I have participated as a lecturer in a summer school in Nordita in Stockholm. It was really a pleasure to go back to Sweden and to Nordita after a few years, last time I was there I was a postdoc. I really enjoyed the atmosphere of the school, thank in particular to Ivan Khaymovic for all the effort he put in. Lectures were very good and enternaining, I did my best to stay at the level! You can find the videos online here.