Re: A question on inelastic relativistic collisions

["L. R. Cartwright (Larry)" <physics@SCNC.CPS.K12.MI.US>]

Thanks, Sam, for your prompt response.

>         The arguments for the formulas I put up were made on the basis
> that heat is not just pure Energy but also carries some momentum.  When
> Einstein and Planck (actually Planck first) made their calculations
> based on the first law of thermo, they required a "fake force" that
> carried the momentum.  However, the first law considers heat to be pure
> energy.

I thought this issue was resolved in the '50s, and the thermo community
decided that we would call energy "heat" only if it was in a state of
maximum entropy, i.e. totally disordered;  i.e. energy becomes heat by
becoming disordered and the net momentum goes to zero.  Ergo, if it's heat
then there's no momentum to consider.  Am I missing something here?

>         D.L. Steinert "An evaluation of relativistic thermodynamics"
> (Ph.D. thesis - 1969 - Mich. State)

I am not far from Mich. State, and should be able to get it there.  Thanks
for this and all the other references.  Another addition to my growing
summer "to do" list.

>         Another reason for so much confusion is trying to correctly
> define heat and work.  Also, what do we consider in the system.  Ott
> only considered a gas, while Planck and Einstein a gas and a container
> (where I believe their force came from)  It is very hard to understand
> so I will let you read up on the material.

Darn, I hoped there'd be a quick and simple answer.  I should have known
better.  I have never been fond of thermo.  It has always seemed like a
field full of ill-defined concepts accompanied by much hand-waving, like
there's something really fundamental we've never quite gotten to.

Any assistance anyone else can give would be greatly appreciated.

Best wishes,

Larry

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Larry Cartwright
Physics, Physical Science, Internet Teacher
Charlotte High School, 378 State Street, Charlotte MI 48813
<physics@scnc.cps.k12.mi.us> or <science@scnc.cps.k12.mi.us>

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~