Quantum Rounding

Rajiv Krishnakumar; William Zeng

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arXiv · 2108.05949

Quantum Rounding

Rajiv Krishnakumar·William Zeng

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Abstract

We introduce new rounding methods to improve the accuracy of finite precision quantum arithmetic. These quantum rounding methods are applicable when multiple samples are being taken from a quantum program. We show how to use multiple samples to stochastically suppress arithmetic error from rounding. We benchmark these methods on the multiplication of fixed-point numbers stored in quantum registers. We show that the gate counts and depths for multiplying to a target accuracy can be reduced by approximately 2-3X over state of the art methods while using roughly the same number of qubits.

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Rajiv Krishnakumar, William Zeng. 2021-08-12. Quantum Rounding. https://arxiv.org/abs/2108.05949

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