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arXiv · 2503.05528

Improved Two-source Extractors against Quantum Side Information

Jakob Miller·Martin Sandfuchs·Carla Ferradini
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Abstract

Two-source extractors aim to extract randomness from two independent sources of weak randomness. It has been shown that any two-source extractor which is secure against classical side information remains secure against quantum side information. Unfortunately, this generic reduction comes with a significant penalty to the performance of the extractor. In this paper, we show that the two-source extractor from Dodis et al. performs equally well against quantum side information as in the classical realm, surpassing previously known results about this extractor. Additionally, we derive a new quantum XOR-Lemma which allows us to re-derive the generic reduction but also allows for improvements for a large class of extractors.

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Jakob Miller, Martin Sandfuchs, Carla Ferradini. 2025-03-07. Improved Two-source Extractors against Quantum Side Information. https://arxiv.org/abs/2503.05528

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