Einstein's Train Metaphor: Explained

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SUMMARY

Einstein's train metaphor, specifically the Relativity of Simultaneity, illustrates that time is perceived differently depending on the observer's frame of reference. In this thought experiment, a person in the middle of a moving train flashes a light, which reaches both the front and rear of the train simultaneously from the train's perspective. However, an observer at a railway station sees the light reaching the rear of the train first, as the rear clock moves towards the light while the front clock moves away from it. This discrepancy highlights the fundamental principle that simultaneity is not absolute but relative to the observer's motion.

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Can you explain Einstein's train metaphor/thought experiment.

Thanks
 
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Are you referring his thought experiment dealing with the Relativity of Simultaneity?
 
Yes, Relativity of Simultaneity
 
it is impossible to discuss here. i will scan and send my hand calculation about this train. in this experiment it was revealed that time is relative for each person :)
 
ErolDynamics said:
it is impossible to discuss here. i will scan and send my hand calculation about this train. in this experiment it was revealed that time is relative for each person :)

Many thanks
 
markf said:
Can you explain Einstein's train metaphor/thought experiment.
Thanks

He explains it himself, here:
http://www.bartleby.com/173/9.html
You could modify his example to a simpler one (IMHO) as follows.

You are in the middle of the train and take a picture with flashlight, light of which reaches the front and rear of the train. These light pulses that are received at the front and the rear of the train are simultaneous by definition in a standard coordinate system in which the train is in rest.

Now suppose that the train was passing a railway station, and there the flash light was also observed. According to the railway station's reference system, while flash light propagated towards the rear, the clock in the rear traveled towards the light; thus this took less time. And while flash light propagated towards the front, the clock in the front traveled away from it, so that took more time. As a result, the light reached the front clock later than the rear clock, according to the time counting of the railway station.

PS. I now see that that is also the way the Wikipedia article presents it, and with pictures; it's really easy.
 

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