Note on the derivative of the hyperbolic cotangent
Quantum Physics
2009-11-10 v1 Mathematical Physics
math.MP
Abstract
In a letter to Nature (Ford G W and O'Connell R F 1996 Nature 380 113) we presented a formula for the derivative of the hyperbolic cotangent that differs from the standard one in the literature by an additional term proportional to the Dirac delta function. Since our letter was necessarily brief, shortly after its appearance we prepared a more extensive unpublished note giving a detailed explanation of our argument. Since this note has been referenced in a recent article (Estrada R and Fulling S A 2002 J. Phys. A: Math. Gen. 35 3079) we think it appropriate that it now appear in print. We have made no alteration to the original note.
Cite
@article{arxiv.quant-ph/0301073,
title = {Note on the derivative of the hyperbolic cotangent},
author = {G. W. Ford and R. F. O'Connell},
journal= {arXiv preprint arXiv:quant-ph/0301073},
year = {2009}
}