= Coincident-point bunching factors
{title2=$g^{(n)}(0)=n!$}
A single-component chaotic Gaussian bosonic field has normalized coincident normally ordered correlation $n!$: every pairing contributes the same product of densities. A same-component fermionic field instead has zero coincident correlations for $n\geq2$ by exclusion. These are state-dependent statements: a coherent bosonic field has factor one, and a single-mode <number state> has $N^{\underline n}/N^n$. Ratios to distant unnormalized correlations additionally require the compared densities to agree and distant correlations to factorize.
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