Paper 2025/639 Original: eprint.iacr.org/2025/639 ↗

Cryptomania v.s. Minicrypt in a Quantum World

Longcheng Li
Qian Li
Xingjian Li
Qipeng Liu
Abstract

We prove that it is impossible to construct perfect-complete quantum public-key encryption (QPKE) with classical keys from quantumly secure one-way functions (OWFs) in a black-box manner, resolving a long-standing open question in quantum cryptography. Specifically, in the quantum random oracle model (QROM), no perfect-complete QPKE scheme with classical keys, and classical/quantum ciphertext can be secure. This improves the previous works which require either unproven conjectures or imposed restrictions on key generation algorithms. This impossibility extends to QPKE with quantum public key in natural settings, which is tight to all known QPKE constructions with quantum public key.

Metadata
Available format(s)
PDF
Category
Foundations
Publication info
Preprint.
History
2026-06-01: last updated
2025-04-08: published
Short URL
https://ia.cr/2025/639
License
https://creativecommons.org/licenses/by/4.0/

BibTeX

@misc{cryptoeprint:2025/639,
      author = {Longcheng Li and Qian Li and Xingjian Li and Qipeng Liu},
      title = {Cryptomania v.s. Minicrypt in a Quantum World},
      howpublished = {Cryptology {ePrint} Archive, Paper 2025/639},
      year = {2025},
      url = {https://eprint.iacr.org/2025/639}
}
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