{
  "abstract": "We give a generic compiler for turning a wide class of device-dependent protocols with trusted state preparation into sequential device-independent protocols. In order for our compiler to apply, the trusted-preparation protocol needs to satisfy certain minimal conditions: having an entanglement-based realization in the first place, and the entanglement-based realization corresponding to the optimal strategy of any non-local game that satisfies a fairly weak rigidity condition. We apply our generic compiler to give sequential device-independent protocols for uncloneable encryption, copy-protection of point functions, and blind randomness expansion. Our technical contribution is a new class of rigidity theorems based on Rényi divergences, with flexible cryptographic applications. They allow our compiler to achieve a constant rate (i.e., the ratio of trusted states prepared to device uses), while tolerating a constant level of noise per device usage. This overcomes a fundamental scaling obstacle faced by previous rigidity theorems for trace distance or fidelity. For the generic sequential case, our proof is based on the sharp-divergence chain rule by Fawzi and Fawzi (2021), which suffices for a constant but fairly low rate. In the special case when the devices retain no memory, we improve the rates by deriving a novel subadditivity property for a modified channel sandwiched divergence, which may be of independent interest. Finally, as a prospect for future improvements, we also prove a chain rule for the iterated-mean divergences from Brown, Fawzi and Fawzi (2021).",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.00444",
  "author_total": 3,
  "authors": [
    {
      "name": "Amir Arqand"
    },
    {
      "name": "Srijita Kundu"
    },
    {
      "name": "Ernest Y. -Z. Tan"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/d7xagn7c1cq9r.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.00444",
  "fulltext_url": null,
  "id": "d7xagn7c1cq9r",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.00444",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "1702|Quantum Information and Cryptography"
    ]
  ],
  "openalex": "W7215742535",
  "pdf_url": "https://arxiv.org/pdf/2610.00444",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/d7xagn7c1cq9r.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:26:03Z",
      "native_id": "2610.00444",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.00444"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Flexible rigidity: Compiling generic trusted-preparation protocols into sequential device-independent protocols",
  "title_text": "Flexible rigidity: Compiling generic trusted-preparation protocols into sequential device-independent protocols",
  "type": "preprint",
  "updated_at": "2026-10-30T12:26:03Z",
  "url": "https://research.draconitic.com/paper/d7xagn7c1cq9r",
  "venue": "arXiv",
  "versions": []
}