Tuesday, 26 January 2016

Is it a colourless world?

The theories of reflection suggest that the colours we see depend on the amount of white light it absorbs and the amount it reflects. White light is colourless light like ordinary daylight, ie, it is the light humans see when all the colours (VIBGYOR) make up visible light. The different colours which comprise white light have different wavelenghts. Light always travels in waves and wavelength is nothing but the distance between the crests of two waves. Scientists say that when white light falls on any object or surface, some of the wavelenghts get absorbed while others get reflected. We see the portion of the light which is reflected and that is how we perceive the colour of a thing. When all the colours are absorbed a thing appears black and if none of it is absorbed, an object appears white. For example, when white light falls on an apple, all the colours of VIBGYOR gets absorbed excepting red. The red light is thus reflected and that is why when we look at an apple it appears to be red. Similarly, a sunflower is yellow because it absorbs all colours other than yellow, a rose is red, a chocolate is brown and parrots are green.
So if every colour we see is a result of refection of white light falling on it, what is the actual colour of a thing, rather, does colour even exist? If white light was not there, would roses be blue, or green, or would they be colourless? The colours make everything looks beautiful, be it a garden or a temple or a bride. But, do all these things even have a colour of their own? What if white light is no longer available one day: would the world be colourless? Even if it were colourless, what does colourless actually look like? I wonder....

5 comments:

  1. Do you know about the secret messages that flowers send to bees?
    About your question as to whether things have a colour of their own: I think in the absence of light, the idea of colour itself is meaningless. Similarly, in a hypothetical world where there were no airborne molecules, it wouldn't make sense to ask whether roses smell sweet, because the idea of smell itself would be meaningless.

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  2. Also, speaking of colour, this is one of my favourite optical illusions.

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  3. No what I meant was not the absence of light as in complete darkness or no vision. What I meant but could not frame properly was that if for instance the colours that we see were not a result of reflection of light, would they inherently be colourless. The question that comes to my mind is, what do things actually look like.
    As for the secret messages, yes, you showed it to me when you came over. The optical illusion id fantastic. Almost unbelievable.

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