Classical Heisenberg model

In statistical physics, the classical Heisenberg model, developed by Werner Heisenberg, is the n = 3 {\displaystyle n=3} case of the n-vector model, one of the models used to model ferromagnetism and other phenomena. == Definition == The classical Heisenberg model can be formulated as follows: take a d-dimensional lattice, and place a set of spins of unit length, s → i ∈ R 3 , | s → i | = 1 ( 1 ) {\displaystyle {\vec {s}}_{i}\in \mathbb {R} ^{3},|{\vec {s}}_{i}|=1\quad (1)} , on each lattice node.

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