Dennis Sullivan’s Work on Dynamics

Before going into Dennis Sullivan’s work on dynamics, we would like to share some of our reminiscences on the remarkable way in which he influenced a huge number of mathematicians, including the two of us. Both while at IHES and at CUNY, Dennis had an office which came with an anteroom. Our impression is that he would spend most of his time in this anteroom, talking about mathematics with whoever he had invited or whoever was around. Quite often while listening to somebody, he would end up giving a new spin or a new interpretation to what they had been saying. Similarly, he would explain what he was working on, trying out new ideas, and also often explaining results of others. Spending time with him was always an incredible experience.