I was watching the most recent episode of The Daily Show with Jon Stewart, which I had recorded on my iQ, when probably the coolest astrophysicist, Neil deGrasse Tyson, came on as the guest. I mean come on, the guy looks like he's straight out of a Fresh Prince of Bel Air episode! He just makes science sound so gangsta! Check out the video below as he takes a swipe at religious fundamentalists and even classroom teachers...
Anyway, I remember seeing him on the Daily Show a couple of years ago and he was talking about black holes and such, which then reminded me of the TV series LOST. Ok, for those of you who never watched the show might not understand the link but all you need to know is that in season 2, they find an underground bunker which holds a great deal of electromagnetic properties where numbers must be entered into a computer to discharge the build up of the electromagnetism, in order to save the world. It seemed that during the show's lifespan, the tv viewing audience were always split into three groups. The first group, followed it religiously, the second had never seen a single episode, and the third watched maybe the first season but then got confused and disillusioned when the show's writers began introducing themes such as 'smoke monsters' and time travel. For me, this was one of the show's greatest hooks. Instead of getting annoyed and frustrated by the new themes set out to confuse the audience, I began doing some of my own research into the topics, one of them being time travel.
So how can you travel through time without building a time machine? I mean, H.G. Wells' "The Time Machine" had a time machine and Back to the Future had the DeLorean, the time travelling car...
But how can you create a naturally occurring time machine? With a black hole (or wormhole) of course!
Now, I'm not an astrophysicist nor am I cool, black guy, but I will try to make as much sense of this as possible...
So let's start from the very beginning. Albert Einstein theorised that every object in space-time had an effect on the structure of space-time due to gravity. And the greater the mass of the object, the greater the effect. In astrophysics, the sun warps space-time more than the Earth. The pictures below give a basic example of this theory. Imagine space-time like a 2D piece of paper. Now let's say that if we were to put a weight on this piece paper, there would be a slight sinking effect towards the centre of the object. In the second picture, Earth is pulling and warping the fabric of space-time down due to its gravitational pull. Now let's replace the Earth with the Sun, which has 28 times the gravitational pull than that of Earth and imagine what would then happen to the piece of paper.
So what if we were to replace the Sun with an even larger star with much more mass and an infinite gravitational pull so huge that it ripped a hole through this piece of paper?
This is our black hole. When a star dies and implodes, as the nuclear reaction is finally exhausted and no longer strong enough to prevent the star's gravitational forces from collapsing in on itself, the star will dramatically change size and colour. The Sun, currently a Yellow Dwarf, will grow in size to a Red Giant, before imploding and turning into a White Dwarf.
So stars larger than the Sun will have greater gravitational forces acting upon it, which in turn can either turn the star into a neutron star or a black hole, where the gravitational force is infinite. That means that light itself, the fastest known 'object' cannot even escape it. The star is now a singularity at the centre of the black hole, surrounded by the event horizon, which gives the black hole its appearance.
But of course, how do you turn this black hole into a time machine? First you must make the black hole into a wormhole and how do you do that? By creating a second black hole at another point in space-time. Going back to the piece of paper analogy, what if we were to bend the piece of paper over so that the heavy object that has ripped through the top now rips through the bottom? This, in theory, is a wormhole.
But of course, how do you turn this black hole into a time machine? First you must make the black hole into a wormhole and how do you do that? By creating a second black hole at another point in space-time. Going back to the piece of paper analogy, what if we were to bend the piece of paper over so that the heavy object that has ripped through the top now rips through the bottom? This, in theory, is a wormhole.
Now I know what you're thinking...that looks exactly like that Simpson's episode that they did in 3D!
When black holes were first theorised, they were only thought of in a stationary state. But as we know, most stars rotate, so that when a rotating star becomes a black hole, the black hole would also be rotating. This would then create what is known as an 'ergosphere' external to the event horizon, where anyone inside this area would experience 'frame-dragging' of space-time. Of course if you were to enter a stationary black hole (or wormhole), you would not survive as you reach the centre of the singularity, as the gravitational forces begin shredding you down into your molecular structure. With a rotating black hole, the singularity would also be rotating, creating a ring, which theoretically when passed through, could take you to another point in space-time.
The only problem with the wormhole now is that if you were to pass through the singularity, even at the speed of light, you would be crushed instantly. In order to hold the throat of the wormhole open, you must have enough 'negatively charged' energy (or 'exotic matter') to keep the wormhole open long enough to pass through. Such 'exotic matter' was thought to not exist until Hendrik Casimir and Dirk Polder discovered that two uncharged metallic plates in a vacuum produced negatively charged matter. This is known as the Casimir Effect.
Ok, so now that we have created a stable wormhole and are able to pass through it, how do we use it to travel through time? First we go back to Einstein again. He theorised that a clock in motion would move slower in time than a stationary one and the faster a clock travels, the slower it will tick.
Now here's the cool part. So, theoretically, if someone were to travel 99% the speed of light in one direction for 5 years and then turned around and travelled back to their starting point, travelling again at 99% the speed of light for a further 5 years, they would arrive home in 10 years but would find that time on Earth has progressed 40 years, and so the traveller has travelled to the FUTURE!
So let's say that we were able to make a wormhole the size of a TV and throw it onto a spaceship. This is what physicist Kip Thorne theorised would happen. Kip stays at home with one mouth of the wormhole and his wife Carolee, gets into a spaceship and travels for 6 hours, then turns around and returns home in another 6 hours, totalling a 12 hour journey. During this trip, they hold hands. After 12 hours have passed for Kip, he looks into the wormhole and sees his wife landing outside in the front yard. So he lets go of his wife’s hand, gets up and goes outside but his wife and the spaceship are not there! So he waits…for 10 years!
When she finally arrives, he goes outside to greet her. He opens the door of the spaceship and finds his wife not having aged more than 12 hours since her departure, with her hand still in the wormhole. He looks into the wormhole and sees himself 10 years ago holding hands with Carolee. The wormhole is now a time machine! Kip can step through the wormhole and go back as far as 10 years, to the creation of the time machine but no earlier. The Kip on the other end can also step through the wormhole and come forward 10 years!
So the real question is...what are they really doing with that Large Hadron Collider?
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