Quoting Mike Stay <metaweta@gmail.com>:
Is there a general formula for "d/dz" in dimension D?
You are in good company with Paul Dirac and Oliver Heaviside. As long as D is finite, there is no problem, even with a multiply valued complex logarithm. It is the limit that hurts, and for which distribution theory was sort of invented. I recall that in the late forties, Aurel Wintner proved that there are no matrices A and B such that AB - BA = I, the unit matrix. Mark Kac must have read the paper, because he assigned it as a problem in the final examination for his Mathematical Methods course. However, the Physics Department did not disappear in a puff of smoke even if you called A and B p and q. But there *were* those who noticed that something was wrong. - hvm ------------------------------------------------- www.correo.unam.mx UNAMonos Comunicándonos