Time Travel Science Fiction or Reality?. Is It Possible? Whenever we think of science fiction, we think of outer space, black holes, other dimensions.

Time Travel

Science Fiction or Reality?

Is It Possible?

• Whenever we think of science fiction, we think of outer space, black holes, other dimensions and time travel. But is it proper to classify time travel as science fiction? Many people would say yes because they think it is not possible. As a matter of fact it isn’t possible to time travel yet. Scientists always look for a way to prove that something exists or it doesn’t. Time travel actually cannot be proved or debunked but we are beginning to see that time travel actually isn’t as imaginary as we thought it was.

Origins of the Concept of Time Travel

• There is no way of knowing what are the earliest concepts of time travel but there are many old stories about traveling forwards in time:

• 700’s BCE to 300’s CE –Mahabharatha King Revaita travels to heaven to meet the creator Brahama, but when he travels back to Earth, he finds out many years have passed.

• 720 CE- Urashima Taro – A young fisherman named Urashima Taro travels to an undersea palace for three days and finds out three hundred years have passed on the surface.

• 1819 Rip Van Winkle – A man named Rip Van Winkle takes a nap at the top of a mountain and wakes up twenty years in the future.

• 1771 – L’An 2440, reve s’il en fut jamais – The main character falls asleep and wakes up in Paris during the year 2440.

• 1838 – Missing One’s Coach: An Anachronism – A man takes a nap under a tree and wakes up one thousand years in the past.

• 1843 – A Christmas Carol – Ebenezer Scrooge is transported to the past, present and future by ghosts.

• 1861 – Paris avant les hommes – The main character is transported back thousands of years and meets dinosaurs and humankinds earliest ancestors.

• 1889 – A Connecticut Yankee in King Arthur’s Court- The main character is transported back in time to King Arthur’s palace after he was hit with a sledge hammer in a fight.

• 1895 – The Time Machine – This is the first story that uses the phrase time machine.

Time Travel in Theory

• There are theories that actually would allow us to travel in time if these geometries are possible. Physicist don’t talk about traveling thought time, they talk about moving through curves in space that bend time as well which would allow whatever travels through them to return to their own past. In reality, it is possible to travel forwards in time in space because time travels faster on earth than in space so if someone were to travel to Neptune for example, the trip would probably take 20 year but 30 years would have passed on Earth.

Tourism in Time

Stephen Hawking once said that the absence of tourists from the future constitutes an argument the existence of time travel. This doesn’t prove that time travel is impossible, just that it hasn’t been developed yet or never used. Hawking notes that time travel might only be possible in a region of space-time that is warped the right way that we cannot create until the future. There is also a theory that states that you can only travel back until the point the time machine you’re using was invented, which would explain why we haven’t run in into any travelers from the future.

Time Travel to the Past in Physics

• Time travel to the past is theoretically possible using the following methods:

• Space traveling faster than the speed of light• The use of cosmic strings and black holes• Wormholes and Alcubierre ‘warp' drive

Time Travel via Faster-Than-Light Travel

• If you could move information or matter faster than the speed of light, then according to special relativity, there would be an inertial frame of reference in which the signal or matter would be moving backwards in time. To accelerate an object to the speed of light, it would take an infinite amount of energy to accelerate an object to the speed of light.

Wormholes

• Wormholes are hypothetical warped spacetime permitted by Einstein’s field equation of general relativity, although it would be impossible to travel through a wormhole unless you knew it was a traversable wormhole.

• The way to travel in time is to accelerate one end to the speed of light and leave on end stationary. Anyone traveling through the stationary end to the spinning end would travel forwards in time and backwards in the other way.

Black Holes

• Black holes are the end result of suppermasive stars after they go supernova. When these stars are about to die, they implode into a single point, called a singularity and explode. The singularity is small at first but soon it turn into a giant hole in space which is known as a black hole. Many people believe that black holes are portals to other universes and worlds but some believe they may be time machines. Every one knows that nothing can escape a black hole, not even light. It is because of this law that many believe we can travel back in time. Some physicists believe that time is a dimension that intersects with ours. If light can’t escape from a black hole, then maybe time can’t either so going through a black hole or just residing near it’s event horizon would allow an object to travel back in time.

Alcubierre’s Warp Drive• In 1994, the Mexican physicist Miguel Alcubierre proposed a method of

stretching space in a wave which would in theory cause the fabric of space ahead of a spacecraft to contract and the space behind it to expand. The ship would ride this wave inside a region known as a warp bubble of flat space. Since the ship is not moving within this bubble, but carried along as the region itself moves, conventional relativistic effects such as time dilation do not apply in the way they would in the case of a ship moving at high velocity through flat spacetime. Also, this method of travel does not actually involve moving faster than light in a local sense, since a light beam within the bubble would still always move faster than the ship; it is only "faster than light" in the sense that, thanks to the contraction of the space in front of it, the ship could reach its destination faster than a light beam restricted to traveling outside the warp bubble. Thus, the Alcubierre drive does not contradict the conventional claim that relativity forbids a slower-than-light object to accelerate to faster-than-light speeds. However, there are no known methods to create such a warp bubble in a region that does not already contain one, or to leave the bubble once inside it, so the Alcubierre drive remains a hypothetical concept at this time.

