{
  "abstract": "A spacetime seal, a cryptographic guarantee that a digital event has occurred at an approved location and time, can augment a digital signature with location attestation for legal, financial, and regulatory use cases. In adversarial settings any purely classical realization of such a seal can be spoofed. Quantum position verification (QPV) offers a physics-based solution, exploiting the no-cloning theorem and the no-signaling principle to certify a party's spacetime coordinates. While the feasibility of QPV has been recently shown via entanglement- and coherent light-based protocols, achieving loss tolerance for these schemes substantially increases implementation complexity at metropolitan scales. Here, we introduce and experimentally demonstrate a loss-tolerant QPV (LT-QPV) protocol whose security is independent of channel loss. We prove finite-size security against quantum polynomial-time entangled adversaries in the quantum random oracle model instantiated with cryptographically secure hash functions. Implemented entirely with commercial off-the-shelf components, our system certifies position within 22 minutes of net data collection time against a restricted adversary, with a clear path to real-time certification (<1s) with upgraded hardware. Our architecture, requiring only a single quantum verifier node alongside classical infrastructure, is naturally compatible with metropolitan-area quantum networks, establishing the foundations for scalable, physics-backed spacetime certification as a deployable service.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.23234",
  "author_total": 16,
  "authors": [
    {
      "name": "Wen Yu Kon"
    },
    {
      "name": "Niccolò Bigagli"
    },
    {
      "name": "Andrew Conrad"
    },
    {
      "name": "Taylor Shields"
    },
    {
      "name": "Fatih Kaleoglu"
    },
    {
      "name": "Ignatius William Primaatmaja"
    },
    {
      "name": "Alexander Craddock"
    },
    {
      "name": "RJ Pisani"
    },
    {
      "name": "Mael Flament"
    },
    {
      "name": "Jude Seeber"
    },
    {
      "name": "Omar Amer"
    },
    {
      "name": "Charles Lim"
    },
    {
      "name": "Xinhua Ling"
    },
    {
      "name": "Rob Otter"
    },
    {
      "name": "Kaushik Chakraborty"
    },
    {
      "name": "Mehdi Namazi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2ynq4tq8cd51g.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.23234",
  "fulltext_url": null,
  "id": "2ynq4tq8cd51g",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.23234",
  "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",
      "1702|Quantum Information and Cryptography"
    ]
  ],
  "openalex": "W7214017089",
  "pdf_url": "https://arxiv.org/pdf/2609.23234",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-19",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2ynq4tq8cd51g.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2609.23234",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.23234"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Loss-Tolerant Quantum Position Verification for Metropolitan Area Networks",
  "title_text": "Loss-Tolerant Quantum Position Verification for Metropolitan Area Networks",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/2ynq4tq8cd51g",
  "venue": "arXiv",
  "versions": []
}