Sijue Wu (University of Michaigan) On 2-d gravity water waves with angled crests Abstract: In this talk, I will present our recent work on 2-D gravity water waves. We construct an energy functional $E$, that allows for angled crests in the interface, and we show that for any smooth initial data, the unique solution of the 2d water wave system remains smooth so long as $E$ remains finite, and we show that for any initial data satisfying $E(0)<\infty$, there is $T>0$, depending only on $E(0)$, such that the water wave system is solvable for time $t\in [0, T]$.