1-dimensional Ising model
Model: Consider a system with spins in a row.
The energy of the system will be given by
Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle U=-K\sum _{i=1}^{N-1}S_{i}S_{i+1}} ,
where each variable Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle S_{j}} can be either -1 or +1.
The partition function of the system will be:
Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle Q_{N}=\sum _{\Omega ^{N}}\exp \left[-K\sum _{i=1}^{N-1}S_{i}S_{i+1}\right]} ,
where represents the possible configuration of the N spins of the system.
to be continued ...