Lecture 15 : Pseudorandomness for Logarithmic Space
نویسندگان
چکیده
In the last lecture, we discussed a recursive construction of a pseudorandom generator that is based on expanders: the INW generator. In this lecture we will show that the INW-generator with a suitable instantiation of an expander family produces pseudorandomness for machines that run in logarithmic space. We also introduce Nisan’s generator, which is a pseudorandom generator that has a recursive structure that is slightly different from, but related to, the recursive structure of the INW-generator, and which employs hash families instead of expanders. We begin with a description of the class of algorithms that we want to produce pseudorandomness for.
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