Dear Mr. Wales, You've sold us both short! :-) (<--please note smiley, Mr. Poor!) You have assumed that you could not have anything helpful to say about the physics of this situation, so you have also assumed that it cannot be simply explained if one tries hard enough! Since SR pertains only to rulers and clocks, and to the results of measurements made thereby, this should tell us that it is not exactly an inherently complex subject. (If you want one of those, try quantum mechanics!) I believe that the average layman can see that special relativity does not pertain to E=mc^2, and my simple 5-step proof should make a believer out of you. Here is a brief 5-step proof/explanation for the average layman: Everyone agrees that special relativity (SR) has some sort of mass increase,* just as everyone agrees that SR has some sort of time dilation and some sort of rod contraction. The question is, What is physically happening in these three cases? [* a minor technical point, it's really a momentum (which is simply mass x velocity) increase] Since most laymen feel much more comfortable discussing a clock and its rhythm than discussing mass and momentum, and since all three of the above SR effects are alike, it is much better to begin by using a simple clock-rhythm example. Step 1: Picture a single, normally-operating atomic clock that is sitting on a stationary table some where. (In "tech talk," it is continuously at rest with respect to an inertial frame). Step 2: Note the fact that this clock cannot have more than one atomic (internal, time-keeping) rhythm. (A clock that had two or more different "tick rates" would have to be thrown away!) Step 3: Note the fact that observers in different SR frames will find many "different rhythms" for this clock. (Indeed, in SR, one and the same clock has an infinite number of "different rhythms.") Step 4: Reach the unavoidable conclusion that SR's "time dilation" does not pertain to a clock's intrinsic (atomic, in this case) rhythm. Step 5: Apply this same argument to the other two cases (i.e., to the momentum and rod contraction cases), and similarly reach the equally unavoidable conclusion that SR does not pertain to either intrinsic mass or to intrinsic rod length. (Not that anything more is needed, but strength is added to our argument by the fact that each of SR's cases are reciprocal; e.g., I see your clock is "running slow," but you also see _my_ clock "running slow." If we were talking about real (atomic, intrinsic) clock rhythms, then this would clearly be a physically impossible situation, and the same applies to both the SR momentum and rod contraction cases.) At this point, although we have not answered our original question about what was physically happening in these three cases, we have answered the question about what was _not_ happening in these cases, which means that we have answered the important question Does SR pertain to physically real (or intrinsic) characteristics? And we have found that the answer to this question is No. This tells us all we need to know in order to prove our main point that SR does not pertain to the equivalence of real mass with real energy (which is of course stated explicitly by the equation E=mc^2). -----RR----- _______________________________________________ _________________________________________________________________ Instant message in style with MSN Messenger 6.0. Download it now FREE! http://msnmessenger-download.com