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Re: waves vs. diffusion



----- Original Message -----
From: John S. Denker <jsd@MONMOUTH.COM>
To: <PHYS-L@lists.nau.edu>
Sent: Friday, January 28, 2000 2:54 PM
Subject: Re: waves vs. diffusion



In case anybody missed it, I'll restate it: A parabolic partial
differential equation with real coefficients describes diffusion, not
waves. If you put an "i" in the right place it becomes the Schrödinger
equation which describes waves, not diffusion. Big difference.

If you want to make the S.E. look simple, you can set hbar=1 and c=1 and
mass=1, but you had better not set i=1. No siree.


The SE can be turned into two coupled equations, free of imaginary
quantities. These coupled equations illustrate yet another member of the
family of real, differential "wave equation(s)":

IE., if you substitute into the free particle Sch eq : Phi(x,t) = R(x,t)
+ i*M(x,t) you get two coupled equations for (real) R and M :

(d/dx)^2(R) = dM/dt and (d/dx)^2 (M) = - dR/dt

Bob

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor