Why do we shiver..?

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One thing about the rains... they are awesome.. the greenery looks amazing with new sprouted leaves. We went for tea, walking all the way in rain, jumping the flowing water. It's cold and i started shivering. And I started thinking about it..

We can decrease the heat loss from our body by bringing our hands and legs close by reducing the surface area. But beyond that..? that's where shivering could help. I think shivering is like minuscule exercise. This generates some heat inside the body. 

Why are we not comfortable with White Led "street lights" or some yellowish tubelights??

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I don't know about others but I am uncomfortable with this and I tried to find what could be the reason for this. Possibly the problem could be different for others and the reasons could be different. These all depend upon the exposure of us and our earlier generation. However, wondering about things is the main motivation behind this blog.

So the thought is: Over the generations we got used to sunlight (spectrum). As we know white light is a mixture of various colors. 

Now if we look at Tubelight specifications: a temperature is mentioned. Now from Planck's theory on Black body radiation, if the spectrum is same as that of sun's light, we feel the light as comfortable because it has that similar amount of colors mixing to produce white light as in sun light. 

Because over the years our sensors (eye's cones & rods) got calibrated well to this detection level (of that spectrum range). If the temperature mentioned is different, you will technically see some color of light more dominating. 

Now if we look at LED street lights, the phenomenon is that we pass current and electrons get recombined to give flash of light (at a frequency we can't distinguish between continuous or discrete). So the light has some particular wavelength (may be green/blue/something..) but not white because we can get white only through the combination of different colors. So they have small LEDs packed together which give red, green, blue on whose combination white light is seen. You can learn a bit more on LEDs in this link: white light using LED

The problem with this is that the resultant spectrum is "whether it is same as that of the sun light ?" So as long as the resultant spectrum is same as sun light spectrum (for people who are more habituated to day light), the eyes feel comfortable.

Any suggestions to improve the article are welcome..!