Published by the Department of Computer Science, The University of Chicago.
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Abhranil Chatterjee
Department of Computer Science and Engineering
Indian Institute of Technology Kanpur
Kanpur, India
abhranil AT cse DOT iitk DOT ac DOT in
We revisit the main result of Carmosino et al [CILM18] which shows that an $\Omega(n^{\omega/2+\gamma})$ size noncommutative arithmetic circuit size lower bound (where $\omega$ is the matrix multiplication exponent) for a constant-degree $n$-variate polynomial family $(g_n)_n$, where each $g_n$ is a noncommutative polynomial, can be ``lifted'' to an exponential size circuit size lower bound for another polynomial family $(f_n)$ obtained from $(g_n)$ by a lifting process. In this paper, we present a simpler and more conceptual automata-theoretic proof of their result.
Submitted December 3, 2023, revised February 15, 2025, published April 14, 2025.