Re: [Phys-L] Particle physics

[John Denker <jsd@av8n.com>]

On 06/18/2013 02:59 PM, Bill Nettles wrote:

> based on the Standard Model, leptons, quarks,  and gauge bosons would
> (today) be classified as "fundamental."
  ^^^^^^^

That's right -- today.  Or maybe not even.

In any case, remember the proverb: 
            Eight times burned, ninth time shy.

How many times do we need to get burned by this idea
("fundamental") before we decide it's a bad idea?

Specific constructive suggestion:  Just say that the standard
model is based on the following zoo of particles........

Emphasize that this is non-committal about the internal
structure of the specified particles ... just as chemistry 
can build molecules out of atoms, while being non-committal 
about subatomic processes.

That's the general philosophical argument.  The more detailed
physics argument goes like this:
  a) Given that a muon can decay, it seems a safe bet that
   there's "something" going on inside it.

  b) Even when it comes to the most structureless thing we 
   know, the electron, there has to be more to the story.
   The electrostatic self-energy of the electron is still
   an issue.  People have gotten reeeeally good at sweeping
   this under the rug, but there's still a lump in the rug,
   if you know where to look.

   Indeed, this is another one of those things that makes
   a good answer to the student who asks, Why go into
   physics if everything has already been figured out?

   Specifically:  You can in principle measure the mass
   of the electron (and its field, of course) as a function
   of radius.  In principle you could do this by looking
   at the Keplerian orbit of an uncharged test particle.
   If you do this at a radius on the order of the classical
   electron radius or less, you've got a problem, and 
   there's nothing in the standard model that's going
   to bail you out.

   If it turns out to be a string, then it has internal
   structure and internal excited states, i.e. waves
   on the string.