In this regard, Brian Greene, professor of physics and mathematics at Columbia University, says that there are two types of time travel - past or future. But he believes that between the two, the journey into the future would be more feasible. Why?
Einsten also said this more than a century ago. According to the genius, if we reach space and travel at the speed of light, time would be harder for us. So when we return to Earth, we realize that we have reached the future, although it has not been as long for us.
Moreover, if we stood next to a powerful source of gravity - such as a neutron star or a black hole - and approached its edge, time would slow down harder for us compared to those on Earth. Thus, returning to Earth would presuppose, once again, that we will have traveled in the future.
"Not transportation in the future is the controversial part," Greene said. "Any scientist who knows what he's talking about agrees that it's possible to go into the future. Problems arise when we talk about travel in the past. That might be. achievable if we use the concept of wormholes also discovered by Einstein ".
These wormholes are a kind of bridge-shortcut between two locations. If the entrances to two of these holes are altered in any way (for example, if we place them next to a black hole) then time will no longer pass in the same way in both. Thus, if we entered a modified hole, we would not only travel to another place, but also to another period.