Autor: Zeev Dvir, Andrej Bogdanov, Amir Yehudayoff, Elad Verbin
Rok vydání: 2013
Předmět:
Zdroj: Theory of Computing. 9:283-293
ISSN: 1557-2862
DOI: 10.4086/toc.2013.v009a007
Popis: Recently Bogdanov and Viola (FOCS 2007) and Lovett (ECCC-07) constructed pseudorandom generators that fool degree k polynomials over F2 for an arbitrary constant k. We show that such generators can also be used to fool branching programs of width 2 and polynomial length that read k bits of inputs at a time. This model generalizes polynomials of degree k over F2 and includes some other interesting classes of functions, for instance k-DNF. The constructions of Bogdanov and Viola and Lovett consist of adding a constant number of independent copies of a generator that fools linear functions (an -biased set). It is natural to ask, in light of our first result, whether such generators can fool branching programs of width larger than 2. Our second result is a lower bound showing
Databáze: OpenAIRE