A 3-query PCP over integers

  • Authors:
  • Venkatesan Guruswami;Prasad Raghavendra

  • Affiliations:
  • University of Washington, Seattle, WA;University of Washington, Seattle, WA

  • Venue:
  • Proceedings of the thirty-ninth annual ACM symposium on Theory of computing
  • Year:
  • 2007

Quantified Score

Hi-index 0.00

Visualization

Abstract

A classic result due to Haastad~hastad established that for every constant ε 0, given an overdetermined system of linear equations over a finite field Fq where each equation depends on exactly 3 variables and at least a fraction (1-ε) of the equations can be satisfied, it is NP-hard to satisfy even a fraction (1/q+ε) of the equations. In this work, we prove the analog of Håstad's result for equations over the integers (as well as the reals). Formally, we prove that for every ε,δ 0, given a system of linear equations with integer coefficients where each equation is on 3 variables, it is NP-hard to distinguish between the following two cases: (i) There is an assignment of integer values to the variables that satisfies at least a fraction (1-ε) of the equations, and (ii) No assignmenteven of real values to the variables satisfies more than a fraction δ of the equations.