Tipler Cylinders

• Tipler cylinders are a concept put forward one hundred and fifty years ago. The basic formula to make one is to get matter strong and flexible enough to stretch into infinity and then it must be spun. Clockwise for future and anti-clockwise for past. Then you get a spaceship to travel through it and if it makes it through, the ship will end up in a different time.

Time Travel to the Future

• There are more ways to travel to the future than to the past. Some of theses methods are

• Time Dilation Theory of Special Relativity

• Time Dilation Theory of General Relativity

Theory of Special Relativity

• Time dilation is permitted in both of Einstein's Theories of Relativity. The theories state that time passes slower for moving objects than those that are stationary. For example a clock that is moving will appear to go tick slower than a stationary one. As the clock approaches the speed of light, the clock will seem to stop. Using the twin paradox we can assume that if one twin travels to Alpha Centauri at the speed of light and one twin stays on Earth. For the traveling twin about 8 years would have gone by but maybe a thousand years would have gone by on Earth for the Earth twin.

Theory of General Relativity

• Another way to travel back in time is to reside within a hollow sphere with a great mass. Let’s say that this object has the mass of Jupiter. If you stay in it for one hour you would exit it and four hours would have gone by.

Time Perception

• Two other ways of that people travel through time at a faster pace are Hibernation and Suspended Animation. They are however not recognized as time travel because they would still go at normal pace instead of an accelerated way of travel.

Paradoxes• Paradox-something absurd or contradictory: a statement, proposition, or situation that

seems to be absurd or contradictory, b…

• - self-contradictory statement: a statement or proposition that contradicts itself

• - person of opposites: a person with seemingly self-contradictory qualities

• If we were to travel back in time, what would we do? How many laws of physics and nature would we break? What would happen if someone tried to go back in time to kill their grandfather before he married his grandmother? Is there a way of changing the past without endangering the future? These are some of the questions that physicist and everyday people ask themselves if we were to travel back in time. Paradoxes are what people fear in the world of physics and many wonder there a way around them”

Paradoxes (cont.)

• There are some theories that allow us to evade paradoxes. A theory says that anyone traveling through a wormhole can never engender paradoxes because they would only be allowed to travel through time but not be able to interact with it. Another way to evade paradoxes is through the theory of parallel universes that would allow a traveler to be transported to a universe that favors the outcome of his change. Another more somber theory states that the universe is conscious and will stop anyone who tries to change it by making them disappear on their way to travel through time. Finally, there is a theory that states that any changes to the time stream would disintegrate the universe itself.

Grandfather Paradox

• The most famous paradox when it comes to time travel goes like this. Tim hates his grandfather and would like nothing more than to kill him. The only problem for Tim is that his grandfather died years ago. Tim wants so badly to kill his grandfather himself that he constructs a time machine to travel back to 1955 when his grandfather was young and kill him then. Assuming that Tim can travel to a time when his grandfather is still alive, the question must then be raised; Can Tim kill his grandfather?

The Solution• Consider now the fact that Tim’s grandfather died in 1993 and not in

1955. This new fact about Tim’s situation reveals that him killing his grandfather is not compassable with the current set of facts. Tim cannot kill his grandfather because his grandfather died in 1993 and not when he was young. Thus, Lewis concludes, the statements "Tim doesn’t but can, because he has what it takes," and, "Tim doesn’t, and can’t, because it is logically impossible to change the past," are not contradictions, they are both true given the relevant set of facts. The usage of the word "can" is equivocal: he "can" and "can not" under different relevant facts. So what must happen to Tim as he takes aim? Lewis believes that his gun will jam, a bird will fly in the way, or Tim simply slips on a banana peel. Either way, there will be some logical force of the universe that will prevent Tim every time from killing his grandfather

So Should We Time Travel?

• Maybe we can travel in time but should we. Many theories out there state that even if we could go back in time, we couldn’t change it because time is prewritten, maybe by God or destiny or who knows so there might not be any point in time traveling. Right now we don’t have the technology to travel through time but one day we will and only then we can see what really will happen.

Claims of Time Travel

• Philadelphia Experiment• Chronovisor• Billy Meier• Darren Daulton• John Titor• Moberly-Jourdain Incident• Montauk Project• Time Slip

Religion And Time Travel

• Many people believe hat God exist but where would he exist if he doesn’t age? For him to exist he has to pass through time but the Bible says that he never ages but it is said that God can change time as well. God is believed to exist outside our dimension but can travel to ours if it wishes as well.