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DOE OSTI · 2537984

Estimating QSVT angles for matrix inversion with large condition numbers

Novikau, I. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000202276700)·Joseph, I. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000255400840)
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Abstract

Quantum Singular Value Transformation (QSVT) is a state-of-the-art, near-optimal quantum algorithm that can be used for matrix inversion. The QSVT circuit is parameterized by a sequence of angles that must be pre-calculated classically, with the number of angles increasing as the matrix condition number grows. Computing QSVT angles for ill-conditioned problems is a numerically challenging task. Here, we propose a numerical technique for estimating QSVT angles for large condition numbers. This technique allows one to avoid expensive numerical computations of QSVT angles and to emulate QSVT circuits for solving ill-conditioned problems.

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97 MATHEMATICS AND COMPUTINGMatrix inversionQSVTQuantum computingQuantum linear system algorithm

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BibTeXRIS

Novikau, I. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000202276700), Joseph, I. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000255400840). 2025-01-22. Estimating QSVT angles for matrix inversion with large condition numbers. https://doi.org/10.1016/j.jcp.2025.113767

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