The modern man is a time traveler in all aspects because mentally, humans project themselves into the past and the future by revisiting their memories. It is through these revising and projecting that humans have managed to invent future and explore possible events with anticipation and desire. Typically, the concept of time machine invokes the imagination of images of that is often used in the science-fiction storylines. But from the general theory of relativity advanced by Albert Einstein, which explains gravity activities on earth, real-life time travel is not just science fiction but could be real (Nahin 289). According to Einstein, it is possible to travel forward in time with no controversy, based on a series of experiments. For example, some physicists have managed to send some tiny particles known as “muons”, which have some resemblance to electrons, forward in time through the manipulation of gravity around them (Hunter 19). The technical feasibility of time travel through a wormhole is real based on the rule of theoretical physics.
A wormhole, which is defined as “a portal through space created by energy fluctuations in positive and negative directions”, was initially proposed as a tool to aid the teaching of the general theory of relativity (James et al. 487). However, today wormhole has developed into a multiuser tool seen as an efficient alternative for time travel. Researchers have made several attempts to achieve observational signatures of wormholes over the last few years, and more scientist are developing an interest in the subject as it has developed into one of the most popular subjects in the field of astrophysics. On his blog post, “How Traveling Back in Time Could Really, Physically Be Possible”, astrophysicist Ethan Siegel explained how it is possible for one to travel back in time through a wormhole (James et al. 487). Similarly, other physicists have also noted how it is possible to travel in the future through the same wormhole. These arguments are based on the principles of Einstein’s theory of relativity. Despite many experiments to prove such possibilities, many have maintained that these are just complex imaginations seen in fiction movies, which carries not a single sense of possibility.
The concept of time-loop
Most physicists have regarded general relativity as the most useful scientific theory ever discovered. According to Al-Khalili (217), its usefulness and beauty “lies in the simplicity, elegance and richness of its mathematical equation.” In what he refers to as time loop, Al-Khalili (218) notes that if one makes a round trip and comes back at the same spot where you started then it will still come back at the same time, then it becomes traveling back in time because the latter shall not have changed much. In this sense, Einstein’s general relativity can allow for the existence of time loops. For example, general relativity had predicted that the region of space-time that surrounds the cylinder can twist around it, and is also likely to contain a time loop.
The concept of time loop can be explained using Interstellar, the 2014 blockbuster movie where the idea of time dilation is narrated to a more advanced level with more realistic science. Christopher Nolan’s movie begins with the hero Coop, who blast off toward the starts, living behind his 10-year-old daughter, Murph. He declares to the daughter, “Time will change for me, it will run more slowly, and when I come back we will compare.” The daughter is also a budding scientist, remarks, “You say science is about admitting what we don’t know.” Cooper takes a near-light-speed and black-hold journey. When he returns, he looks the same with no sign of additional age to his appearance, yet Daughter Murph has grown up and becomes older. Although the film employs some form of special mumbo-jumbo kind of science fiction, it is filled with elements of real science. The movie shows us cryo-beds for deep sleep, speculative imagination but could be very much possible. They also have counter-orbital slingshots for fancy gravitational dynamics, in addition to finding what appears to be one of the ends of a wormhole, which presents a disturbance of space-time.
Nevertheless, questions are still being raised on whether wormhole is real or not. Physics theorist Kip Thorne speculated that a “traversable” wormhole could provide time machine window, with one end acting as a hypothetical opening for entry of a space ship and exiting to the other end. In a study to investigate particular theoretical predictions for static wormholes, Moraes et al (129) report investigative research on the probability of the existence of static wormholes. They define static wormholes as those whose throat radius is viewed as a constant. Their findings suggest that the assumptions could be a possibility and in line with Einstein’s theory.
An experiment to demonstrate that it is possible to transverse Einstein-Rosen Bridge of the eternal AdS black hole via a specific double-trace deformation of the boundary CFTs (Breukelen, Rik and Papadodimas 1). Prior to deformation, the two non-interacting boundary theories were placed in one specific entangled state. But after deformation, shockwaves were created in the bulk. This was done with negative average null energy, meant to slightly shrink the black hole horizon. The process allowed the particle to move through the wormhole from one point to the other. The deformation could also be formulated as a quantum teleportation protocol that exists between the two CFTs. Such successful experiment has given out evidence that horizon’s smoothness of the legendary black hole. Research has also established that traversable-wormhole protocol, based on a time-shifted thermofield state, can lead to experiments that involve time-travel. In certain circumstances, the general relativity can give room for future possibilities when they hover near the horizon for some time, and then fly away to allow the observer to travel to the future. However, Breukelen, Rik and Papadodimas (2) note that this approach is not the best because of its slowness and that it requires big accelerations to move fast and far in time.
