case only a few degrees of freedom can be modeled at a time.
There are many challenging dynamical problems in physics, and biological physics is no
exception. Problems exist at a macroscopic scale in dealing with viscous flow, heat and
mass transfer, and thermodynamics within organisms and in their interactions with the
environment. On smaller length scales one encounters diffusion, Brownian motion,
active motility, charge transport, and many other phenomena. At the level of single and
aggregated molecules lie systems large enough that the number of degrees of freedom
can be problematic yet small enough to be dominated by thermal fluctuations. At an even
smaller level photochemistry, electron and proton transfer, phonons, isomerization, bond
breaking, polarization, and other quantum mechanical phenomena occur which are
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