There is no one answer. The dimensions are inferred from the fact that $\left| \psi\right|^2$ represents a probability density. Perhaps the most straight-forward way is to consider the normalizatio...
The most famous formula of this kind is Bloch's $T^{3/2}$ law:
$$M(T)=M_0 \left( 1-\left(\frac{T}{T_c}\right)^{3/2}\right)$$
It is a low-order approximation for the spontaneous magnetization in i...
