Before I post this, I want to assure everyone that I am not a conspiracy theorist who doubts Einstein or relativity theory in any aspect. I just don't understand special relativity as well as Id like to and I think having this paradox resolved in my mind will help.(adsbygoogle = window.adsbygoogle || []).push({});

The paradoxes that Ive seen before have usually been resolved with either "One inertial frame undergoes acceleration while the other doesn't" or "events that appear simultaneous aren't actually simultaneous". I cant seem to get either of those to apply here though.

Ok so heres the setup. A train is moving at 0.6c on a track relative to the ground. Hypothetically, an infinite number of synchronized clocks at rest on the ground line the entire length of the track. As the train passes a point A on the track, a clock at rest with the ground reads that the front of the train crosses at 4:55PM. As the train passes point A, a switch is tripped inside the train which causes a bomb in the train to activate with a timer of 5 minutes.

Each one of the infinite clocks lining the track is equipped with a blade that will deploy off the side of the track when the clock reaches 5:00PM. This blade will slice a wire off the side of the train which will deactivate the bomb.

Heres where the paradox arises (at least according to my understanding). From the perspective of the man on the ground, the train is moving at 0.6c and therefore the bomb timer will appear to be moving slower due to time dilation. In this case, when the clocks on the ground reach 5:00PM the slower train bomb clock will read that it still has 1 minute left since its moving at 80% speed. Therefore the blades will deploy in time and the bomb will be deactivated.

Now from the perspective of the guy on the train. He understands that at 5:00PM a blade will cut his wire, but he observes the clocks on the ground as moving slower than the timer on the bomb. Therefore from his perspective, the bomb will tick all the way down to 0 and the clocks outside will still only read 4:59PM. Therefore the bomb will go off before any blades have a chance to cut the wire.

In summary:

A guy on the ground sees his clock as moving at regular speed and the bomb timer on the train moving slowly. 5 minutes of rest clock time results in only 4 minutes of bomb timer time. In this scenario the wire is cut in time and the bomb DOES NOT go off.

A guy in the train sees the bomb timer as running at regular speed and the clock on the ground moving slowly. 5 minutes of bomb timer time results in only 4 minutes of rest clock time. In this scenario the wire is not cut in time and the bomb DOES go off.

Clearly there is a conflict here and I cant seem to resolve it. What am I missing here?

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# Need help resolving this paradox with time dilation

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