LETTERS TO THE EDITORS
Your Number's Up
To the Editors:
In discussion of the Lambert W function (Computing
Science, March–April), Brian Hayes offers as description
of the Euler number e, the limiting value of a compound
As a physical chemist, I would observe that there are a number of
natural decay processes that e well describes, including
first order chemical rate processes, radioactive decay, and
electrical RC circuit behavior.
All of these result from integration over time of the differential
equation, –dX/dt = kX, where X is some
physical quantity (concentration, charge) and k is a rate
constant. The result is X = e(–kt),
leaving out the constant of integration.
Thus, I suggest that e is not merely some useful
mathematical construct, but a description of some widespread natural phenomena.
David M. Wetstone