Hidden Cosets and Applications to Unclonable Cryptography

@article{Coladangelo2021HiddenCA,
  title={Hidden Cosets and Applications to Unclonable Cryptography},
  author={Andrea Coladangelo and Jiahui Liu and Qipeng Liu and Mark Zhandry},
  journal={ArXiv},
  year={2021},
  volume={abs/2107.05692}
}
In this work, we study a generalization of hidden subspace states to hidden coset states (first introduced by Aaronson and Christiano [STOC '12]). This notion was considered independently by Vidick and Zhang [Eurocrypt '21], in the context of proofs of quantum knowledge from quantum money schemes. We explore unclonable properties of coset states and several applications: - We show that assuming indistinguishability obfuscation (iO), hidden coset states possess a certain direct product hardness… 

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