# Learning with Errors and Extrapolated Dihedral Cosets

@article{Brakerski2017LearningWE,
title={Learning with Errors and Extrapolated Dihedral Cosets},
author={Zvika Brakerski and Elena Kirshanova and Damien Stehl{\'e} and Weiqiang Wen},
journal={ArXiv},
year={2017},
volume={abs/1710.08223}
}
• Published 23 October 2017
• Computer Science
• ArXiv
The hardness of the learning with errors (LWE) problem is one of the most fruitful resources of modern cryptography. In particular, it is one of the most prominent candidates for secure post-quantum cryptography. Understanding its quantum complexity is therefore an important goal. We show that under quantum polynomial time reductions, LWE is equivalent to a relaxed version of the dihedral coset problem (DCP), which we call extrapolated DCP (eDCP). The extent of extrapolation varies with the LWE…

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It is shown that under quantum polynomial time reductions, LWE is equivalent to a relaxed version of the dihedral coset problem (DCP), which it is called extrapolated DCP (eDCP); the extent of extrapolation varies with the LWE noise rate.

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