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Physical significance of the discrete Heisenberg group

Physics Asked by Thomas Vidick on January 20, 2021

In quantum mechanics, Schrodinger’s position and momentum operators are characterized by the fact that they form a representation of the Heisenberg group $H_{2d+1}$ over $mathbb{R}^{2d+1}$.

Discretizing this group, as did Weyl, gives a Heisenberg group over $mathbb{F}_p$ for all prime $p$, as described here.
In the case $p=2$ this is the group generated by the Pauli matrices $sigma_X = begin{pmatrix} 0 & 1 \ 1 & 0 end{pmatrix}$ and $sigma_Z = begin{pmatrix} 1 & 0 \ 0 & -1 end{pmatrix}$.

The same Pauli matrices happen to generate the algebra of observables for a spin-$frac{1}{2}$ particle.

Is this a pure mathematical coincidence? (If it is not a coincidence, then how does one mathematically distinguish the two situations?) Or is there a physical explanation for this observation that "discretizing the algebra of observables generated by position and momentum in continuous space gives the algebra of observables for a spin-$frac{1}{2}$ particle"?

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