Integral pinched shrinking Ricci solitons

Abstract

We prove that a n-dimensional, 4≤n≤6, compact gradient shrinking Ricci soliton satisfying a Ln/2-pinching condition is isometric to a quotient of the round Sn. The proof relies mainly on sharp algebraic curvature estimates, the Yamabe–Sobolev inequality and an improved rigidity result for integral pinched Einstein metrics.