In my previous article, we discussed about the Worm Holes. Tiny Wormholes are present everywhere and it may be possible to grab one and make it large enough. But it won’t last much longer as it would get destroyed under the strong feedback loop of radiations. Therefore, it can’t be used as a time machine. This doesn’t defy the time travel.
[alert type=blue ]Time travel is possible; if not in past through wormholes, we can still travel to the future.[/alert]
Black Holes
Global Positioning System (GPS) is a network of 31 Satellites in orbit around the Earth. These are used for satellite navigation but they also prove that time runs faster up on them, as compared to Earth. [highlight color=#263852 ]The satellites have a very precise atomic clock but it drifts forward a billionth of a sec every day and system has to correct this drift as this would disrupt the whole GPS system and will make every GPS device on Earth go out by 6 miles a day.[/highlight] It’s not a problem with the clock, the reason for this is that time on satellites runs faster than the time on Earth and this extraordinary effect is due to the gravity of the earth. Albert Einstein gave the theory that gravity wraps the time and slows it down. [highlight color=#263852 ]Heavier the object is, more is its gravitational field, slower the time will be near it.[/highlight] This effect is the key to open the door of time travelling to the future.
This time drift in satellites is a bit too less for the time travel but if instead of Earth, we bring an object which is billion times larger than it, like the heaviest object in the Milky Way i.e. the black hole, which is present at the centre of the galaxy about 26,000 light years from Earth, it will become a different story.
Black holes are so massive that even light cannot escape. It is wrapped in a sphere of darkness, 50 million miles in diameter. [highlight color=#263852 ]Black Holes have a dramatic effect on time; they slow it down far more than anything in this galaxy.[/highlight]
If we could send a spaceship far enough, we could harness this ability to travel to the future. The spaceship will have to be on the right trajectory and speed, so that it can prevent falling into somewhere it can never escape. If they get it right, the spaceship will be pulled into an orbit of diameter 30 million miles and its speed would be enough to keep it from falling. [highlight color=#263852 ]If we observe the spaceship from earth, we will observe that each full orbit will take 16 min but for the people on the spaceship, time would be slowed down by half i.e. for every 16 min orbit, they will only experience 8 min.[/highlight] So if they return to the earth after 5 years according to them, 10 years would have passed on earth. On returning, the crew will find that people on earth have aged 5 years more than them.
Until now, this is not practical but black holes have a great advantage over wormholes that it doesn’t provoke paradoxes and it won’t get destroyed into itself. But it is pretty dangerous and it also doesn’t take us too far into the future.