  We compute the regularized temperature for a spacetime foam model, consisting
on S^4 instantons, in quantum gravity. Assuming that thermal equilibrium takes
place with some amount of radiation - with thermal fields in the SU(2)xU(1)
gauge theory - we obtain the remarkable result that the squared value of this
temperature exactly coincides with the electroweak coupling constant at the
energy scale of the gauge bosons W. This is consistent with the classical ADM
result that the electrical charge should be equal to its finite gravitational
self energy.
