#### Motor Daddy

**Valued Senior Member**

http://www.bartleby.com/173/9.html

Einstein says:

"Just when the flashes 1 of lightning occur, this point M' naturally coincides with the point M, but it moves towards the right in the diagram with the velocity v of the train."

"Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash B took place earlier than the lightning flash A."

I contend there is no relativity of simultaneity, that the strikes occurred simultaneously, and that the observer on the embankment and the observer on the train will agree on when the strikes occurred.

There is however a distinction between the simultaneity of the strikes, and when the light from the strikes impacts the observers. I realize the light will hit the train observer at different times, as the train is in motion. Therefore, the observer on the train will be hit by the light from the front of the train before the light from the back of the train reaches him. That is a result of the light from the rear of the train having to travel a greater distance until it impacts the train observer.

The light from points A and B hits the embankment observer simultaneously, as the strikes occurred at both points when the train and embankment points coincided, and he was at the midpoint. The light from each strike traveled the same speed and the same distance to reach the observer. The conclusion from that is that the embankment observer could not have had a velocity, he was at a true zero velocity.

The perceived "relativity of simultaneity" in this example is due to the train observer's failure to acknowledge his own velocity, as is clearly shown with the directional arrow in the example. That incorrect assumption leads him to his false claim that the strikes must have occurred at different times.

edit: The board will not allow me to post the URL to Einstein's example. The example can be found in chapter 9 of Einstein's- Relativity

The Special and General Theory.

Einstein says:

"Just when the flashes 1 of lightning occur, this point M' naturally coincides with the point M, but it moves towards the right in the diagram with the velocity v of the train."

"Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash B took place earlier than the lightning flash A."

I contend there is no relativity of simultaneity, that the strikes occurred simultaneously, and that the observer on the embankment and the observer on the train will agree on when the strikes occurred.

There is however a distinction between the simultaneity of the strikes, and when the light from the strikes impacts the observers. I realize the light will hit the train observer at different times, as the train is in motion. Therefore, the observer on the train will be hit by the light from the front of the train before the light from the back of the train reaches him. That is a result of the light from the rear of the train having to travel a greater distance until it impacts the train observer.

The light from points A and B hits the embankment observer simultaneously, as the strikes occurred at both points when the train and embankment points coincided, and he was at the midpoint. The light from each strike traveled the same speed and the same distance to reach the observer. The conclusion from that is that the embankment observer could not have had a velocity, he was at a true zero velocity.

The perceived "relativity of simultaneity" in this example is due to the train observer's failure to acknowledge his own velocity, as is clearly shown with the directional arrow in the example. That incorrect assumption leads him to his false claim that the strikes must have occurred at different times.

edit: The board will not allow me to post the URL to Einstein's example. The example can be found in chapter 9 of Einstein's- Relativity

The Special and General Theory.

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