I am a year 1 undergrad physics student helping my professor to do some small project. So I have to know basically what she is doing. Yet, the paper about Feshbach molecule is kind of a bit difficult for me to understand. I found some jargons like open channel, close channel... What are these all about? Can anyone explain the concept of it or give me some physical picture cos I am really overwhelmed by jargons that I cannot know what's happening. Also, how can microwave help to change the quantum state of ultra cold molecules and lower their energy? Not sure if it is related to Feshbach resonance or any? Another question, not so important, is that what is optical dipole trap? I kind of know what the trapping is doing, like using the laser to trap the atom gas for evaporative cooling? But what is the principle of optical dipole trap?