Abstract
A short story about the origins of Magnus Expansion, why we got involved and how it led us to meet Geometric Integration. We present a biographical draft of Wilhelm Magnus, a sketchy discussion of what is the expansion which carries his name and a derivation of the formalism equations. We explain the important feature that makes the expansion an appropriate tool to develop Geometric Integration schemes.
2010 Mathematics Subject Classification:
Acknowledgments
The authors thank an anonymous referee for the very constructive comments.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Notes
1 Biographical details with no specific reference are taken from one of the following sources: (https://mathshistory.st-andrews.ac.uk/Biographies/Magnus/, https://de.wikipedia.org/wiki/HansHeinrichWilhelmMagnus) and some personal recollections of Magnus in [Citation3].