🚀 go-pugleaf

sichase@csa1.lbl.gov (SCOTT I CHASE) writes:

>In article <1992Nov09.192052.25358@bas-a.bcc.ac.uk>, ucap22w@ucl.ac.uk (Martin S T Watts) writes...

>>balanced - why can't you? For another thing, they are not. The one thing that
>>you give Einstein credit for is something he probably never said. As Hermann
>>Bondi has pointed out [Physics Bulletin _38_ (1987) p62], in all known physical
>>processes energy and mass are in fact conserved separately. Energy has mass
>>is a more useful statement than energy and mass are equivalent.

>Maybe so, in all physical processes known to Hermann Bondi!  But any 
>student who has spent two days in a particle physics class knows better.

Any student who's spent two days in a particle physics class knows better than
Hermann Bondi? Now there's a sweeping statement.  :-)

(And if you think that, say, positron-electron annihilation is an example of
the destruction of mass, then think again.)

>And how clever of you to reference a magazine so obscure that even *I*
>couldn't find it, with all the resources of the University of California
>Library system at my disposal.  I am told by our local LBL physics librarian
>that Physics Bulletin was a cross between the APS bulletin with it's
>abstracts, and a small-scale Physics Today, with newsy items, appointments,
>obits, that sort of thing.  It has been replaced by Physics World.  The
>U.C. Library, which saves office memos and old toilet paper, never bothered
>to keep its copies of Physics Bulletin.

It wouldn't surprise me if American Universities were turfing out copies of
J. Phys. A! I only included the reference in case people doubted the
authenticity of my claim - I hadn't thought people would go to the trouble
of looking it up. I dug out the original article, though, and found the 
following recommended reading, in case you're interested:

Warren, JW 1976 "The mystery of mass-energy" Phys. Educ. _11_ p52-54 and
letter _11_ p453-4

Bondi, H 1965  Relativity and Common Sense (London: Heinemann) pp72-108, 155-9

Rogers, EM 1960  Physics for the Enquiring Mind (Princeton: Princeton University
Press and London: Oxford University Press) pp403-6

>So I guess that the wisdom of Hermann Bondi is just lost to me...

Well, I hope not. You'd do well to look out this article if you sincerely think
that energy and mass are interconvertible - it's a very common misconception.
The article's published by the Institute of Physics, so it shouldn't be 
impossible to get hold of.

Martin Watts.