Blackhole, gravity, and quantum mechanics relationship
The belief that wormholes could not only exist but also provide room for passage through its tunnel in curved space-time, which connects two distant places, could make travel a real possibility. However, according to Lobo (18), moving to the other side of the galaxy may not still be possible yet because it is not practically useful for humans to travel through. Moreover, it would take longer to pass through these wormholes than to go to the other side of the galaxy directly, hence they are not yet useful for travel space (Lobo 19). Despite this pessimism in the possibility of pan-galactic travel, the potential secret would be to find a way to construct a wormhole for light to travel through, which is an essential step towards the development of the quantum theory of gravity. The quest for black hole information problem, which is based on the theory connecting gravity and quantum mechanics, was inspired by Jafferis’ thoughts about quantum level (Olmo 118). The secret is in the recognition of the relationship between black hole information problem, gravity and quantum mechanics. The inspiration about the new theory is an offshoot of two black holes that were integrated on a quantum level, as formulated in the ER and EPR correspondence equation (Olmo 119). What this means is that the direct connections in a wormhole are longer than that between black holes, hence the former does not provide any shortcut whatsoever. Nevertheless, the theory provides a deeper insight into quantum mechanics. Olmo (126) notes that from the ordinary external perspective, travel through the wormhole is similar to the idea of quantum teleportation with the use of entangled black holes.
In the paradox of grandfather provided by Everett’s multiple worlds in quantum mechanics, the idea of time travel means that one arrives in a different universe from the one they come from, although this is not a “real-time” journey in itself. Arntzenius and Maudlin (169) accepted the interpretation of multiple worlds, which suggests that all possible quantum events could exist in mutually exclusive histories. Arguably, every traveler can experience only one self-consistent history, for travelers to stay in their own world rather than travel to another.
In the explanation of contradictions, Arntzenius and Maudlin (170) held the belief that most of the contradictions appearing for time travel debate are incoherent and lacks logic because no one can change the past. In other words, the idea of present times has no past or future, thus there should be no debate about a non-existent destination. However, if the only needed explanation is based on logical coherence, then it is easy to overcome these aspects. It is highly possible to build a coherent time travel situation, where everything takes place only once and in a coherent manner. But, Arntzenius and Maudlin (191) argue that logical coherence is quite a poor condition to depend on, based on the point of view of physics. Physically speaking, time travel is very much possible, as long as the problem of metaphysics is solved.
Stability of the traversable wormhole
One of the most prominent features of a stable wormhole solution is that it can aid the generation of closed time-like curves (CTCs). Such an approach can generate controversy, which can cause worries as to whether traversable wormholes can be realistically created (Bertolami, Orfeu, and Ferreira 29). Arguably, the exotic behaviors of traversable wormhole may arise from the gravitational back-reaction and other factors. However, the fact that these effects most often lead to instabilities that may prevent wormhole and CTCs, they may lead to impossibility of time travel (Bertolami, Orfeu, and Ferreira 30). From such analysis, wormhole and CTCs can be obtained under conditions, within the context of the non-minimal curve. To construct time machine, there are three steps that are indispensable: a stable traversable wormhole, a time shift between the two mouths, and a pull to bring them closer together in an adiabatic manner. The steps used to induce a time-shift suggests that there are some additional conditions on the form of acceleration applied to the wormhole entrance that keeps it traversable, as well as, stable (Bertolami, Orfeu, and Ferreira 30). However, the subtle point in this concept is that no additional constraints have been spotted in the whole process. It means that a stable traversable wormhole can yield CTCs. In short, the theoretical approach shows that non-minimal coupling that takes place between matter and curvature means that stable configurations can allow for time travel to obtain even ordinary matter.
Science fiction has over the years predicted possibilities that have come to pass. Today, science fictions are filled with scripts narrating and displaying traveling through wormholes tales. Some have branded these just fictions, yet some related scientific experiments have proven that it is possible to pass through the magic wormhole as one traverse the universe. Wormhole theory proposes that it is possible to pass through space-time faster across the universe. The prediction of a wormhole is based on the theory of general relativity by Einstein. As with every scientific prediction, many have doubted the possibility of passing through wormholes because of a number of reasons. For example, some have argued that it can experience sudden collapse, possess high radiation and contains some exotic matters that are quite dangerous. The reality is that wormhole may not only connect two separate sections of the universe but could also connect two different universes. Some scientists have also conjectured that it is possible to achieve time travel if one mouth or entrance of a wormhole is shifted in a specific manner.