The real tau-conjecture is true on average

Irénée Briquel; Peter Bürgisser

doi:10.1002/rsa.20926

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arXiv · 1806.00417

The real tau-conjecture is true on average

Irénée Briquel·Peter Bürgisser

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Abstract

Koiran's real $\tau$-conjecture claims that the number of real zeros of a structured polynomial given as a sum of $m$ products of $k$ real sparse polynomials, each with at most $t$ monomials, is bounded by a polynomial in $m,k,t$. This conjecture has a major consequence in complexity theory since it would lead to superpolynomial bounds for the arithmetic circuit size of the permanent. We confirm the conjecture in a probabilistic sense by proving that if the coefficients involved in the description of $f$ are independent standard Gaussian random variables, then the expected number of real zeros of $f$ is $O(mk^2t)$.

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Irénée Briquel, Peter Bürgisser. 2018-06-01. The real tau-conjecture is true on average. https://doi.org/10.1002/rsa.20926

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