**Authors:** John L. Haller Jr.

The thermal diffusion of a free particle is a random process and generates entropy
at a rate equal to twice the particle's temperature, R = 2k_{B}T/ℎ (in natural units of information per
second). The rate is calculated using a Gaussian process with a variance of (Δx_{0} + Δp⋅t/m)^{2}. One
would be keen to notice that the solution to the quantum mechanical diffusion of a free particle is
(Δx_{0})^{2} + (Δp⋅t/m)^{2}, however we assume that concurrent to quantum diffusion, the center of the
wavepacket is also undergoing classical diffusion which adds an addition variance in the amount of
(ℎ⋅t/m), making up the difference. Derivations of the variance and subsequent entropy rate are given.

**Comments:** 9 pages

**Download:** **PDF**

[v1] 7 Oct 2009

**Unique-IP document downloads:** 502 times

**Add your own feedback and questions here:**

*You are equally welcome to be positive or negative about any paper but please be polite. If you are being critical you must mention at least one specific error, otherwise your comment will be deleted as unhelpful. *