I just finished my master’s degree and I want to do a PhD in a specific multidisciplinary field. So, I started searching for the professors who work in this research area. I worked as a research assistant in a lab in a lower rank school and I was working in the same research area that I was doing. So, I do have an experience with this field and I don’t have to start from scratch (I took this as an advantage for me over other students) Should I start contact professors directly so if they find me a suitable students they can support my application in those top universities (like Stanford, CalTech, UCSD, etc.)? or professors in those top universities already having the best students to choose from and they don’t bother themselves with recruiting from the outside? Another question, in those top universities, can professors get involved in the admission process or at the end it’s just about the admission people and no say for professors on the admission processes no matters that student is good?