> At 10:59 PM 7/22/02 -0700, [EMAIL PROTECTED] wrote: > > >Entropy is not quite a physical quantity -- rather it is on the > >slippery edge between being a physical thing and a philosophical > >thing. If you are not careful, you will slip into a deep epistemic > >bog and find yourself needing to ask "how do we know what is > >knowable, and what is the whichness of why?" > > > >To avoid such deep waters, know where your entropy is coming from.
Right. Then David Honig wrote: > > We agree on your substantive points re RNGs, I think, I join in the agreement. > but you're interestingly wrong here. I don't think jamesd's point was wrong. One could quibble about some of the wording, especially if it were taken out of context, but the passage as a whole makes an important, valid point. > Entropy is a physical quantity, it even figures into chemistry. Yes, it is a physical quantity. Yes, it enters into chemistry. But it also contains an element of subjectivity. For a careful discussion of what entropy is, including the element of subjectivity, see http://www.monmouth.com/~jsd/physics/thermo-laws.htm#sec-second-law > The physics-of-computation people (Bennett? Landaur? etc) Charles H. Bennett and Rolf Landauer. > have written about thermodynamics & information. Not to mention Leo Szilard, Ed Fredkin, Wojciech Zurek, and others. > Modulo Chaitin-type mindgames about measuring it :-) Chaitin's work is profound and well-regarded. Referring to it as "mindgames" is, well, nothing but name-calling and won't advance the scientific discussion. If anybody has a thoughtful objection to Chaitin's work I would be extremely interested to hear it. > Anyway we're cryptographers, not philosophers, so we should > be safe.. A lack of understanding of what entropy is has gotten more than one cryptographer into trouble. --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]