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Finding Exponential Product Formulas of Higher Orders

Naomichi Hatano·Masuo Suzuki
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Abstract

In the present article, we review a continual effort on generalization of the Trotter formula to higher-order exponential product formulas. The exponential product formula is a good and useful approximant, particularly because it conserves important symmetries of the system dynamics. We focuse on two algorithms of constructing higher-order exponential product formulas. The first is the fractal decomposition, where we construct higher-order formulas recursively. The second is to make use of the quantum analysis, where we compute higher-order correction terms directly. As interludes, we also have described the decomposition of symplectic integrators, the approximation of time-ordered exponentials, and the perturbational composition.

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Naomichi Hatano, Masuo Suzuki. 2005-06-02. Finding Exponential Product Formulas of Higher Orders. https://doi.org/10.1007/11526216_2

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