Such a means of transportation as a time machine is today an invention of science fiction writers. Most representatives of the scientific world, with the exception of a very small number of people who think outside the box, consider her appearance impossible. And there are more than enough reasons for this.
There are only three main arguments against the existence of a time machine. The first is that one of the fundamental physical principles is violated - the principle of causality. Indeed, observations of the world show that the events that happened today do not in any way affect what happened yesterday. This principle has never been refuted in the entire history of mankind.
The second argument is that when traveling in time, the appearance of so-called "paradoxical cases" is possible, when the outcome of an event is not just not determined, but in general, it is not clear how an event that has already occurred could have happened. An example of such a paradox is the so-called “grandfather's paradox”. Its meaning is that someone, having invented a time machine, flew into the past and there killed his grandfather. Then a simple question arises: how could he then be born and invent a time machine if his grandfather, from whom the parents of the unlucky inventor descended, died without leaving offspring?
Well, the third argument is the following: the facts of the trips themselves have not yet been observed. Despite all the seeming frivolity of this argument, it is actually the main one. After all, if sooner or later the time machine is invented, then someday someone will surely fly into the past and somehow "inherit" there.
On the other hand, a detailed analysis of each of these arguments leads to its inconsistency. For example, considering the principle of causality, we are talking only about our Universe, about the space-time continuum given to us. And for more than a hundred years it has been known that our three-dimensional dimension is far from the only one, that if we consider a space with a large number of dimensions, then cases are quite possible when the principle of causality in spaces with a smaller number of dimensions is even violated.
As for the "grandfather's paradox", then everything is not easy. There is a theory according to which any event gives rise to a number of different options for its further development, moreover, each of them occurs, as it were, simultaneously, but already in different Universes. Despite the seeming absurdity of such a statement, it is neither physically nor logically consistent. Moreover, it has been proven mathematically.
To put it in a very primitive language, when we think whether or not to go to the store for bread, already at this moment our world splits into two: another Universe appears in which we, for example, do not go to the store. Well, or we go, if we did not go in our "ordinary" Universe. The same situation occurs with the murderer of his grandfather: at the moment of his sending into the past, he finds himself in an "alternative" Universe, where he practically never existed. He was not even born in it, since he killed in it someone who could contribute to his birth.
That is, from the point of view of science, the considered arguments do not give the right to assert that the existence of a time machine is impossible. But the third argument, about the absence of traces, is the one that is of the greatest interest.
Promotional video:
The interest lies in the fact that any researcher who has dealt with this issue is faced with a very unpleasant picture: there is no real evidence of time travel, however, there are a huge number of fakes, forgeries, or incorrect interpretations of this or that phenomenon or event.
There are dozens of so-called "irrelevant artifacts" that simply could not have appeared at that time. For example, modern devices and tools that have grown into fossils, or items of clothing, or descriptions of the achievements of the future in historical chronicles thousands of years ago. Naturally, absolutely all such "proofs" are either made very clumsy, or their appearance is reasoned from the point of view of modern science.
In general, there is a picture of deliberate falsification and the official refutation that followed it very quickly. It seems that this idea (of the consequences of time travel) is being deliberately discredited; otherwise it is simply impossible to name the hype raised at each such manifestation.
Naturally, no one will take seriously the recently found "petrified mobile phone" with cuneiform on the buttons. But when an approach to any such manifestation of temporary inconsistencies is a priori considered as a fake, this cannot but raise questions …
Meanwhile, all the clearest evidence of the possibility of time travel, as they say, lies on the surface. It is only necessary to analyze not the garbage that fell out of the pockets of these travelers, but things that are more significant, although, it would seem, less noticeable.
Many people, using the benefits of civilization, do not even think about their origin or about what principles are the basis for the work of certain modern means of comfort, be it some kind of household devices or social principles.
If we simply analyze the world around us, then we can come to the conclusion that almost everything that will determine our way of life and way of life was invented relatively recently. Indeed, if we take electricity, for example, then humanity has been using it for no more than 150 years. Or, universal suffrage is also an achievement of only the last century. And so on … The most surprising thing is that few people have questions about how we did without all this for almost all of our history.
And this is where the main mistake of such a study lies. In fact, all relatively recently implemented "modern" ideas were conceived by humanity a very, very long time ago. And only the imperfection of the technical level of development and the general degree of education of mankind did not allow to do this earlier.
Despite the widespread opinions about the development of mankind not as a species, but as a civilization, one very interesting conclusion can be drawn: for most of our history, in simple terms, we have been "marking time", and only for two periods the thought of mankind has made significant leaps … And these periods have nothing to do with our time. The first of them lasted about a hundred years and was from us a very long time ago - it is 4-5 centuries BC. The second was relatively recent; it is often called the Renaissance period.
It was during these periods that mankind achieved maximum progress in the history of knowledge of the world and scientific achievements. Let's just look at what was invented at that time and who were the people who provided humanity with the very achievements, without which its current state was not as "advanced" as it is now.
The ideas given to mankind by ancient Greek philosophers and scientists were advanced not only for their time. Their relevance has not lost its significance now. For example, Democritus was the first who not only substantiated the materiality of our world, but also introduced into physics such a concept as an atom - the smallest indivisible particle of matter that has its properties.
His ideas were developed by Epicurus, who explained the structure of the Universe and the ways in which energy and matter interact in it. Ancient mathematicians, Pythagoras and Archimedes laid the foundations of modern analysis, geometry and number theory.
As for the ideas of humanism and rationalism, where would our world be without the thoughts of Socrates? The foundations of modern statehood were laid by Aristotle. Universal suffrage, its subtleties and consequences (not just revolutionary, but, one might say, a heretical idea for the slave system) was first proposed by Plato. And what our way of thinking would represent without the cynics, such as Diogenes and the Stoics, such as Zeno, is better not to imagine.
All these people taught humanity not just some applied ideas, for example, how to calculate the hypotenuse using known legs, they showed how to conduct any research, how to plan any activity in order to achieve the correct results.
Inevitably, the question arises: where did so many ideas come from at that difficult time? It is also interesting that most of their speakers were not just contemporaries, but also residents of practically the same area. Well, it's somehow strange: then there was nothing, and then suddenly, in less than a century, almost EVERYTHING appeared. This progress is difficult to explain by natural causes. As a rule, such phenomena occur when artificial attraction of "outside personnel" is made. One would assume that we are dealing with aliens, but somehow too well-created ideas suit us, humans. Consequently, their authors, most likely, were also people. Perhaps people from the future.
A similar picture took place during the Renaissance, when the first attempts were made to implement the ideas of the ideas of the philosophers of Antiquity. And there were no less revolutionary ideas at that time: it is enough to recall Nicolaus Copernicus with his heliocentric system of the world or Leonardo da Vinci, whose talent was so diverse that many people still doubt his human nature.
Thus, looking at the revolutionary nature of the ideas that arose during these periods, it can be assumed that all these progressive ideas were not just invented from scratch. The possibility is not excluded that their carriers were "abandoned" from the future in order to accelerate the progress of our civilization. And the footprints of travelers are not at all in the artifacts left by them, they are everywhere around us.
Who knows, perhaps our Universe is the result of an experiment by some "Institute of Time", which has set itself the goal of improving the existence of mankind. Perhaps our world is not perfect, but who knows how much less cute it would be if not for such actions …