  Due to the nonvanishing average photon population of the squeezed vacuum
state, finite corrections to the scattering matrix are obtained. The lowest
order contribution to the electron mass shift for a one mode squeezed vacuum
state is given by $\delta m(\Omega ,s)/m=\alpha (2/\pi )(\Omega
/m)^2\sinh^2(s)$, where $\Omega$ and $s$ stand for the mode frequency and the
squeeze parameter and $\alpha$ for the fine structure constant, respectively.
The correction to the anomalous magnetic moment of the electron is $\delta
a_e(s)=-(4\alpha /\pi )\sinh^2(s)$.
