Integer Addition and Hamming Weight

John Y. Kim

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arXiv · 1503.01170

Integer Addition and Hamming Weight

John Y. Kim

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Abstract

We study the effect of addition on the Hamming weight of a positive integer. Consider the first $2^n$ positive integers, and fix an $\alpha$ among them. We show that if the binary representation of $\alpha$ consists of $\Theta(n)$ blocks of zeros and ones, then addition by $\alpha$ causes a constant fraction of low Hamming weight integers to become high Hamming weight integers. This result has applications in complexity theory to the hardness of computing powering maps using bounded-depth arithmetic circuits over $\mathbb{F}_2$. Our result implies that powering by $\alpha$ composed of many blocks require exponential-size, bounded-depth arithmetic circuits over $\mathbb{F}_2$.

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John Y. Kim. 2015-03-04. Integer Addition and Hamming Weight. https://arxiv.org/abs/1503.01170

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