NetNews Usenet Archive 1992 #20/NN_1992_20.iso/spool/sci/physics/14234

Text File | 1992-09-08 | 3.7 KB | 75 lines

Newsgroups: sci.physics
Path: sparky!uunet!cs.utexas.edu!convex!seas.smu.edu!vivaldi!aslws01!aslws01!terry
From: [e-mail] (Terry Bollinger)
Subject: Re: Did electric/magnetic symmetry "break"?
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Date: Mon, 7 Sep 1992 05:28:22 GMT
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In article <[e-mail]>
[e-mail] (John C. Baez) writes:

> Honest, I took at look at Terry's strange number 63 and did a quick
> check to see if it was the fine structure constant over 2, which it
> wasn't.  But if he meant 68.5 then I guess it's okay...

Yes, the number I was referring to was roughly 68.5, the value first
derived by Dirac as a result of his spin quantization argument for the
Dirac monopole.  I did it from memory, and apparently transposed a "3"
for and "8" (based on visual similarity, most likely).

Very, very interesting conversation, and I'm most appreciative of it.

By the way, I make no pretense of being a group theorist, although I do of
course have some grasp of the basics (abstract algebras were undergrad for
CSc at my alma mater).  So don't expect too many comments from this direction,
at least not in real time.  But I'm archiving it all, I assure you...


[A bit of dull (& needless) personal history follows.  Feel free to skip!]

The genesis of the question that back (way back) in eighth grade I came up
with an argument for the existence of something I called "S-electrons" and
"N-electrons," based on the (faulty) observation that since a high-energy
gamma passing through the intense electric field around a large nucleus could
be converted into an electron and a positron, why couldn't the very similar
magnetic component generate equivalent magnetically charged particles if it
passed through an extremely intense magnetic field?

The idea was totally off-base, of course.  I did not realize at the time
that the particle pairings go deep into the structure of space itself, or
that momentum passing was what made the electric field critical, not whether
it was "electric" or "magnetic."  Nor did I even realize the need for
quantization of angular momentum and its commensurate implication of a fairly
serious asymmetry between the size of the charges.  (I did have a lot of fun
analyzing the strange spin interaction implied by having both electrically
and magnetically changed particles, however.  I just never realized it had
to be quantized.)  So to compound my misunderstanding of the pair formation
process, I also naively assumed that electric and magnetic charges could
have the same magnitude -- which is simply not possible unless you do major
violence to Planck's constant.

(Ever try to do a literature search on Dirac monopoles in a small-town
library in Missouri?  It was mostly luck that I finally uncovered the term
"monopole" in Time magazine and immediately thought "Uh-oh!  Some guy named
Dirac beat me to the punch by about 40 years!" :-)  )

Anywho, I finally dug out the error of my ways, but have never been fully
satisfied about the broader question -- as in, why the heck IS there a ratio
of 68.5-to-1, and why IS space so biased towards particles with the lesser
charge magnitudes?  Why that tantalizing, beautifully symmetrical interplay
of two fields that are so very much alike in a photon (lurking there to trap
nosey eighth graders!), yet such a drastic difference in how that lovely
construction breaks down when you add in a world full of electrons and such.

So it's a bit late, but thanks.  I look forward to munching (somewhat slowly
I fear) through the discussions.

                Cheers,
                Terry Bollinger