2005 ) Lecture 5 : PCP
نویسنده
چکیده
2 Powering Stage (Sketch) 2.1 Parameter Effects In this section, we will be sketchy about some details. Entering the powering stage, we have an input constraint graph denoted (G, C). G is an a (n, d, λ)-expander, with λ < d universal constants, and the constraints are over some fixed constant alphabet Σ = Σ0. Our goal is to produce a new constraint graph (G′, C ′) with a larger gap. We will denote parameters of (G, C) (e.g. size) in the input without a prime, and constraint graph parameters of (G′, C ′) in the output with a prime (e.g.. size′). Our goal for gap′ is as below:
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