Oh, if only it were that simple! Easy to put into the car, time and type losdüsen. 88 miles per hour - whoosh! - We have reached in the distant future - or in a dark past. But as easy as in the science-fiction classic "Back to the Future" time travel is not. Despite the lack of prospects, for example, the stock prices of today in the luggage did yesterday go public, would certainly not lacking. Or repeat the botched dream date with the woman this time and make sure that we not drill all too apparent in the nose. What is the travel time that is in the way? Time but, like space, just another dimension, right?
The brilliant physicist Stephen Hawking has joked times, if time travel were possible, we would have long since overrun by hordes of tourists from the future. But now seriously: One must first differentiate between the travel times in the future and such in the past. First, the simpler: the future. There are actually a relatively clear principle that allows us to look after 3 minutes of our grandchildren. You either climb into a rocket, with the darkest lichtgeschwindikeitsnahen speed through space, or to park the rocket on the edge of a gravity-dripping black hole (hineinzurutschen without, of course). For according to the special and general relativity time passes slower the more the faster you move, or the stronger the gravitational force acting on one. While passing on the earth for your remaining contemporaries a century, shows your own Clock only five minutes. Or even less. The cosmonaut Sergei Krikalev traveled during his 800 days in space in a whole Fünzigstelsekunde the future - but only because we can not produce higher speeds.
looks much more difficult it out when it comes to traveling back in time. There is one small and two large stumbling blocks. The small one is the logic. They argued that if past trips were possible, there would be an irreconcilable paradox:
You could kill his own grandfather,
would that even born never
so would have no one there who could kill the grandfather,
so that born but now would
and would go back in time to kill the grandfather ...
It turns always in a circle, and the universe does not like such contradictions. On this issue there is a surprisingly simple answer - the self-compliance principle . It states that only such course of events are possible, the not contain self-contradictions. When I was thus born, then I can indeed go back in time to kill my grandfather, but I will not make it in some way - either I meet him on or not someone else confused with him (and now know who the mysterious unsolved committed murder, has told the grandfather of the time). And when I travel back in time to find out what you have seen for a mighty unusual flash my neighbors two days ago, then the only explanation for the flash of light that I have caused him to travel through time itself. The causality loop is closed in this way, the world is again consistent.
But the first big stumbling block: how us insignificant patent officer from Bern informed, has each object has its own time (otherwise it would not provide this journey into the future, which relates so well to only one object, possible ). So climb into the time machine to travel so only in the own past - that is, one is younger. The rest of the world, this does not matter, he remains, as it is. To travel into the past "within the meaning of the science-fiction stories, one would have reversed the whole rest of the world put in the time machine (and themselves remain outside), which obviously technically impossible (for more complications resulting from past trips here ).
The biggest problem to travel to the past is this: You can not go into something that does not exist. And time does not exist. Of course, we all have a clock, but time there are not as such. It is a mere construct of our consciousness, a calculating aid, a measure of changes in the world. The physicist Ernst Mach said again: "The time is ... an abstraction to which we go through the change of things", and he is right . , so it is also absurd to ask what it was before the Big Bang - da nothing existed, there was no time, no amount of change or movement of something. "Before the Big Bang" is thus an equally nonsensical sentence like: "North of the North Pole." Since time exists only in perception, one can moreover also measure how fast it goes by a particular sector. Happen in the brain computational processes 100 in 1 second elapses more slowly for this being the time than if the same processes take 10 seconds ("oops, only a short 10 seconds and already enjoys over !..."). Why is the time in old age, with decreasing speed of thought processes demonstrably slower . But if the only time a think of our minds and nothing more, you can not stay in it. One can only slow down the speed or sequence of events (so future trips), but never turn back.
Theoretishe Although physicists speculate about time travel by means of rotating universes or stable worm holes in the curved space-time, but all these are highly controversial and thought-structures, in reality, impossible. We are so caught up in the now. The very fast tomorrow, or "ten-years-later" is. And then the time for us because we think more slowly, too quickly passes. Gather therefore the day!
