LIght StrIkIng Matter
3. LIght StrIkIng Matter
Light coming from the sun reaches the earth at a speed of 300,000 km per second. Owing to the speed of light, we always see a world full of colour. How, then, is this uninterrupted image made?
Passing through the atmosphere at enormous speed, light reaches the earth and strikes objects. When light strikes an object at this speed, it interacts with the atoms of the object and reflects at different wavelengths corresponding to different colours. In this way, the book you are now holding, its lines, pictures, the view you see when you look outside, trees, buildings, cars, the sky, birds, cats, in short everything your eyes see, reflect their colours.
The molecules enabling these colours to be reflected are pigment molecules. That is, the colour reflected by an object depends on the pigment molecules present in that object. Every pigment molecule has different atomic structures. The atomic numbers as well as the types and the sequences of atoms in these molecules are different. Light hitting such diverse pigments is reflected in different shades of colour. However, this is not enough for the formation of colour. For reflected light possessing a certain colour quality to be perceived and seen, it has to reach a visual apparatus capable of perceiving it.
 The rays coming from the sun consist of particles called "photons", which move in waves. When photons hit the electrons of the atoms making up physical objects on earth, the electrons emit light rays of particular wavelengths, which "correspond to certain colours". When sunlight falls on a leaf, for example, this means that the photons of light have hit the atoms of the pigment molecules existing on the surface of the leaf. On impact, the electrons of the leaf's atoms are activated. As a reaction, the atoms of the leaf emit photons. Thus, the photons representing "the colour" of the leaf begin to travel towards our eyes. |
4. LIght ComIng to the Eye
For rays reflected by objects to be perceived as colour, it is necessary for them to reach the eye. The existence of the eye alone is not sufficient. After reaching the eye, the rays ought to be converted into nerve signals that reach a brain working in harmony with the eyes.
Let us think about our own eyes and brains as the closest example. The human eye is a very complex structure that consists of many different organelles and parts. As a result of the simultaneous and harmonious operation of all these parts, we see and perceive colours. The eye, with its tissues and organelles such as lachrymal glands, cornea, conjunctiva, iris and pupil, lens, retina, choroid, eye muscles and lids, is a matchless system. In addition, with its extraordinary nerve web that establishes its connection to the brain, and extremely complex vision area, the eye, as a whole, has a very special structure, the existence of which cannot be attributed to coincidence.
After a short introduction to the eye, let us also look at how the event of seeing takes place. Light rays coming to the eye first pass through the cornea, then the pupil and lens, and finally reach the retina.
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The perception of colour begins at the cone cells in the retina.
There
are three main cone cell groups that strongly react to certain
colours
of light. These are classified as blue, green and red cone
cells. The
colours red, blue and green, to which cone cells react, are the
three
primary colours existing in nature. With the stimulation of cone
cells,
which are sensitive to these three colours, at different
degrees, millions
of different colours appear.
The cone cells convert this information
pertaining
to colour into nerve impulses through the pigments they contain.
Next,
nerve cells connected to these cone cells transmit these nerve
impulses
to a specific area in the brain. The place where the
multi-coloured world
that we view throughout our lives is formed is this area in the
brain
measuring a few centimetre squares.8
| Everything we see in the outside world is perceived in the brain. Colourful flowers, birds, the sky, mountains, the people around us, in short, every single detail in the world is projected to us inside our brain. In fact, the brain is an entirely dark place. He Who enables us, in this dark place, to see, to feel, to touch, to hear, that is, to perceive all the details of the outside world, in short, makes us watch everything, is Allah, Who has created the whole universe. Allah has power over all things. |  |
5. A Colourful World In Our Dark BraIn
The final stage in the formation of colour takes place in the brain. As mentioned in the previous chapter, nerve cells in the eye convey the images converted into nerve impulses to the brain and everything we see in the outer world is perceived in the vision centre of the brain. At this point, we are confronted with an amazing fact: the brain is a piece of meat that is completely dark inside. Nerve impulses coming from images created on the retina by objects are deciphered in the brain, which is completely dark inside. Images of the objects, with their colours and all other properties, are formed as perceptions in this visual centre. How does this process of perception take place in such a piece of soft meat?
A lot of question marks remain as to how colours are perceived. Chromatists are still unable to answer those questions such as how nerve impulses are transmitted to the brain via optic nerves and what kind of physiological effects this creates in the brain.9 All they know is that the perception of colours as realities takes place within us, that is, in the centre of vision in our brain.10
In fact, most of the processes carried out by the brain have not yet been elucidated. The explanations of the subject are largely based on theories. However, the brain has been fulfilling all its functions perfectly since the moment man came into existence, just as it does today. People's experiencing a three dimensional world, along with all its colours, designs, sounds, smells and tastes, in a piece of meat weighing nearly one kilogram is made possible only by the perfect creation of Allah. Everyone finds this matchless miracle of creation ready at birth. Man has no control whatsoever, neither in the formation of its functions, nor in their continuity, nor at any other stage.
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8. Bilim ve Teknik Dergisi (Journal of Science and
Technics), No: 366, p.81
9. Bilim ve Teknik Dergisi (Journal of
Science and
Technics), October 1986, p.6
10. Bilim Teknik Dergisi (Journal of
Science and
Technics), October 1986, s.6-9
