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arXiv · 2311.14044

An Improved Method for Quantum Matrix Multiplication

Nhat A. Nghiem·Tzu-Chieh Wei
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Abstract

Following the celebrated quantum algorithm for solving linear equations (so-called HHL algorithm), Childs, Kothari and Somma [SIAM Journal on Computing, {\bf 46}: 1920, (2017)] provided an approach to solve a linear system of equations with exponentially improved dependence on precision. In this note, we aim to complement such a result for applying a matrix to some quantum state, based upon their Chebyshev polynomial approach. A few examples that motivate this application are included and we further discuss an application of this improved matrix application algorithm explicitly with an efficient quantum procedure.

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Nhat A. Nghiem, Tzu-Chieh Wei. 2023-11-23. An Improved Method for Quantum Matrix Multiplication. https://doi.org/10.1007/s11128-023-04054-6

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