Gene Fuller wrote:
"the intensity varies between a maximum value Imax = 4I1, and a minimum
value Imin = 0"

Yes, that's essentially what I have been saying. The peak
intensity (irradiance) can be double the intensity of
the combined intensity of both superposed waves.

What B&W *don't* say is anything about two 1 watt waves interacting,
waves exhibiting constructive and destructive interference, cause and
effects relationships, or even energy conservation.

Eugene Hecht calls the last term in the irradiance equation
the "interference term". He talks about "total destructive
interference" and "total constructive interference". The sign
of the interference term indicates whether the interference
is destructive (-) or constructive (+).

All of those are things written by more casual writers, such as Hecht,
Melles-Griot, and the FSU Java dudes. There is nothing wrong with that
type of explanation for simple illustration, but it runs out of gas when
trying to support detailed analysis. One quickly ends up with silliness
such as waves that are launched and then cancel destructively within a
short (but undefined) distance. None of that nonsense occurs if one
simply applies the standard analysis techniques such as used by B&W.

Exactly what nonsense are you referring to? Please be specific. It
is difficult to defend myself from assertions of "nonsense" with no
specific allegations.

I gather from the above that wave cancellation due to superposition
is against your religion. Since all impedance discontinuities cause
reflections, exactly how and why do those reflected waves cease to
exist? Please be specific.
--
73, Cecil http://www.w5dxp.com