Would you like to take a trip down your parents’ era or the future? Most definitely yes!
Not only for the joy of living in the past or have a glimpse into the future once but also to go back in time to change your action and decisions. No one would deny that getting a chance into visiting the past or the future is an exciting and appealing opportunity. But is it actually possible?
The move Back to the Future made us believe in the idea of time travel. Although it made it look extremely easy using a flux capacitor hidden in a DeLorean sports car and 12.1gigawatts of electricity but the fact it time travel isn’t that easy. For centuries probably, researchers have tried to find a way to travel back or forward into time. However, so far there hasn’t been a travel-enabling gadget or device developed. So, does this mean Time Travel isn’t possible? But then, we have heard so many people claim to have time traveled. There are scientists like Albert Einstein who theorized that time travel is possible.
Before deciding about whether time travel is possible or not, we need to explore if the concept is for real or is just a myth. So, let’s dig deep and understand what time travel means and if it is possible at all?
Understanding Time Travel:
Time travel can be defined as a departure from a certain time or era and entering another era. It could be the era of the past or the future. The basic idea behind the concept of time travel is to let people believe that they can physically travel across eras. Theoretically, the concept of time travel is based on the assumption that the ordering of events isn’t invariant. It is, basically, a concept of movement between different eras by an object or a person using a device called time machine. The concept of time travel was popularized mainly by a novel titled The Time Machine written on H. G. Wells in 1895. Ever since then, people have been mesmerized by the very idea of traveling back in time or into the future in order to learn more about the events of that era. Moreover, people feel enticed by the idea of time travel as they take it as a chance to change certain decisions or actions that affected their lives in the present. For instance, the Grandfather Paradox is a concept that entails that people can travel back in the past to kill their grandparents to prevent their birth.
Albert Einstein’s Theory about Time Travel:
Albert Einstein was a hugely revered and acclaimed scientist from the twentieth century. Einstein developed the theories of Special and General Relativity. According to Special Relativity Theory, space and time is the same thing and should be called space-time. For anything to travel through space-time the maximum speed limit required is 30,000 km/sec (that is, 186,000 miles/sec). Einstein further noted that light travels through empty space at the same speed limit. As per the special relativity theory, when one moves through space-time closer to the speed of light, time becomes slower for you than for those whom you’ve left behind. The traveler won’t feel this effect until they return.
The theory of General Relativity claims that time passes a lot slower for gravitational field objects like the Earth than for objects away from such fields. Basically, Einstein believed in the phenomenon of time travel and formulated the two theories to present his ideas regarding how time travel was possible.
Wondering how can Einstein’s theory make time travel a possibility? The first way that it can do that is by breaking the cosmic speed limit to move faster than the speed of light. However, this may not work because at this speed the object would need to have infinite mass.
Another way is by forming wormholes. These wormholes will be formed between points in space-time. This method may work for small particles.
Let’s Check out the Conservation Laws:
Sometimes, it is argued that time travel as a concept is a blatant violation of the conservation laws. For instance, sending an object or body having physical mass back in time will resultantly increase the amount of energy existing at that time. Therefore, the mere idea is a violation of the theory of conservation of energy. It is worth noting that the idea of time travel emerged from global conservation law. However, it is the local conservation law that is involved in the relativist invariant formulations. According to local conservation law, the amount of mass within a small volume changes when the mass flows in or out via the surface. Conversely, global conservation law doesn’t approve that object/mass mostly flows in and out via the surface. Instead, it assumed that the mass integrated all over the space and there cannot be a flow within or out of space at infinity. If this condition isn’t met, global conservation cannot occur. Hence, sending stuff/mass back in time hints on some strange happening.
