Debating theories: Can you really travel in time?

From the invention of the wheel to the exploration of space, humanity has been willing to transcend its limits and conquer the unknown. One of these unexplored frontiers is the domain of time. Can we travel in time, as science fiction writers imagine? Is it a fantasy born of our desire to correct past mistakes and foresee future challenges?

The concept of time travel has captivated humanity for centuries, in literature, philosophy and, more recently, in the field of physics. Various theories try to explain how this trip would work and if it is possible.

In this article, we will explore some of the main postulates that attempt to answer these questions. We will delve into the ideas of contemporary physics and address the philosophical aspects of time. Without further ado, let’s begin our journey!

Theory of relativity and time travel

In the 20th century, Albert Einstein’s theory of relativity revolutionized our understanding of time and space. According to these postulates, both concepts are intertwined in what Einstein called “space-time.” And here comes the interesting part: relativity theory holds that gravity can bend space-time.

In simple terms, it is possible for the presence of a massive object like a planet or star to warp the space-time around it. This means that time passes more slowly near a massive object compared to an area with lower gravity. This phenomenon is known as time dilation and is confirmed by numerous experiments.

So if gravity affects the passage of time, Would it be possible to bend space-time in such a way as to create a shortcut, a faster path from one point to another? This hypothesis leads us to the concept of wormholes.

Wormholes: shortcuts through space-time

Physics speculations regarding time travel arise from the supposed existence of wormholes. Is about a kind of tunnel through space-timea shortcut that, in theory, allows us to travel instantly from one place to another or from one moment to another.

In essence, it would be like folding a sheet of paper in half and punching a hole through it: although the two points are far apart on the flat sheet, they are very close if the paper is folded.

The idea of ​​wormholes comes from solutions to Einstein’s equations, but there is no experimental evidence for their existence. Furthermore, as the book Time Travel in Einstein’s Universe: The Physical Possibilities of Travel Through Time points out, If they existed, there would be enormous technical challenges in using them for time travel..

One of these would be the need for as yet unknown forms of matter, called “exotic matter”, to keep the wormhole open.

Thus, although the theory of relativity does not explicitly prohibit time travel and seems to offer theoretical mechanisms for it, we still need to be able to travel in time as portrayed in science fiction. In this regard, a publication by Physical Review supports the probability that there are many impediments by which the universe ‘protects’ itself from such travel.

Philosophical reflection on time travel

Beyond scientific discoveries and theories, Philosophers play a crucial role in shaping our understanding of time and the journey is through it.

They have raised important questions that help explore the possible implications and paradoxes of the idea of ​​this fascinating journey. Our ways of understanding the phenomenon will vary if we conceive time as a linear or multimodal development.

Temporal paradoxes: a dilemma for time travel

As pointed out in a work by Language, Quantum, Music, one of the most debated questions surrounding this trip is that of temporal paradoxes; The best known is that of the grandfather, proposed by the journalist and science fiction writer René Barjavel in 1943.

If you travel back in time and accidentally kill your grandfather before your father or mother were born, then you could not have existed. to make that trip. This creates a contradiction, since both events (you perpetrating the crime and your birth) cannot happen at the same time.

Some scientists and philosophers argue that This paradox shows that the trip to the past, logically, is impossible and, therefore, impossible in fact. Others, however, suggest that temporal paradoxes would be avoided if certain conditions are met, as in the “many worlds” interpretation of quantum mechanics.

Time travel and the “multiverse”

The theory that there are many worlds is widely exploited in current cinema, through films like Everything at once everywhere. This theory maintains that every time a certain decision is made, the universe divides into two different branches, giving rise to a multiplicity of possible universes.

As an arXiv paper points out, this would produce phenomenal universe inflation, suggesting that Our world would consist of infinitely exponentially large parts, each one behaving as if it were a separate universe.

If we take this proposal into account and return to the grandfather paradox, there would be no contradiction in traveling to the past and, by accident, avoiding our birth. The past to which we travel would constitute a different dimension from which we depart.

This would resolve the paradox, although it would make it impossible to return to our true dimension.since every modification we make in the world would multiply realities.

However, as highlighted in a publication in the magazine Nature, it is difficult to test the “multiverse” hypothesis, since no experiments can be performed. These theories operate on a speculative level and, although they feed the imagination and motivate film production, they can hardly be taken as science.

Could we really travel in time?

Although scientific concepts, such as Einstein’s relativity and quantum physics, suggest scenarios where time travel would be feasible, There is no empirical evidence that it can happen. Furthermore, technical obstacles, such as the need for exotic matter and the instability of wormholes, seem insurmountable with our current technology.

Besides, The paradoxes that such a journey entails pose logical contradictions, which suppose the impossibility of traveling through time linearly. The question of whether it is actually possible to travel on it remains, for now, in the realm of speculation.

You might be interested…