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arXiv · 1412.4687

Simulating Hamiltonian dynamics with a truncated Taylor series

Dominic W. Berry·Andrew M. Childs·Richard Cleve·Robin Kothari·Rolando D. Somma
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Abstract

We describe a simple, efficient method for simulating Hamiltonian dynamics on a quantum computer by approximating the truncated Taylor series of the evolution operator. Our method can simulate the time evolution of a wide variety of physical systems. As in another recent algorithm, the cost of our method depends only logarithmically on the inverse of the desired precision, which is optimal. However, we simplify the algorithm and its analysis by using a method for implementing linear combinations of unitary operations to directly apply the truncated Taylor series.

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Dominic W. Berry, Andrew M. Childs, Richard Cleve, Robin Kothari, Rolando D. Somma. 2014-12-15. Simulating Hamiltonian dynamics with a truncated Taylor series. https://doi.org/10.1103/physrevlett.114.090502

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