Zeev, ZPE is a measurable quantity (see, e.g., http://www.aip.org/enews/physnews/1999/split/pnu433-1.htm ). In that sense, it's a "fact" as good as, or even better, than the existence of the PPT. And, no, I wouldn't attempt to twist your words, at least in a premeditated manner. <ggg>