I'm studying QM out of Sakurai's book and on page 95 (equation 2.3.47), he states the Baker-Hausdorff Lemma without proof. I've scoured the internet in search of an elementary proof (i.e. one that does not rely on lie algebras, etc.), but have come up empty. I was wondering if anyone knew of a place I could find a proof online.(adsbygoogle = window.adsbygoogle || []).push({});

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# Baker-Hausdorff Lemma

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