Is time travel possible?

Few questions in contemporary culture provoke our curiosity and imagination so much: Is time travel possible?

To answer briefly and directly: yes, and we are doing it right now!

For example, we travel a year between our birthdays, approximately 24 hours between the two days, and we all travel through time at an average rate of one second per second. But it’s not this kind of boring time travel that attracts countless sci-fi fans has produced countless films and literary works related to this genre for decades.

In classic franchises Return to the future, Star wars This Doctor WhoThe characters get on a strange machine and set off towards the past or the future. In these different time periods, they are faced with a series of outcomes that our minds judge will occur if the past is changed or the future is known.

But it will even be possible to use Exploring fundamental aspects of time and space only to discover future consequences of the presentbut also past events?

At the beginning of the last century, Albert Einstein laid the foundations of our modern understanding of time and space with his theory of relativity. In 1905, Einstein developed a limited part of his theory called special relativity. This, along with its later expansion, became one of the fundamental principles of modern physics, the theory of general relativity, first published in 1915.

Special theory of relativity

Explains special relativity Relationship between space and time for objects moving at constant speed in a straight line. The short version of the theory is based on two seemingly simple ideas: first, that everything is measured relative to something else (i.e. there is no “absolute” frame of reference), and second, that the speed of Light is constant and has an upper limit in nature.

Starting from these simple principles, real and measurable time travel emerges: An observer moving at high speed will experience time slower than an observer not accelerating. In other words, the faster you travel, the slower you feel the passage of time.

Although it is not possible to accelerate macroscopic objects to speeds close to the speed of light, scientists have conducted a series of experiments that show this to be true. In one of the most classic, two perfectly synchronized watches are used simultaneously. One of these clocks remains on the Earth, while the other remains on a plane moving in the same direction as the Earth’s rotation.

After the plane flew around the earth, scientists compared the two clocks and found that the clock on the high-speed aircraft was slightly behind the clock on the surface, and the plane’s clock was ticking slightly more than a second slower. every second.

In short, if you want to travel fast in time, speed up! Depending on the quality of your equipment, it would theoretically be possible to travel days, months, decades, or even billions of years into the future. You can then witness the evolution and extinction of humanity, the end of the Earth and the Sun, and the collision of the Milky Way with Andromeda.

The problem is trying to time travel into the past. In this case, we need the full version of Einstein’s theory of general relativity, which is the theory that reveals the relationship between space, time, matter, and energy. Space-time is an integral tissue, and it is matter and energy that deform it and cause changes in this tissue..

famous wormhole

According to the theory of general relativity, the presence of massive objects distorts the fabric of space-time, resulting in time dilation effects. The greater the proximity to the massive body, The greater the temporal distortion, the slower time will pass relative to another observer located further away..

Some specific solutions to Einstein’s equations suggest the theoretical possibility of the existence of wormholes (Einstein-Rosen bridges), transitional structures in space-time that would directly connect two different universes or two distant regions within the same universe.

If these structures could be stabilized and manipulated, it might in theory be possible to use them to travel through time, including the past, which contains some of the most interesting scientific and philosophical paradoxes ever discussed.

Until now and probably for a long, long time into the future, Meaningful time travel will only exist in mathematical possibilities and in the pages of science fiction books.. The discovery and practical manipulation at any level of structures or machines that allow us to travel to the future or return to the past to correct our mistakes will likely remain only in our imagination.