{
  "abstract": "Exceptional points (EPs) are conventionally identified through eigenvector coalescence, inaccessible in classical platforms lacking a Hamiltonian spectrum. We introduce classical observable coalescence as a diagnostic identifying EPs directly from physical configurations, and demonstrate it in a known non-Hermitian Ising chain with coupling $J$ and staggered imaginary field $γ$, chosen for verifiability against established quantum results. A mean-field reduction of the Heisenberg dynamics yields equilibrium branches organising into two symmetry-related families whose fusion at the boundary of the EP supersurface $|γ|=|J|$ exhibits the characteristic $\\sqrt{J^2-γ^2}$ branch-point structure and two-sheeted Riemann topology. Crucially, the degeneracy at $γ=0,η=0 $ is shown to be a diabolic point, producing no observable coalescence, establishing the diagnostic as discriminating rather than merely suggestive. An exact Jordan-Wigner and Bogoliubov-de Gennes treatment confirms eigenvector coalescence at the same threshold, and a coupled gain-loss circuit realisation is proposed, establishing classical observables as experimentally accessible signatures of non-Hermitian criticality.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.05877",
  "author_total": 7,
  "authors": [
    {
      "name": "P. K. Nkaimbi"
    },
    {
      "name": "C. A. Mba"
    },
    {
      "name": "A. B. Moubissi"
    },
    {
      "name": "M. R. Kamsap"
    },
    {
      "name": "L. C. Fai"
    },
    {
      "name": "M. E. Ateuafack"
    },
    {
      "name": "M. N. Jipdi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7k8njxx71xv7w.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.05877",
  "fulltext_url": null,
  "id": "7k8njxx71xv7w",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.05877",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "3107|Quantum Mechanics and Non-Hermitian Physics"
    ]
  ],
  "openalex": "W7220662068",
  "pdf_url": "https://arxiv.org/pdf/2610.05877",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7k8njxx71xv7w.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:01Z",
      "native_id": "2610.05877",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.05877"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Classical observable coalescence as a discriminating diagnostic for spectral degeneracies in non-Hermitian systems",
  "title_text": "Classical observable coalescence as a discriminating diagnostic for spectral degeneracies in non-Hermitian systems",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:01Z",
  "url": "https://research.draconitic.com/paper/7k8njxx71xv7w",
  "venue": "arXiv",
  "versions": []
}