On Fri, Nov 14, 2014 at 5:23 PM, meekerdb <[email protected]> wrote:
> "The numbers of ways the system could have gotten to the way it is" isn't > the usual formulation If you want to say that Entropy is proportional to the number of microstates that produce the same macrostate then it's also proportional to the number of precursor states. > and I think it's ambiguous. In general there are arbitrarily many > possible histories and different possible starting points. > Unless you're talking about hypothetical new physics there are not arbitrarily many previous states that could have produced the present state, just a astronomical number. > Boltzmann's formulation was the logarithm of the numbers of possible > states consistent with constraints defining the system, e.g. its total > kinetic energy > Entropy is inversely proportional to work not kinetic energy. A box of gas may have a lot of kinetic energy because all the atoms in it are moving around at high speed, but they're all moving in different directions, Entropy is a measure of how well all that activity can be translated into moving something in just one direction (work). The higher the Entropy the less work you can get out of it with the same heat sink > In the case of a BH the constraints are its classical defining > parameters: mass, angular momentum, and electric charge. > Yes, a Black Hole is the simplest macroscopic thing in the universe, just 3 numbers tells you all there is to know about a particular one; but there are a gargantuan number of ways that Black Hole could have formed, perhaps it was made by putting a lot of sand together in one place, or encyclopedias or too many puppy dogs, it doesn't matter. And that's why Black Holes have such a enormous Entropy. John K Clark Classically there is no finer grained description, so that's what seems to make BH entropy more fundamental that the usual thermodynamic system. > > Brent > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
