Re: [Phys-L] OLD --Re: conservation of momentum

[John Denker <jsd@av8n.com>]

On 11/13/2016 04:26 PM, bernard cleyet wrote:
> Pair production:  
>
> > > On Aug 31, 2016, at 9:00 AM, John Denker <jsd@av8n.com> wrote:
> > >
> > > In the early going, the electric field of the two leptons, as
> > > observed from far away, is zero.  That's because they have opposite
> > > charges, at initially the same position.  The reaction on the proton
> > > is initially zero, as it should be.
>
> The leptons overlap 100% ?  

1) Overlap is not the issue; it's irrelevant; see below.
2) For zero-sized particles at zero separation, the percentage
 overlap is zero ÷ zero, so it's undefined as well as irrelevant.

> When they separate?

When they are slightly separated, you have a dipole, made of unit charges
and infinitesimal separation, so the dipole moment is infinitesimal.  The
field at any appreciable distance is zero.

> The leptons are not point objects? 

Doesn't matter.  If you imagine them to be extended objects,
perhaps a thermal de Broglie fuzzball, the dipole moment is
still infinitesimal.