Time Travel: Is It Possible for Humanity to Achieve?

Is it possible to travel through time? The short answer is that you are doing it now as you speed into the future at an amazing pace of one second per second.

However, this isn't the kind of time travel that has inspired a vast genre of science fiction. Over 400 films are listed under the "Movies about Time Travel" category on Wikipedia and have intrigued countless science fiction writers. Characters in popular series such as "Star Trek" and "Back to the Future" get into crazy vehicles and travel back in time or into the future. After stepping back in time, the characters need to consider the consequences of altering either the past or the present by using knowledge from the future. This is where time travel stories and parallel universe theories collide. 

The idea of altering history or seeing the future fascinates a lot of people, but no one has ever shown how to travel back and forth in time like in science fiction, nor has anyone suggested a way to send someone through important epochs without destroying them in the process. Furthermore, as physicist Stephen Hawking noted in his book "Black Holes and Baby Universes" (Bantam, 1994), "The best evidence we have that time travel is not possible, and never will be, is that we have not been invaded by hordes of tourists from the future."

Science Supports the Possibility of Time Travel

Interestingly, science does support some degree of time-bending. For instance, time is suggested to be an illusion that moves in relation to an observer by physicist Albert Einstein's theory of general relativity. When an observer travels close to the speed of light, they will experience time and all of its consequences such as aging and boredom, much more slowly than when they are at rest. Because of it, over the course of a year in orbit, astronaut Scott Kelly aged ever so slightly less than his twin brother who remained on Earth. 

Additional scientific theories concerning time travel exist, such as unique physics related to black holes, wormholes and string theory. But time travel still stays mostly as the subject of an expanding selection of science fiction publications, including comic books, video games, television series, films, and books. 

Albert Einstein Was Not Wrong

In 1905, Einstein created his special relativity theory. It is now regarded as one of the cornerstones of modern physics, along with his later development, the theory of general relativity. It explains the relationship between space and time for objects traveling straight ahead at constant speeds.

The theory is surprisingly simple in its brief form. First of all, there is no "absolute" frame of reference because everything is measured in relation to something else. Second, light travels at a constant speed. It remains constant regardless of the circumstances or the point of measurement. Thirdly, nothing has the ability to travel faster than light.

Now it's true that live time travel emerges from those basic principles. When an observer is moving quickly through space, they experience time more slowly than when they are not.

Real-Life Examples of Time Travel

Humans are not moved toward the speed of light, but they are propelled around the earth at 17,500 mph (28,160 km/h) when they are in the International Space Station. Scott Kelly, an astronaut, was born after Mark Kelly, his twin brother and fellow astronaut. Mark was in space for 54 days, compared to Scott Kelly's 520 days in orbit. The two men's age difference has actually grown as a result of the different rates at which they experienced time throughout their lives. Mark Kelly stated, "So, when I used to be just 6 minutes older, now I am 6 minutes and 5 milliseconds older," during a panel discussion on July 12, 2020.

NASA claims that scenarios involving general relativity might potentially enable time travel. However, those time-travel techniques are not simple to implement physically.

What is Infinite Cylinder Theory?

The astronomer Frank Tipler proposed a mechanism (sometimes referred to as a Tipler Cylinder) that would allow matter with ten times the mass of the sun to be rolled into an extremely long and dense cylinder. A time travel research group called the Anderson Institute named the cylinder "a black hole that has passed through a spaghetti factory."

A spaceship could travel backward in time on a "closed, time-like curve" after spinning this black hole spaghetti a few billion revolutions per minute by following an extremely exact spiral around the cylinder, according to the Anderson Institute. 

The main issue is that the cylinder would have to be infinitely long or composed of an unidentified substance for the Tipler Cylinder to actually exist. Endless interstellar pasta is out of reach for the time being, for now.

Time Donuts Theory Seems Like a Nice Try

Amos Ori, a theoretical physicist at the Technion-Israel Institute of Technology in Haifa, Israel, developed a model of a curved space-time time machine that consists of a sphere of normal matter encircling a donut-shaped vacuum.

According to Ori, the machine is space-time itself:

"If we were to create an area with a warp like this in space that would enable timelines to close on themselves, it might enable future generations to return or visit our time."

Ori's time machine has certain limitations. Initially, time travelers would not be able to go back in time before the time donut was created and constructed. Second, and perhaps more crucially, the creation and building of this machine would be dependent upon our capacity to control gravitational fields, a task that is certainly beyond our current capabilities even if it is possible in theory.

Can Humanity Solve the Problem of Time Travel?

In conclusion, each piece of time-travel fiction crafts its own interpretation of space-time, ignoring one or more scientific difficulties and contradictions to fulfill the narrative requirements.

Some, like Christopher Nolan's 2014 film "Interstellar," give tribute to science. In the film, Matthew McConaughey plays a character who spends a few hours on a planet orbiting a supermassive black hole. However, due to time dilation, those hours appear to observers on Earth as a matter of decades.

So answering the question if time travel is really possible, we can all agree that it is within reach and in the future we might see time travel experimentations taking place but without a doubt, we’ll need much more advanced tech to achieve it. However, we shouldn’t underestimate our current progress on the time travel problem because it’s already in our imagination. There are so many science fiction movies showing it in different ways and the topic itself is something that can be explained and understood. 

“Imagination is everything. It is the preview of life’s coming attractions.” - Albert Einstein.