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Fooling Gaussian PTFs via Local Hyperconcentration

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 نشر من قبل Li-Yang Tan
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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We give a pseudorandom generator that fools degree-$d$ polynomial threshold functions over $n$-dimensional Gaussian space with seed length $mathrm{poly}(d)cdot log n$. All previous generators had a seed length with at least a $2^d$ dependence on $d$. The key new ingredient is a Local Hyperconcentration Theorem, which shows that every degree-$d$ Gaussian polynomial is hyperconcentrated almost everywhere at scale $d^{-O(1)}$.



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