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arXiv · 1808.00250

On the structure and convergence of the symmetric Zassenhaus formula

Ana Arnal·Fernando Casas·Cristina Chiralt
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Abstract

We propose and analyze a symmetric version of the Zassenhaus formula for disentangling the exponential of two non-commuting operators. A recursive procedure for generating the expansion up to any order is presented which also allows one to get an enlarged domain of convergence when it is formulated for matrices. It is shown that the approximations obtained by truncating the infinite expansion considerably improve those arising from the standard Zassenhaus formula.

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BibTeXRIS

Ana Arnal, Fernando Casas, Cristina Chiralt. 2018-08-01. On the structure and convergence of the symmetric Zassenhaus formula. https://doi.org/10.1016/j.cpc.2017.04.004

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