Question: Why are you so obseesed with lasers

Peta Foster answered on 14 Nov 2011:

I am obsessed by light, it fascinates me. I love the fact that there are so many colours and yet those are the same ‘stuff’ as the microwaves that cook food or radiowaves that my car picks up in the morning.
What is it?
When i first asked that question i was simply told electromagnetic radiation which felt like just a name more than an explanation. Then my teacher told me it was a wave and i still didn’t understand. Waves on water makes sense to me because i have the image of all the little molecules being bumped up and down.
So what is light? What is oscillating?
I was told it was an electric field and a magnetic field oscillating and so i thought… ok so an electron makes an electric field and a magnetic makes a magnetic fields but without the electric and magnetic field what is making the field stick around?

So this bugged me and i the more i thought about light the more questions i seemed to have.

Laser light is pretty special. It has a property called coherence which means all the ‘waves’ have their peaks in the same place and their troughs in the same place and this means that when something sees the maximum field it is seeing the maximum field of all the bits of energy and therefore all the bits of energy work together. This makes sense very effective at interacting strongly with material which is pretty nice for doing experiments.

Thanks for the question 🙂

Peta