Time travel is possible
A Columbia professor named Brian Greene, who teaches physics, explains that Einstein provided us with the right information for a time travel journey over 100 years ago. According to Einstein, when you travel into space, the speed at which the ship moves is literally as fast as the speed of light, it turns around and returns, in this sense, the clock marks time slowly and when it returns, it will be the future on planet earth.
The scientist also claimed that just by approaching a truly strong source of gravity, time slows down in space and runs fast on earth, a clear example of such sources being black holes. Greene argued that Einstein’s hypotheses are not out of place at all and that, in fact, there are many other scientists who feel exactly the same way.
Time travel back in time is impossible.
Scientists are sure that time travel into the future is very feasible and can be done sooner than we think, however, the idea of traveling into the past is something that scientists find impossible, although a reference can be made to the wormholes that Einstein himself mentioned during his research.
This wormhole is based on a kind of tunnel, in which you can pass through time and space to reach the past. Its speed is relatively slow, but Greene thinks that if you take one end of the tunnel and accelerate it, its energy or force would be similar to that of a black hole, the difference is that instead of going into the future, we would be going through past times and, at the moment this shortcut stops, it would be stationary just at a different moment from its entry, that is, at a time or year in the past, but unfortunately, this hypothesis is not 100% probable.