Title: The curvature estimates for sum type of Hessian equations
Abstract: In this talk, we will introduce a new type of Hessian equation, sum type equation. We will generalize the similar concavity appearing in sigma Hessian equations. We also use these concavity to obtain curvature estimates for right hand side depending on the gradient term. These estimates also can be used to discuss the existence results of prescribe curvature problems.