----- Original Message -----
From: "Alberto Monteiro" <[EMAIL PROTECTED]>
To: "Brin-L" <[EMAIL PROTECTED]>
Sent: Wednesday, August 15, 2001 9:32 AM
Subject: Re: Black holes and such
> Dan Minette wrote:
> >
> > (...) For example, if
> > one combines the upper limit for the size of an electron
> > (...)
> >
> What is the definition of the size of an electron?
>
The lower limit for dpdx>h (maybe h-bar, but that just lowers the size limit
by 2*pi). h=~4*10^-15 eVs (electron volt seconds). The maximum momentum
transfer observed in electron-proton scattering is, IIRC, about 200 Gev/c.
Although preliminary observations seemed to indicate some structure at this
level, additional data tends to indicate that this was just a statistical
fluctuation. So, lets use this for an upper limit calculation. 200 Gev/c =
666 eV s/m. So, dx=6*10^-18 m. That is the upper limit to the size of the
electron.
Dan M.
