Relativity

This entry is a tangent to my last entry but I promise it won't be as mind boggling.

The main point I want to make here is that the concept of time is man-made. I ask you; do you know why there are 24 hours in a day? Why is one hour the length of time that it is, why don't we call 45 minutes as one hour? Who chose the units of measurements that we use to calculate time?

The human race is very much dependent on calculating time. We pretty much run our lives around the time on our clocks. We are the only species on this planet that can understand the concept of time and assign an individual unit to a period of time that has passed.

The reason we have 24 hours in a day has nothing to do with any scientific based method of dividing a day. Ancient Egyptian astronomers observed that there were 36 decan stars throughout the year. A decan is essentially a subdivision of an astrological sign, such as the Zodiac signs, with each sign having three divisions of 10 degrees. An interesting side note here; this is also why there is 360 degrees in a full circle (36 x 10 = 360). Later, a more simplified system was created, where there were only 24 decan stars used for calculating time, 12 observed during the night, the other 12 assigned during the day. Hence, why there is 24 hours in a day. This is also the reason why a year is divided into 12 months, there being 12 lunar cycles in a year. It was then later calculated there being 60 minutes within the hour and 60 seconds within each minute, or 3,600 seconds in each hour, again relating back to the 36 decan stars.

So, even if hours, minutes and seconds are all man-made inventions, created in order to run our lives more efficiently, what about days and nights and years? One revolution of the Earth on its axis creating one day or one Earth's orbit around the Sun creating one year. Not man-made at all. But then again, one could argue that one day or one year on any other planet would not be the same as Earth and that this measurement of time is all relative to us humans here on Earth.

Take Mars for example; each day lasts for approximately 24 hours and 40 minutes while a year lasts approximately 687 days. If we were living on Mars instead of Earth, our idea of how long a day/year lasts would be slightly different, and more so if living on, say, Mercury where one Mercury day lasts 176 Earth days and one Mercury year lasting 88 Earth days.

This is one particular thing that annoys me when watching most science fiction films or television shows. When humans are interacting with an alien species, they very casually talk about days or hours and these aliens know exactly what us humans are talking about. How? The alien species would have a completely different concept of how long an hour or day lasts. When we are talking about travelling faster than the speed of light, and through wormholes, this oversight could have huge devastating consequences to both ship and crew. Oh well, I guess it's just TV right?

That is not to say that all science fiction films do not take this into account. Take "Men In Black" for example; when the Arquillians threaten to destroy Earth if the galaxy is not returned to them and give Kay (Tommy Lee Jones) and Jay (Will Smith) one galactic standard week to return it, which turns out to be just one Earth hour.

Kay: Arquillian battle rules, kid: first we get an ultimatum, then a warning shot, then we have a galactic standard week to respond.

Jay: A galactic standard week? How the hell long is that?

Kay: One hour.

Jay: One hour...then what?

[the message translation flashes across the screen: "MIB, DELIVER THE GALAXY OR EARTH WILL BE DESTROYED"]

Jay: Oh, now that's bullshit!

Now I dig into Einstein's theory of relativity. As explained in my previous post, time is greatly affected by gravity, and the greater mass and gravity of an object, the more space-time will be affected. This essentially means, the CLOSER to a large body of mass you are, the SLOWER time will appear. This theory can even be proven here on Earth. If you had a pair of synchronised clocks and if someone was to hold one of those clocks on the surface of Earth and you were to take the other clock to the top of a skyscraper or on to an airplane, time will move quicker the higher up you go and the further you move away from Earth's gravitational pull.

This also means that the larger the mass and consequently the higher the gravitational pull, the slower time will appear to run. Taking the two clocks analogy again and keeping one on Earth and taking the other to Jupiter, the clock on Jupiter will tick slower than the clock on Earth. In fact, it is theorised that the person holding the clock on Jupiter will age slower than the person on Earth. I think I've just discovered the new anti-aging fad!

What makes this theory cool, or at least it does for me, is that if you have an object with an infinite gravitational pull, such as a black hole. One theory is that; the person holding the clock on Earth looking at someone holding the other clock entering a black hole, will appear to slow down as they enter the event horizon and if it were possible to see that person continue to fall into the black hole past the event horizon, then they would appear to almost freeze in time. AND for the person holding the clock, falling into the black hole and looking back out at the rest of the universe, because time is slowing down for them, it would appear that the time for the universe in SPEEDING UP! This would theoretically mean that the person falling into the black hole could witness the complete life cycle of the universe and its ultimate end within a few seconds!

Time is all relative.

Time Travel

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...

http://www.youtube.com/watch?v=zEP50dxfRAw

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.

Now I know what you're thinking...that looks exactly like that Simpson's episode that they did in 3D!

Sort of similar, but where Homer Simpson travelled through space, we want a wormhole that will allow us to travel through time.

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?

Perception

I just finished watching 'Inception' and that got me thinking...

How do you see the world? Is it the same way in which your mother or father see the world? Of course your parents will use past experiences to see the world in a different light, but I'm talking about physically seeing the world. In essence, what is reality?