The Connection between Time Travel and Wormholes:
In simple words, wormholes are a hypothetical concept. Einstein believed that wormholes are space-time that complements the field equations of his general relativity theory. If a time machine is developed, it will utilize a traversable wormhole. This wormhole will, ideally, be accelerated at one end. The acceleration speed will be of a considerable fraction, such as the speed of light combined with a high-tech propulsion system. The machine will be brought back to the point of origin. Another way of using the wormhole to travel across time is by exploiting the gravitational force of the object. This involves taking one entry point of the wormhole and moving it within an object’s gravitational field. This field must have higher gravity than the other entry point though. The machine will then return to the position of the other entrance.
In the two methods mentioned here, time dilation is what causes the wormhole’s end that has been moved to age less and become younger than the stationary end. But, we cannot ignore the fact that time will connect differently within the wormhole rather than outside it. Hence, synchronized clocks present at both ends of the wormhole will stay so no matter if the two ends move around or not. So, if a traveler enters the young end then he/she would exit the older end when the traveler is the same age as the young end. A limitation of such a time-traveling device would be that it will go only as far back in time when the machine was initially created.
Time Travel- The Astronauts’ Viewpoint:
An astrophysicist at Ohio State University, Paul Stutter, stated that we are always moving forward into the future, but only one second at a time. If we want to travel to a specific time in the future, we need to travel faster than that.
“Indeed, we can jump forward into the future as much as we want. It’s only a matter of going really, really fast,” says Sutter. Stutter believes what Albert Einstein claimed in his theory of special relativity that time is relative based on how fast you can move.
Stutter further states that the faster we move through space, the slower we will move through time.
“The faster you move through space, the slower you move through time. We’ve been able to measure this with ultra-precise atomic clocks in jet airplanes, and the precision offered by the GPS system needs to take this into account. Sci-fi always seem to require complicated contraptions to jump in time, when all you need is a very large rocket,” explains Stutter.
Astronauts, in a sense, are akin to time travelers. They go into space alive and stay there at times for months. They travel at a speed of 5miles/second, so they move faster in space than we do on Earth. This means when they are on the space station, astronaut age a bit slower than we living on the planet’s surface do. Stutter claims that our universe’s physics rejects this phenomenon but surprisingly, a few equations from Einstein’s general relativity theory can allow time travel into the past.
“When it comes to the past, the mathematics of general relativity does allow a few strange scenarios where you can end up in your own past. But all of these scenarios end up violating other known physics, like requiring negative mass or infinitely long rotating cylinders. Why does general relativity allow past time travel, but other physics always jump in to spoil the fun? We honestly don’t know,” claims Stutter.
What about Scientists?
Science and scientists totally reject the possibility of time travel and regard it as an image or concept popularized by B grade movies. It is claimed that time arrow can flow in only one direction at a place otherwise it wasn’t possible to execute a four-dimensional coordinate system on space-time. Current theory does not endorse the phenomenon of time travel because the universe is functioning in a linear way in every region.
But scientists are still trying to study the phenomenon of time travel to find a possibility. Eastern Mediterranean University, Cyprus’s Ali Övgün claimed in 2015 that wormholes can be possible in dark matter zones. But Övgün is still researching on the possibility and can only offer mathematical proof.
“I hope one day it will be possible to also find direct experimental evidence,” said Övgün.
Stephen Hawking, world-famous physicist, believed in the idea of time travel. Before his death, he was writing about time travel and explained in an interview to The Daily Mail that a black hole can make it possible. In 2010, Hawking wrote that:
“Around and around they’d go, experiencing just half the time of everyone far away from the black hole. The ship and its crew would be traveling through time.”
He developed the M Theory to explain that there are several hidden dimensions in the universe apart from the four dimensions of the space-time.
“Rapid space travel and travel back in time can’t be ruled out according to our present understanding. Science fiction fans need not lose heart: there’s hope in M theory,” said Hawking.
Before his death, Hawking was writing a book on M theory, which was later completed by his family using his extensive personal archives. In the book, there is a whole chapter dedicated to the perils of AI (artificial intelligence), climate change, and some optimistic points about the future. In the chapter, Hawking predicted that in the near future, science will be able to identify a ‘grand unified theory’ that will combine relativity and quantum physics. Hence, humans will be able to travel via the solar system within this century.
