Approach to equilibrium
following three simulations explore some of the qualitative properties of macroscopic
systems. Before you actually do the
simulations, think about what you believe the results will be. In many
cases, the most valuable part of the simulation is not the simulation
itself, but the act of thinking about a concrete model and its behavior.
Questions to ponder as you do these simulations include the following:
- Do macroscopic systems exhibit a direction of time? If so, why?
- What is the nature of equilibrium?
- Particles in a box. A simple
Monte Carlo simulation
of particles initially confined to one half of the box. The simulation
shows the approach to a more random state from a specially prepared
state and the importance of fluctuations in equilibrium.
- Three partitions. A
simulation of a Lennard-Jones liquid in two dimensions. The particles
are initially restricted to the middle third of the simulation cell.
- Two partitions. A molecular dynamics simulation of a box divided into two partitions. The particles
are initially restricted to the left half of the simulation cell.
Updated 12 May 2008.