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Some Problems with the Dirac Delta Function: Divergent Series in Physics

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A Correction to this article was published on 14 March 2022

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Abstract

The completeness relation for the eigenfunctions of a self-adjoint operator generally involves a divergent series or integral. In this paper, we show, using the eigenfunctions of the infinite square well as an example, that these divergent objects can be interpreted as distributions. This should be obvious since the right-hand side of these completeness relations is the Dirac delta function but the direct calculation of the right-hand side can be very laborious, but instructive.

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Acknowledgements

The authors would like to thank Professors Luiz Nunes de Oliveira and Walter Felipe Wreszinski for discussions and clarifications about the content of this paper. The authors acknowledge partial financial support from CNPq.

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Correspondence to Oscar J. P. Éboli.

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Amaku, M., Coutinho, F.A.B., Éboli, O.J.P. et al. Some Problems with the Dirac Delta Function: Divergent Series in Physics. Braz J Phys 51, 1324–1332 (2021). https://doi.org/10.1007/s13538-021-00916-5

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  • DOI: https://doi.org/10.1007/s13538-021-00916-5

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