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FOCS

2004

IEEE

2004

IEEE

In this work we give the first deterministic extractors from a constant number of weak sources whose entropy rate is less than 1/2. Specifically, for every > 0 we give an explicit construction for extracting randomness from a constant (depending polynomially on 1/) number of distributions over {0, 1}n , each having min-entropy n. These extractors output n bits, which are 2-n close to uniform. This construction uses several results from additive number theory, and in particular a recent one by Bourgain, Katz and Tao [BKT03] and of Konyagin [Kon03]. We also consider the related problem of constructing randomness dispersers. For any constant output length m, our dispersers use a constant number of identical distributions, each with min-entropy (log n) and outputs every possible m-bit string with positive probability. The main tool we use is a variant of the "stepping-up lemma" used in establishing lower bound on the Ramsey number for hypergraphs (Erdos and Hajnal, [GRS80])....

Related Content

Added |
20 Aug 2010 |

Updated |
20 Aug 2010 |

Type |
Conference |

Year |
2004 |

Where |
FOCS |

Authors |
Boaz Barak, Russell Impagliazzo, Avi Wigderson |

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