Time Travel and the Universe

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Some people claim that travel in time is just not possible and other claims that the time machine is the ultimate way to travel back and forth in time.
A time machine would be possible, since the earth, planets and universe itself is one big power machine.
Wouldn’t it be great if we could go back to the past and see ourselves as a child or go back to see the World War 1, or perhaps travel to see our future selves?

Time and the speed of light

If we where asked to define time we often look at the watch to see what time it is, or simply say “time just is”.

Time as a dimension

The universe includes at least four dimensions.
Longitude, latitude and depth are the ones sometimes called “the three room dimensions”
Unlike the three room dimensions the fourth one is not symmetric and only has one direction, and that is time.

Speed of light

What really is the speed of light?
Speed of light is really fast, which is 299 792 458 m/s.
It is impossible for us to travel at the speed of light, we could travel 99.9% near the speed of light, but never ever gain that small 0,1%, since the speed of light is the ultimate speed that exists.
It’s as basic as gravity. And strange things happen when travelling near the speed of light.

If an object travelling near the speed of light, it compresses the lightwaves and the object appears to be blue when approaching.
When leaving the lightwaves stretches out behind and the object becomes red since short lightwaves are blue and long are red.
A person who travels near the speed of light sees everything squeezed like a kind of tunnel which appears to be blue in the center and red at the edges.
A more bizarre thing that happens near the speed of light is that time slows down for the traveller and the traveller age more slowly than the rest of us.
So how is this possible?
Imagine a lightclock; with two mirrors facing each others, and a light particle bouncing between them, each bounce is one tick of the clock.
When you move the clock back and forth the lightparticle makes a zigzag motion and takes longer time to reach one mirror to the other so the clocktics is slowing down.
But if you’re travelling near speed of light you’re not aware of the change, because everything happens onboard. Including your heartbeat and brainwaves will slow down by the same amount. The faster you travel the further the lightparticle have to travel between tics and the slower time passes for the traveller. So one hour for the traveller could be hundreds of years for the rest of us, so he will travel hundred years into the future.


Black Holes

A black hole is what remains when a star collapse.
So what is a star, and why does it die?
Stars are gigantic glowing balls of hot gases of mostly hydrogen and helium.
Not all the stars are the same, they come in different sizes, colours, brightness and temperatures.
It is stars that are more massive than the sun that create black holes.
When the core runs out of its fuel the star starts to transform all its helium into carbon.
After all helium is transformed, the mass is enough to transform the carbon into heavier elements such as iron. When the core has turned into iron it cannot longer burn.
The star collapses by its on gravity and the iron core heats up.
The core becomes so strongly packed that all the protons and electrons combine to form neutrons. In less than a second the core shrinks to a neutron core with a radius of 10 kilometers. The core heats up to billions of degrees and a Supernova explosion occurs.
The great amount of energy and material that are released during the explosion is surrounding the explosion itself and is so strong that not even light cannot escape. What is left in the center is a big black hole surrounding with rotating energy and sucks in everything that comes close to the fallen core.

So what will happen when a person would be sucked into a black hole?
On the opposite side of the black hole there is a white hole, which have exact opposite effect than the black. Instead of pulling in objects the white hole is pulling out and away objects.
Some scientists believe that it would be possible for us to travel into this black hole and maybe travel through time or other worlds.
According to mathematician Roy Kerr’s theory rotating black holes do not have a singularity (geometrical point in the center), since a dying star would collapse into a rotating ring of neutrons that would produce great amount of centrifugal energy to stop the creation of a singularity, and therefore is safe to enter without being crushed by the gravitational force.
Other scientists claim that the laws of physics prevent such a creation, and any attempt to enter a black hole will be destroyed before it even reaches the center.
But there is little we know about black holes and this is of course only speculations.

Click on the link below for Black Hole picture

http://i34.photobucket.com/albums/d101/SuccubusGirl/BlackHole.jpg

Wormholes

The whole idea of wormholes is actually pretty mysterious.
Einstein once came up with the idea that mass bends space and the bigger the mass is the more space will be bent.
Think of it as two people holding two sheets stretched out over each others, which are representing two different universes. A ball is put near the edge on the first sheet. Automatically the ball is rolling towards the center; the weight of the ball makes the sheet bending downwards. On the opposite side of the other sheet they do the same. Also this ball is rolling towards the center. And the two sheets is bending towards each other and creating a tunnel.
Masses that lay pressure in different part in space could eventually bump into one another and form a tunnel, and this tunnel is a wormhole.
Wormholes will not only allow us to take massive shortcuts to for example other planets or galaxies, it will also allow us to travel into the past as well as into the future.
And how is this possible?

Imagine 2 people, we name them Person A and Person B.
Person A stays on earth while Person B travels into space with 50 percent of the speed of light.
So let’s say the entrance of the wormhole is moveable.
Then Person B travels into space for a few hours and carry one wormhole entrance with him, while the other entrance at the opposite side stays with person A on earth.
As Person B travels into space the two people would continue to see one another.
Since time slows down for Person B, years could have passed on for Person A, when B returns a few hours later.
Now, as the older person A looks through the wormhole that travelled into space, he will see himself at the age when person B launched into space and would also be able to enter the wormhole while the younger person B could step into the future

See link below for wormhole picture

http://i34.photobucket.com/albums/d101/SuccubusGirl/Wormhole.jpg


Paradoxes

If we would manage to travel back and forth in time it would probably leads to loads of complications. This complication is called paradox.

The most recognized paradox is the grandfather paradox.
If you would travel back in time and kill one of your parents or ancestors before you even were born, what would really happen?
If you killed for example your grandfather, then how could you be alive and travel back in time to kill your grandfather?
If we really could chance our past it would cause countless number of paradoxes.

Ideas of parallel universes or alternative histories have also been brought up.
Let’s imagine you really did go back in time and kill your own grandfather when he was a young boy.
The whole theory of parallel universes is that you may have travelled into another universe similar to ours, but with different sequences of events.
So you’ve only killed that person in one universe, which is no longer the universe you really exist in. The real complication with parallel universes is that you never will be able to return to the universe you started in; instead you will travel into another parallel universe when you try to travel back to your real universe.
The theory ...