Time travel can only be done into the future, not into the past.
JAKARTA – There are many films and novels that tell about time travel (time travel). Such as “Back to the Future”, “Star Trek”, “Time Traveler Wife”, “Predestination”, and many more. However, can humans really time travel?
Astrophysicist from Ohio State University, United States, Paul Sutter said, humans can time travel. This is closely related to Albert Einstein’s theory of relativity, which states that time depends on how fast humans move.
Sutter added, to travel time humans need a very large rocket plane. Unlike what sci-fi films depict, time travel is much simpler than expected.
“The faster you move in space, the slower your time on Earth. We have measured this with atomic clocks on jet aircraft as evidenced by GPS satellite technology in order to get precise precision,” said Sutter, quoted from Space.
This was shown by one of the NASA astronauts Scott Kelly who stayed on the International Space Station for one year. Upon returning to Earth, Scott is six minutes younger than his twin brother, Mark. This proves that those in space move faster than humans living on Earth and their time in space is slower than on Earth.
Another astronaut who has lived in space for 879 days, Gennady Padalka also said the same thing. In the book by physicist J. Richard Gott “Time Travel in Einstein’s Universe”, Padalka said, Earth is 1/44 second faster than expected. So it can be concluded, every astronaut who goes into space is a time traveler.
Even so, time travel can only be done to the future, not to the past. Sutter explained that mathematical calculations on relativity in general have several scenarios in which one could go back in time. However, these scenarios violate the rules of physics, such as requiring a negative mass or a long cylinder that rotates indefinitely.
“Why is general relativity able to time travel to the past, but physics makes no sense? We honestly still don’t know,” said Sutter.
Another theory surrounding time travel involves wormholes and black holes. Physicist Stephen Hawking once said this theory to Daily Mail in 2010. He said that the more spaceships revolve around a black hole, the time they will be there will be much shorter than people on Earth and they will feel the time travel.
“Imagine them circling a black hole for five years, ten years elsewhere. When they return (to Earth), everyone on Earth will be five years older than them,” he said at the time.
Even so, the theory of wormholes or black holes is still not completely certain. Because until now, both theories still require further research.