Can we go back in time?
In all time travel theories allowed by real science, there is no way a traveler can go back in time to before the time machine was built.
We could travel 10,000 years into the future and age only 1 year during that journey.
However, such a trip would consume an extraordinary amount of energy.
Why is it impossible to go back in time?
The law of causality follows from the fact that nothing can be faster than the speed of light. The law states that the effect of an action can only occur after the cause, which would make time travel into the past impossible.
How can I time travel to the future?
“The mechanism for traveling into the distant future is to use the time-dilation effect of Special Relativity, which states that a moving clock appears to tick more slowly the closer it approaches the speed of light.
How do you build a time machine to the past?
1:How to Build A Time Machine – Paul Davies –