Re: [Phys-L] thermodynamics of open systems

[John Denker <jsd@av8n.com>]

On 07/17/2012 01:51 PM, Bob Sciamanda wrote:
> But John, the whole point of Carl's paper is that TdS is NOT ALWAYS equal to Q (or dQ).

I'll let Carl speak for himself ... but if that was the point, it
would have sufficed to write a far shorter and simpler paper.

On 07/15/2012 02:37 PM, Carl Mungan wrote:> (Try hard not to get hung up on
> > terminology, unless that *really* impedes understanding in your opinion.)

Maybe we are (despite our best efforts) getting hung up on terminology.

AFAICT when people write "dQ" there are only two things it could mean:
  a) dQ = the derivative of Q
  b) dQ = abusive shorthand for T dS

If there are additional possibilities, I have no idea what meaning was
intended.

In case (a), please explain why you think Q exists (except in trivial
cases).

In case (b), please explain why it would not be better in every way
to write T dS instead of dQ.

If there are other possibilities, I have no clue what they might be, so
please explain.