However, Amos Iron, a physicist at the Haifa, Israel-based Technion-Israel Institute of Technology rejects the theory of Hawking claiming that a machine circling around a black hole would disintegrate much quickly, even before moving.
Physicists claim that time travel especially into the future is possible but traveling back in time is impossible. According to the Massachusetts Institute of Technology’s professor of quantum mechanical engineering, Seth Lloyd,
“We can travel at different rates to the future. To go into the past and mess around with it, that’s more controversial.”
A real-life example would the Global Positioning System of the satellites. If the GPS system didn’t contain built-in calibrations, the atomic clocks on the GPS would acquire 38 microseconds per day over the terrestrial timepieces. This would obviously affect the accuracy of locations by several miles. The reason for this occurrence is the same, which Einstein described in his theories of relativity, time dilation.
Famous Time Travelers:
Although time travel seems like a distant reality if we consider the claims made by scientists and physicists. However, there are many incidents where someone claimed to have traveled across time or was identified as a time traveler. Some of the most famous of such time travelers are mentioned below:
Charlotte Anne Moberly and Eleanor Jourdain:
Charlotte Anne Moberly and Eleanor Jourdain worked together at St. Hugh’s College in Oxford. Both were interested in spiritualism and wrote a book that created a sensation around the world. In 1911, they released a book titled An Adventure that contained details about their experience when they visited the Palace of Versailles in 1901. They were exploring the extensive gardens at the Petit Trianon when suddenly they met people dressed in outfits from the 18th century. They even claimed that among the people was a woman who starkly resembled Marie Antoinette. They believed that somehow they had traveled back in time and proved their experience with evidence from historical records. At the time, the book received much attention but later on, their claims were regarded as a thing of imagination.
In 1998, John Titor claimed to have arrived from a parallel timeline. Titor said in 2001 that he was from the future (the year 2036) and informed that time travel was invented by General Electric in 2034. He also claimed that he was visiting the past era because he was on a mission to collect a vintage computer, something that was used in 1975 or older. He explained that they needed the computer to debug computers in the future. Titor made several sensational predictions about the future such as the onset of 2nd American Civil War. But most of his predictions so far have been false.
The Stranger at Gold Bridge:
An authentic photograph from 1941 shows a person who is dressed quite differently from the rest of the crowd at the re-opening of the South Fork Bridge, British Columbia. Believed to be a time traveler, the person’s clothing and especially his sunglasses are different from the styles and products available back in the 40s. However, further research revealed that the appearance of the man may not be as unique. The sunglasses’ style was from the 1920s and closer inspection revealed that the man is wearing a knitted sweater and not a printed t-shirt.
In the early 1950s, the story about Rudolph Fentz emerged that later become an urban legend. People believe Fentz was a time traveler. Reportedly, in 1951 a man was hit by a car in New York City and strangely the person was wearing clothing from the 19th century. After some research, it was revealed that the man disappeared in 1876 without any trace. The items that he was possessing at the time of the accident also belonged to the 1870s era. So, it was publicly announced that the person had traveled through time and landed in 1951.
In the past few years, scientists have been trying to find distortions in space-time to identify a way to create workable time machines. Some do agree that wormholes may offer the much-needed shortcut through space-time. However, no matter how interesting these ideas may sound, it is clearly evident that for real-life objects to travel across time is not a possibility. Almost all scientific theories reject the idea of traveling back in time.
But this doesn’t mean that time travel is not possible at all. What if at some point in the future scientists do manage to develop a working time machine. Technological advancements have made many unreal devices that boggle our minds. So, one day it might be possible for us to travel 10,000 years into the future without aging much along the journey. Let’s believe in the myth for the time being until science completely and categorically reject the idea of time travel with some solid evidence.