Sunday, March 12, 2006

The small things of science

People that don't wok much with science think usually that big things are important. Sending probes to space, decoding the DNA, building bigget and better satellites... But I think that every scientist that truly loves what he or she is doing, he does it for the small things. The small things of science that may seem insignificant, but for some reason they offer the greatest joy and they make us to want to continue doing it. We all do research, struggle to go through the phd, come up with better ideas...but at the end I think the small, everyday things - the journey itself - is what is more sweet rather than the final grand destination.

I still remember how happy I was when I discovered that Brewster's angle does not hold for lossy materials. This is an angle at which if you look a reflection (through polarized sun glasses), the reflection goes away. Disappears. Completely. Really! (It can't be a mirror reflection though; it has to be an ordinary material like glass or air - I did the test myself watching the reflection of my window on a plate full of water). But then, in a class a couple of year ago, I had ot derive the same thing for a lossy material. And as it turned out, if the material has some loss, then this angle doesn't exist! You always have some reflection. I just found it amazing how a perfect material can cause the light not to reflect (all the light goes inside the material), but a lossy one cannot...

I experience another small thing of science today. Sure, we do this big complicated experiment, where we try to excite an electric field in the plasma and accelerate particles to the speed of light. But then, there are all these small things that spice up thw whole experience. The light from the plasma travels through an optical fiber to a spectrometer which analyzes it to its colors. I measured these colors (spectrum) while varying the entrance slit of the spectrometer that the light goes through; and while you would expect the width of the picture to grow linearly, and keep its square shape (because of the squareness of the slit), gradually it started deviating off from the line... it became more and more curved, approaching the circle as I increased the slit size... And only later did I realize that what I was really looking at was the optical fiber itself! Without me realizing it, I had increased the slit to the size of the optical fiber (400μm - 15m long)... so obviusly the image couldn't be square anymore, it was limited from the fiber... and instead of the light increasing proportionally, it short of became flat after a while... It was as clear as a mathematical proof from Erdos' Book...

What small things of science have you discovered recently?