#Kinta_Magna_Ho also

If a fictional train can travel around the Earth seven times in a second, it will gain momentum around the velocity of light ... It is believed that if a passenger rises in that train and at that pace if he travels for seven days, then after 7 days of departure from the train See, they have passed 50 years of earth.
Now my question is

1. What was 7 days for 7 days? Was it 7 days for the train passengers, which is actually 50 years equivalent to Earth?
2. Why do train passengers get older? That means, even after passing 50 years, why do not they grow old?
3. What is the time Has any of our lives gone? Or 50 years have passed and already?

You find the answer? Try a little bit.