sci.physics.relativity

Hi Tom and everyone

In a previous thread I mentioned the inertia of stress. I recently came
across an article on just this topic. Its called



Tom - Please correct me if I'm wrong but to my recollection this was a
something you weren't aware of. . I had posted the comment

> It is a fact that after Einstein's 1905 work he continued on to complete
> his
> study of the mass-energy relation. He made one important discovery and
> that
> was that relativistic mass (and also rest mass) was a function of stress.

and you responded with

>This is the first I have ever seen anyone claim that.

Einstein's work on this suvbject, . what led to the inertia of stress,
was in his paper called "On the Inertia of Energy Required by the Relativity
Principle," A. Einstein, [Annalen der Physik 23 (1907): 371-384]. The
particular section is called "On the kinetic energy of a rigid body in
uniform translation subject to external forces."

There is also an article in Am. J. Phys. from last year on this subject. I
only recently obtained a copy of it. Its similar to Rindler and Denur's
"paradox" paper regarding a capacitor but this one gets into it more deeply

"The inertia of stress," Rodrigo Medina, Am. J. Phys. 74(11), November 2006

The abstract reads
-------------------------------------------
We present a simple example in which the importance of the inertial effects
is evident. The system is an insulating solid narrow disk whose faces are
uniformly charged with equal charges of equal magnitude and opposite signs.
The motion of the system in two different directions is considered. It is
shown how the contribution of energy and momentum of the stress that
develops inside the solid to balance the electromagnetic forces have to be
added to the electromagnetic contributions to obtain the results predicted
by the relativistic equivalence of mass and energy.
-------------------------------------------
I e-mailed a copy of this to you.

If anyone would like a copy of these articles please let me know and I'll
either e-mail it to you or I'll place it on my website for a few days.

Best wishes

Pete