Hello fellow physicists, I am in need of some advice. I have just recently begun the voyage of a PhD in theoretical physics - with emphasis on Stochastic processes. My undergraduate degree had a lot to do with theoretical physics, but my MSc focus mainly on a different field - Astronomy - and I did a lot of data processing with minimal analytical work. Now I have entered my newly found PhD which is heavily based on courses I had done 2 years prior. I feel extremely rusty and I am not sure how to make meaningful headway with my degree. Any advice from those in a similar situation or been through the same thing?