No, I'm not talking about the Matrix. Although to a certain extent, the Matrix trilogy (or at least the first film), made the audience question their own reality. If I can see it and I can touch it, it must be real, right? But why must it be real, just because your brain is using sensory inputs such as sight, sound and touch, to create a picture of the world around you. As Morpheus says to Neo; "Your mind makes it real".

A perfect example is visual perception. When light enters the eye, the image that the retina picks up is up-side-down. But of course this is not what we see. Our brains use this information to flip the image back around to its correct position. So our brains are taking this sensory input and changing what we actually see.

So what part of our brains is responsible for interpreting all of this information? The Central Nervous System (CNS) is where all the information from the peripheral nervous system is received and processed. It is also responsible for controlling body movement and all biological processes through electrical signals.

Now, I'm not biochemistry major, but I'm going to try and explain this as easily as possible. Without going into too much detail, the nerve cells in the CNS have receptors, "protein molecules", that interact with other produced molecules within the CNS, such as other protein, neurotransmitters and hormone molecules, which can attach themselves to these receptors, causing specific biological activity in the human body.

Still with me? One particular neurotransmitter molecule that is produced in the brain, as well as the stomach, is 'serotonin'. Now this biochemical is responsible for regulation of mood, appetite and sleep.

Of course, this is all natural biochemistry at work here. So what if, in one particular individual, the brain began producing an unknown chemical that attached and interacted with these receptors, causing information received by the CNS from the sensory inputs to be interpreted differently? Would this individual then begin to perceive the world differently, sound, touch, taste, sight, all because their brain began processing information differently?

This new 'unknown' chemical may be either activating this receptor (agonist) or blocking it (antagonist), altering the information it receives. Now, let's say this unknown chemical being produced, although physically and biochemically impossible, was lysergic acid diethylamide (or LSD for short) or at least something that produced the same affect on these receptors, by disrupting the interaction between the nerve cell and neurotransmitter, which specifically targets serotonin neurotransmitters.

Ok, I know what you're saying now. "But LSD is a man made, synthetic drug! Your brain can't just start producing acid and tripping out!" But the only point I'm trying to get across is; what is perception? What is reality? For someone who could produce LSD or other hallucinogens internally, which would in turn alter their perception of reality, would that not also be a certain, albeit different, reality? When your brain naturally increases its serotonin levels, which in turn makes you feel happier, is this not also altering your perception of reality to a certain degree. What if, in an alternative universe, all humans had evolved with such an 'ability', this state of mind would be the accepted common reality.

All I'm saying is that your perception of reality is what your mind makes of it.

Neo: I thought it wasn't real

Morpheus: Your mind makes it real

Neo: If you're killed in the matrix, you die here?

Morpheus: The body cannot live without the mind

Metacognition

I have never written a blog before and I thought it was about time I used some of my down-time to start writing again. So here goes nothing...

I've named my blog "Deep Thought" for more reasons than one. Ironically, it didn't take too long to come up with the title. It seemed pretty obvious that people use blogs to write their own thoughts and feelings about certain events in their lives, so that is reason number one. This is somewhere where I can freely write whatever is on my mind. Reason number two; for those of you who are familiar with Douglas Adams' "The Hitchhiker's Guide to the Galaxy", you will know that 'Deep Thought' is the super computer created to answer the question to 'the Ultimate Question of Life, the Universe and Everything'.

This then brings me to the title of my first post: Metacognition. I first heard the word back in highschool when my Psychology teacher, who also happened to be my English teacher, began talking about the concept. He summed it up by saying that metacognition was 'thinking about thinking'. At first I didn't quite understand what he was talking about but then that got me thinking more about it, which of course lead me to understand, as this very thought process was metacognition.

He then went to go on about how metacognition is what separates us humans from the animals, that our sapient brains have evolved over time in order for us to understand abstract concepts and be self-aware. So is metacognition something that defines intelligent life?

Probably not but it would be one of the criteria. Studies have shown that primates have metacognitive abilities while other animals such as birds do not. What is surprising is that recent studies have also shown that lab rats may be showing signs of metacognition. To cut a long experiment short, basically the rats were given a listening test. The rats were to determine whether the sound they heard was "long" or "short". If they answered correctly, they were rewarded with food. For an incorrect answer, they received nothing. However, they were also given the option to not answer at all, and receive a small portion of food. So in theory, the rats were able to think about their own thought processes and make judgements about their decisions.

Where there was an obvious and easy answer, such as a very short or very long sound, the rats had no problem answering the question and receiving their reward but with mid-ranged sounds, more often than not, the rats chose not to answer as they knew they didn't know the answer to begin with, deciding that a small portion of food was better than the chance of them getting the answer wrong and receiving nothing.

Again, all those Hitchhiker's fans out there would recognise the link here. Those responsible for the creation of Deep Thought were beings from another dimension, which in our dimension were seen as white mice.

So in the greater scheme of things, what does this mean? Does my dog understand his own thoughts and why he makes the decisions he does or does he just do those things out of instinct? Are we the only life form on this planet which is self-aware? Or is metacognition a dormant characteristic that can only be achieved upon reaching a certain level of evolution?