14 March 2006

On the Matter of Redshift and Blueshift

I explained in my previous post that my favourite colour changed from green to black (ultraviolet) because of blueshift. The blueshift is a result of my past moving away from me.

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For those of you who realised, no, that's not a mistake, it's deliberate... to see how attentive the readers are.

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If you don't know what I'm talking about, and if you know some things about physics (particularly on Doppler shift), then shame on you! Because when a source is moving away from a detector, the waves will undergo redshift instead of blueshift. Only if they're moving towards each other will it be blueshift.

Sigh...

Anyway, a little elaboration to the eye seeing ultraviolet part... yes, our eyes have light cones (some cells in our retina) that allow us to see a range of colours, going from red to a little bit of ultraviolet. But because of some layer in our eyeball, it blocks out the ultraviolet, so our eyes can only detect what we now know as the visible spectrum.

Interestingly, I heard of a person who underwent an eye operation that resulted in his UV-absorbing layer being removed. So he effectively can see ultraviolet. Too bad I could not find out how ultraviolet "looks" like.

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