Mike; Apparently you still aren't convinced that there is no instantaneous knowledge of distant events. In the 1905 paper, simultaneity par.1, the time of an event is indicated by a clock near the event. The awareness of the event E by a distant observer is always later, due to light transmission time. Thus the distant observer must know the distance to the event E to know when E occurred. Another graphic for the long running saga, 'what did she know and when did she know it'. On the left: Ann stays home. Bill flies away at .6c, reverses direction (instantly) and returns at .8c. The red lines indicate time dilation relative to the A-clock. Bill sends light signals (blue) to Ann at very short intervals to get clock readings. Because B changes direction at At=10 with a corresponding jump of his axis of simultaneity, it is easiest to view the upper part rotated 180° and run the film backward. On the right: While outbound, the last reading is At=4, which Bill assigns to Bt=5, thus calculating td of 4/5=.80, in agreement with SR. While inbound the next reading is At=16, which Bill assigns to Bt=10, thus calculating td of 1.5/2.5=.60, in agreement with SR. Bill observes (analyzes images, and calculates) that the A-clock rate increases from Bt=5 to 10, then decreases from Bt=10 to 12.5. He calculates the speed of A for the middle segment as .2c. The physical cause for the apparent behavior of the A-clock is, sending a signal while moving in one direction and receiving the return signal while moving in a different direction, the same scenario for curved or accelerated motion. Since the initial conditions require constant clock rates for both, the strange behavior of the A-clock results from Bill's altered perception. Motion of the observer cannot alter distant processes, but can alter his perception. Notice: Bill does not know that At=4 when Bt=5 until Bt=11. Bill does not know that At=16 when Bt=10 until Bt=12. No instant knowledge. Please Register or Log in to view the hidden image!