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arXiv · 1804.04050

Boolean functions with small spectral norm, revisited

Tom Sanders
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Abstract

We show that if $f$ is an integer-valued function with spectral norm at most $M$ then there are subspaces $V_1,\dots,V_L$ and signs $\sigma_1,\dots,\sigma_L \in \{-1,1\}$ such that $f=\sigma_1 1_{V_1} + \dots + \sigma_L 1_{V_L}$ where $L < \exp(M^{3+o(1)})$. This note extracts out the argument from arXiv:1610.07092 to the model setting of $\mathbb{F}_2^n$. The hope is that it will clarify the arguments of that paper.

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Tom Sanders. 2018-04-11. Boolean functions with small spectral norm, revisited. https://doi.org/10.1017/s030500411800035x

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