Time travelling is a physical paradox which seems impossible and doesn't make sense as if people could be able to travel back in time, they could easily affect our pasts and if so could happen then our past won't actually be our pasts and may keep on dynamically changing. Secondly, there hasn't been good enough evidence which could support phenomena of time travel, though many people have been observed with very strange stories and happenings none of them have proved to be true at considerable scale.
Though there can be many other supporting statements against time travel still I do believe that the future is here and we are actually messing through the fabrics of space-time. Time that doesn't flow bi-directional, it can only move forward. So if we try to alter its movement and go back to our past and try altering it, doesn't mean that the past of that particular timeline has changed. Instead, a new timeline fabric stretches out in a new dimension with a brand new future. Depending upon the number of alterations over one timeline, the new timelines keep on getting generated and nothing goes back to the past instead, the future changes to a different future.
Since gravity, light and spacetime are connected strongly to each other so there should be very much chances to observe a time traveller in our timeline or universe and so has happened many times, though their confirmations haven't been reported, yet they are pretty much shocking to everyone. So this is a short story about a passenger in Japan who wanted to move to a strange country. When he was asked for his passport he shows a passport which the authorities have never seen before. This makes him even more suspicious. The authorities decide to investigate and ask him to wait in the airport's guest house for some time. To their shock and disbelief, the entire passport format was correct but the country wasn't found in any of their records. When they further tried to investigate by asking him questions, they found that the person himself has disappeared from the room he was residing in!
Though there's still not any confirmed or valid explanation for this incident, there can be very high chances that the person was a time traveller who accidentally travelling between two different time dimensions crashed into our timeline. The person could belong to a dimension very similar to ours, with the same physical location as earth but different continents and countries. These alterings are very well possible in time travelling phenomenon and are quite justified as well. The people who travel back in time are actually not moving back but creating another timeline with a completely different future by just replicating what happened into the past and pasting it over a new future.
Also, there are very well chances that there can be many travellers roaming all around us, watching you read this and watching me write this. Well we surely can't see them as they are fast enough for us, they are travelling at light speeds and according to De-Broglie Hypothesis, due to extremely high speeds, they may be roaming around like matter waves, from dimensions to dimension without even getting noticed to anyone.
Universe has multiple hidden mysteries embedded within, the more we understand its complexity the deeper we dig, the better we understand and realize that how much more we need to dig and know about its working. Time travelling is one of those complex phenomena and surely interesting enough to further research on it and understand it better!
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