Assume a train is moving past a line of men who are standing extremely close to the passing train. Assume two small bombs have been placed on the outside of the train and they just graze the noses of the men standing along the track as they pass. The bombs will explode when light from a flash bulb, placed on the train’s side, equally distant between the bombs, reaches them. An observer on the train standing midway between the bombs observes simultaneous explosions shortly after setting off the flash bulb. Two of the thousands of men, who were standing on the ground right next to each other and right next to the passing train are killed by the exploding bombs. The man near the end of the train dies before the one near the front. They do not die simultaneously because in the line of men’s reference frame, the light flash moving towards the rear of the train explodes its bomb before the bomb at the front of the train explodes. (During the transit of the light towards the bombs, the bomb at the rear of the train has been moving towards the on coming light, while the one at the front of the train was trying to race away from the on coming flash of light.) Note that their “non-simultaneous deaths” is not due to the time for light to travel to any observer - I had the two (now dead) stationary observers stand right next to the bombs when they exploded. If a third stationary observer, is standing mid way between the two that get killed, that third observer would observer them die at different times. (The two delays for him to see them die, due to finite speed of light, are equal.) CONCLUSION: Simultaneous event in one frame are not simultaneous in one moving wrt to it. This is real effect of SRT. It is not due to any delay of light traveling to an “observer” waiting to sees the events. People who dispute SRT often claim that the events are “really” simultaneous in all frames, but only “seen to be non simultaneous.” Events (or clocks) synchronous in one frame are not synchronous in a different frame and “seeing delays” are not the reason for their lack of simultaneity as most opponents of SRT claim. Thus clocks that strike noonday chimes simultaneously in one frame can not strike them at the same time as synchronized clocks are striking noon day chimes in another frame. That is, synchronized clocks distributed about in one frame can not be synchronous with many in another frame which are correctly keeping time in that frame. If the time dilation of SRT is computed and used to adjust the rate of clocks in one frame, it is possible to synchronize any pair of clocks in two different frames, but not all of them, if they are to correctly keep time in their own frame. The reason is simple. A set of clocks that are separated only by space in one frame are separated by a mixture of space and time in the other. Thus clocks at different locations can not be both synchronous with each others in the same frame (keep time correctly) and yet synchronized with all synchronous clocks in another frame. Take your pick, (but only one of the following two): (1)You can have all clocks in two different frames all show the same time (Each has a unique SRT correction to it rate, which depends on the clock‘s location.) but they do not show the same time as clocks that are synchronous in their own frame. (I.e. they are not keeping correct time in their own frame.) OR (2) You can have all clocks in both of two different frames synchronized with others in their same frame, (Keeping correct time in their own frame.) but the clocks in one frame will not be synchronous with the clocks in the other frame. Any comments from people who claim that all clocks in two different frames can both keep time correctly in their own frame and yet be synchronized with clocks in another frame that are all also showing the correct time in their frame? I.e. people who think time is universal for all frames and thus SRT must be wrong.