A Koteljanskii inequality for permanents

Suvrit Sra

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arXiv · 2609.39979

A Koteljanskii inequality for permanents

Suvrit Sra

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Abstract

We prove a permanental analogue of Koteljanskii's inequality. If $A$ is an inverse $M$-matrix that becomes symmetric after a positive diagonal similarity, then $\mathrm{per}(A_{S\cup T})\,\mathrm{per}(A_{S\cap T})\ge\mathrm{per}(A_S)\,\mathrm{per}(A_T)$ for all $S,T\subseteq[n]$, where $A_S$ is the principal submatrix indexed by $S$. The proof expresses permanents as moments of a complex Gaussian vector and uses Ginibre's correlation inequality. Finally, an explicit counterexample shows that symmetry cannot be dropped.

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Suvrit Sra. 2026-09-30. A Koteljanskii inequality for permanents. https://arxiv.org/abs/2609.39979

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