Lecture 7 Microstates, macrostates and models

Systems of many microscopic particles following reversible laws of motion have irreversible collective dynamics. The new concepts microstates, macrostates, multiplicity and most likely state will help explaining this apparent contradiction.

We study physical phenomena and do calculations on models of these phenomena. In this lecture we will look at different models of diffusion and of the properties of dilute gases.

Lecture notes part A.

Video on microstates, macrostates and multiplicity. Example: two state model.

(The order of presentation is slightly different this year, so don't worry if the video refers to something you do not remember hearing about. We will get to it!)

As you see you will need some of your knowledge in statistics. Some questions to recap:

Video on multiplicity of 3 models: 2-state paramagnet, random walk and Einstein crystal

 

Video on Matlab calculation of multiplicity of coupled Einstein crystals and corresponding Matlab script

 

Video on Matlab simulation of "heat conduction" between coupled Einstein crystals and corresponding Matlab script

 

Is the development in this movie impossible or just very unlikely?

 

Lecture notes part B

Video on the phenomenon of diffusion

Video on Molecular Dynamics models of diffusion

These are the Lammps input files for the 3D  and 2D MD simulations of diffusion in this lecture. You may run them yourselves.

Video on the random walk and an algorithmic model of diffusion.

These are the Matlab scripts for the two random walks using a for loop and using vectors and the algorithmic model

Publisert 7. sep. 2022 14:13 - Sist endret 7. sep. 2022 14:41