In 2029, humanity was almost wiped out by nuclear war and a smart computer called Skynet ruled over planet Earth. The computer is able to defend itself and think ahead like humans, even beyond it. Similar to humans too, Skynet creates damage on earth.
Finding fierce resistance from a human named John Connor, Skynet sent a T-800 robot to quell human remains that were deemed threatening. A restaurant waitress becomes the main target of murder by T-800. Later, the servant will give birth to John Connor in the future. John Connor also did not stay silent, he turned to send his best soldiers to 1984 to protect his mother from T-800.
The above fragment of the story comes from the film The Terminator (1984), a thriller that presents a slick journey of time. The play, played by Arnold Schwarzenegger, is part of the science fiction tradition that often discusses time travel through future technological achievements.
There are many science fiction films that present other time travel elements, including Looper (2012), Interstellar (2014), Predestination (2016), to the old and no less legendary films such as the Back to the Future (1985) film trilogy.
Released a year after The Terminator, Back to the Future presents the story of time travel using a car that has been modified by a genius scientist named Doc Brown. Marty McFly, a friend of the scientist, tried this plutonium-powered time machine back to November 5, 1955.
Stepping back again, in the realm of science fiction novels, the work of Herbert George Wells titled The Time Machine (1895) neatly narrates as well as popularizing the concept of time travel by using a vehicle. The term time machine that made Wells, in fact until now used to refer to a time-traveling vehicle.
In the development of the 21st century, the concept of time travel continues to haunt scientists. The great physicist Albert Einstein, through the general theory of the famous relativity, states that the passage of time might be realized through tunnels “wormholes” that connect different layers of space and time.
Last March, two scientists Benjamin K Tippett and David Tsang helped add to the list of scientists who continue to study the possibilities of time travel.
Through the article “Traversable acausal retrograde domains in spacetime” published in the journal Classical and Quantum Gravity presents details of geometric arrangement patterns, including physical and mathematical calculations designed to match the workings of a time-traveling machine.
Tippet, Einstein’s general theorist on relativity, had studied black holes and science fiction while on leave from his campus. Together with David Tsang, an astrophysicist at the University of Maryland, Tippet continued the application of Einstein’s general theory of relativity to produce a mathematical model he named TARDIS.
“People consider exploring time as something fictitious and we tend to consider it impossible, because we never actually try it. But, mathematically, it is possible,” said mathematician Ben Tippett told Phys.
According to Tippett, the division of space into three dimensions plus time in separate dimensions is not correct. This pattern makes a series of space and time to be different and not interconnected continuously or in a circle.
As a comparison, the findings proposed by Tippet combine these four dimensions in a circular series of interconnected space and time. Also based on Einstein’s theory, the curvature of the circle of space and time is like a curved orbit on the planet.
Tippett and Tsang’s findings also reject the use of straight-line patterns for time-traveling performance schemes. “The direction of time from the surface of the spacetime also shows curvature. There is evidence to suggest that the closer to the black hole, the slower it moves,” he explained.
Although calculations and theories allow it, Tippett himself doubts that a time-traveling machine can be realized even if it uses the principle of its findings. According to him, the building blocks needed are still a major obstacle, especially the material he calls exotic material to bend time.
Exotic material itself was raised and became popular thanks to the findings of a trio of scientists named David Thouless, Duncan Haldane and Michael Kosterlitz. Reporting from Deutsche Welle, the three scientists conducted their research from the 1970s to the 1980s. They use high mathematical methods to examine unusual phases in the material, including super conductors of electricity, super fluid and also very thin magnetic films.
One of them is Sergei Krivalev, a Russian astronaut who lives in the space station (ISS) for 803 days, 9 hours, 39 minutes. He traveled time to his own future for 0.02 seconds.
Although it is very short, but that is what happened to Sergei Krivalev as the effect of time widening. As quoted from Universe Today, time widening is caused by the difference between gravity or relative speed. Each affects time in a different way.
When astronauts and satellites orbit the earth, their position is slightly farther from the earth compared to the people on earth. Then they experience a widening gravitational time, where the time experienced by astronauts will run a little slower than on earth.
This time difference, however, is very small because the space station like ISS limits the orbital speed to only around 7.7 km / sec. It is different if ISS orbits the earth at the speed of light, around 300,000 km / sec. Thus, an astronaut who lives after 6 months at ISS at the current rate, is only around 0.007 seconds younger than the normal age on earth.
New Scientist magazine in a special edition of Einstein’s theory of relativity, also noted that the possibility of time travel can cause physical paradoxes. For example like this. A person named Fulan who is 70 years old roams back into the past becoming younger. The Fulan then killed his own grandfather who had not had time to be married to his grandmother. Of course the parents of the Fulan will not exist because they have died first. Fulan never finally existed. This is called paradox.
But whatever the debate, it is very interesting to see the progress and evidence that continues to be tested and born in the realm of science. Especially if one by one the obstacles in the lab can be solved.