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A Dual Polynomial for OR

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 نشر من قبل Robert Spalek
 تاريخ النشر 2008
  مجال البحث الهندسة المعلوماتية
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 تأليف Robert Spalek




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We reprove that the approximate degree of the OR function on n bits is Omega(sqrt(n)). We consider a linear program which is feasible if and only if there is an approximate polynomial for a given function, and apply the duality theory. The duality theory says that the primal program has no solution if and only if its dual has a solution. Therefore one can prove the nonexistence of an approximate polynomial by exhibiting a dual solution, coined the dual polynomial. We construct such a polynomial.



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