English

Refuting spectral compatibility of quantum marginals

Quantum Physics 2025-11-26 v4 Mathematical Physics math.MP Optimization and Control

Abstract

The spectral variant of the quantum marginal problem asks: Given prescribed spectra for a set of overlapping quantum marginals, does there exist a compatible joint state? The main idea of this work is a symmetry-reduced semidefinite programming hierarchy that detects when no such joint state exists. The hierarchy is complete, in the sense that it detects every incompatible set of spectra. The refutations it provides are dimension-free, certifying incompatibility in all local dimensions. The hierarchy also applies to the sums of Hermitian matrices problem, the compatibility of local unitary invariants, for certifying vanishing Kronecker coefficients, and to optimize over equivariant state polynomials.

Keywords

Cite

@article{arxiv.2211.06349,
  title  = {Refuting spectral compatibility of quantum marginals},
  author = {Felix Huber and Nikolai Wyderka},
  journal= {arXiv preprint arXiv:2211.06349},
  year   = {2025}
}

Comments

27 pages, 1 figure, 2 tables. v2: added proof of completeness. v3: clarified further applications. v4 final version