Maxim Kontsevich (IHES) was on "BPS counting as hyperkaehler metric".
He started from axioms, its background physics and mathematics such as Donaldson-Thomas, quiver cluster algebras, collapsing hyperkaehler geometry, geometric Langlands and classical integrable systems (Hitchin system and Seiberg-Witten theory).
Today was the end of the joint meeting of Japan and France.
