Time is a measurement used to determine the progress of events, including the past, present, and future, according to physics. It is both a concept and a dimension, defined by physicists, to be non-tangible but is also a part of our reality. Although our understanding of time seems to be linear, the theoretical physicist Albert Einstein determined that time is relative.
Einstein's theory of relativity indicates that time is different depending on the location and speed of an individual or object, relative to the observer. In addition, it can also be influenced by gravity, resulting in time dilation. Other physicists inspired by Einstein's special theory of relativity and the general theory of relativity postulate that, theoretically, people can age at a different pace, especially if one travels near the speed of light or is near a black hole.
For decades, both scientists and laymen enthusiasts have often wondered if time is just an objective reality or a fundamental part of our universe. The subject also captured the imagination of many, including the thought of time travel. However, physicists assert that time travel into the past is impossible while going into the future is possible.
Interstellar Movie
In the 2014 film "Interstellar," the theory that time is relative was portrayed when a group of two astronomers and an engineer landed on a distant planet located in a different galaxy via a wormhole in our Solar System. The team seemed to have spent several hours on the alien planet to find a scientist that arrived before them.
Upon returning to their spaceship due to an emergency, one of their crew members left behind their spacecraft drastically aged while waiting for them, only for the group to find out that 23 years have already passed.
The movie explains that the passage of time in the said planet is extremely slow since it is near a black hole, with a strong pulling gravity. Meanwhile, the time on Earth moved faster because of relativity, with its inhabitants aged for 23 years, while the space expedition group who landed on the planet remained young.
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Time is Relative
In 1905, Einstein published his Special Theory of Relativity, which pertains to the relation of time with light and energy. Meanwhile in 1915, the renowned physicist's General Theory of Relativity was published and talks about another force in the universe that affects time: gravity, according to the American Museum of National History.
The combined theories, in the context of people aging at a different pace, apply to all observers and those undergoing acceleration. Yet, reaching such a feat is impossible, at least for now. This high improbability is evident as physicists have asserted that humans have no means traveling at the speed of light, which is 186,000 miles per second, according to NASA.
One of the major factors that prohibit our crafts from reaching light speed, or at least near it, is due to the presence of mass and other decelerating factors that lack of an infinite amount of energy.
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