My research is on Gromov-Witten/Donaldson-Thomas theory, Calabi-Yau geometries and mathematical aspects of String theory. Recently, together with collaborators, I have studied and proved the modularity property of DT invariants of CY3’s predicted in the famous S-duality modularity conjecture in string theory in many cases. I also work on the interaction between GW/DT theories and Homological projective duality conjecture by Kuznetsov, as well as proving the relation between geometry of Hilbert scheme of singular surfaces and quantum topology of higher dimensional knots, using representation theory and algebraic geometric techniques.