English

#P-hardness proofs of matrix immanants evaluated on restricted matrices

Computational Complexity 2025-11-21 v3 Representation Theory

Abstract

We establish the #P\#P-hardness of computing a broad class of immanants, even when restricted to specific categories of matrices. Concretely, we prove that computing λ\lambda-immanants of 00-11 matrices is #P\#P-hard whenever the partition~λ\lambda contains a sufficiently large domino-tileable region, subject to certain technical conditions. We also give hardness proofs for some λ\lambda-immanants of weighted adjacency matrices of planar directed graphs, such that the shape λ=(1+λd)\lambda = (\mathbf{1} + \lambda_d) has size nn such that λd=nε|\lambda_d| = n^\varepsilon for some 0<ε<120 < \varepsilon < \frac{1}{2}, and such that for some ww, the shape λd/(w)\lambda_d/(w) is tileable with 1×21 \times 2 dominos.

Keywords

Cite

@article{arxiv.2103.04934,
  title  = {#P-hardness proofs of matrix immanants evaluated on restricted matrices},
  author = {Istvan Miklos and Cordian Riener},
  journal= {arXiv preprint arXiv:2103.04934},
  year   = {2025}
}

Comments

Accepted for publication at Theoretical Computer Science