Is it possible for us to travel backwards in time and change the course of history? Can we hope that one day we will travel into the future? Today, our expert team will answer these questions as there is probably still enough confusion on this hot topic.
Unfortunately, or most likely fortunately, travelling into the future or back to the past is not possible. If it was possible, believe me, it would be a very unpleasant experience for us.
What Einstein taught us is that there is no absolute time. Experiments have proven him correct. There are only two ways that we can play with time, but it would be unfair to call this game a real time travel. The first way is what Einstein called "Special Theory of Relativity or SR", and the second way is the "General Theory of Relativity or GR". According to the SR, time is relative with respect to the position, and according to the GR time is relative with respect to the position and gravity. If we therefore change our position, time will become relative. Time is also relative for different strengths of gravity. For a photon time freezes. The same is true for an object near enough a black hole. These are both examples of limiting values of position change and gravity strength. We know that it is impossible for a massive object to reach the speed of light (as this would require infinite amount of energy), but it is in theory possible to go near a black hole and slow down our time. However, in reality the tidal forces near a black hole would be so strong that would tear our bodies apart. In addition to that, our only advantage would be that we could go back to Earth or to an other planet, and find them to be far ahead in the future, since time in the meantime, time would flow faster there. However, we can still reach speeds such as the 9/10th of the speed of light, and cause a significant time dilation that will allow us to travel to other galaxies, and still be alive. Or we may even return back to Earth, and have effectively travelled into the future of Earth. With high enough speeds we may travel to other galaxies, millions of light years away. A practical and interesting question that needs to be examined here, is if the human body would be able to survive huge accelerations. However, even with a slow acceleration it will not take too long (compared to a human lifespan) to reach the speed of light. Conclusion: your only practical chance to time travel is to build a fast spaceship !
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