Lower Bounds of Algebraic Branching Programs and Layerization

Christian Engels

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arXiv · 2007.06819

Lower Bounds of Algebraic Branching Programs and Layerization

Christian Engels

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Abstract

In this paper we improve the lower bound of Chatterjee et al.\ (ECCC 2019) to an $Ω(n^2)$ lower bound for unlayered Algebraic Branching Programs. We also study the impact layerization has on Algebraic Branching Programs. We exhibit a polynomial that has an unlayered ABP of size $O(n)$ but any layered ABP has size at least $Ω(n\sqrt{n})$. We exhibit a similar dichotomy in the non-commutative setting where the unlayered ABP has size $O(n)$ and any layered ABP has size at least $Ω(n\log n -\log^2 n)$.

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Christian Engels. 2020-09-17. Lower Bounds of Algebraic Branching Programs and Layerization. https://arxiv.org/abs/2007.06819

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