{
  "abstract": "Preparation contextuality is often manifested operationally through a quantitative advantage over preparation-noncontextual models in information-processing tasks, yet quantum theory typically falls short of perfect success. Here we introduce a parity-oblivious Hidden Matching task that instead yields an all-vs-nothing manifestation of preparation contextuality. Alice encodes an $n$-bit string so that her message reveals no information about any input parity other than the two-bit parities. Bob, given a perfect matching on the input positions, must output an edge of the matching together with the parity of its two bits. A quantum protocol using a single $\\lceil\\log_2 n\\rceil$-qubit message satisfies the parity-obliviousness constraint and succeeds with certainty. We prove that no preparation-noncontextual model achieves perfect success for any even $n\\ge6$. The result holds for arbitrary ontic state spaces and assumes neither outcome determinism nor measurement noncontextuality. For $n=6$ and $n=8$, the optimal noncontextual success probabilities are $4/5$ and $3/4$, respectively, while asymptotically the optimal noncontextual success probability is $1/2+Θ(1/\\sqrt n)$. Our asymptotic upper bound follows from a Fourier-analytic sum rule derived via hypercontractivity on the Boolean hypercube. The resulting separation is qualitative rather than merely quantitative: quantum theory achieves perfect success, whereas preparation-noncontextual models cannot. We aslo show that at $n=8$ the noncontextual bound remains $3/4$ even when Bob is restricted to just suitable $4$ of the $105$ possible perfect matchings, bringing the effect within experimental reach.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.34964",
  "author_total": 7,
  "authors": [
    {
      "name": "Jayashree Karmakar"
    },
    {
      "name": "Rafiuddin Gazi"
    },
    {
      "name": "Biswadeep Chatterjee"
    },
    {
      "name": "Subhendu B Ghosh"
    },
    {
      "name": "Anandamay Das Bhowmik"
    },
    {
      "name": "Ananya Chakraborty"
    },
    {
      "name": "Manik Banik"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/65rd508ahymrd.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.34964",
  "fulltext_url": null,
  "id": "65rd508ahymrd",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.34964",
  "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 Applications"
    ]
  ],
  "openalex": "W7214784086",
  "pdf_url": "https://arxiv.org/pdf/2609.34964",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-28",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/65rd508ahymrd.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2609.34964",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.34964"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "All-vs-Nothing Operational Manifestation of Preparation Contextuality",
  "title_text": "All-vs-Nothing Operational Manifestation of Preparation Contextuality",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/65rd508ahymrd",
  "venue": "arXiv",
  "versions": []
}