Re: 31 bit pseudo-random number gen in C, C++ & dsPIC assembly code

From: Mike Amling (
Date: 10/08/05

Date: Sat, 08 Oct 2005 21:24:37 GMT

John E. Hadstate wrote:
>>It's not an unfortunate name collision, they're the same
>>thing (if possibly scaled differently). There's a Richard
>>Feynman book on the thermodynamics of computation that
>>explains this, and other concepts that seem really twisted
>>but really aren't after you think hard enough about them*.
> They can't be quite the same thing since thermodynamic
> entropy measures a property of physical systems while
> information theoretic entropy measures a property of
> something that is a figment of our imaginations (a useful
> figment, to be sure, but "bits" have no physical
> manifestation and are not constrained by the laws of
> physics).

   Claude Shannon didn't pick the term 'entropy' by coincidence.
Thermodynamic entropy and cryptographic entropy are both the same
function of the probabilities of a system being in each of its possible

--Mike Amling