,
PLZ READ PART 1 BEFORE THIS
later, comparing both the clocks.. the clock in the aeroplane showed billionths o fsecond time more. We can think this is not such a big issue But as the distance increases, it means... when compared with another planet at distance of 1 million loght years from our earth.. 1 year here may equal to an hour there in that planet.
,
Isaac newton said that time is an arrow and it moves straight in a singledirection. But Einstein said that the time is like a river. He said the time moves fast and slows down as well at some place... with little turns, twists, whirlpools and would also get divided into channels.
The time will be slow at the place where a strong gravitational field exists. That is why the time in the atomic clock got slowed down. One single black hole will have the gravitational force thousands of times greater than that of the earth.
,
When the age of you and your friend is 20 years... When you get in to the spaceship alone, going near the black hole in a year and circulating it once... Then by the time when you return to the earth, your friend may turn 80. BUT WILL BE 21 YEARS OLD. That means you traveled into the future. THAT IS THE TIME TRAVEL.