Serrin's type Problems in convex cones in Riemannian manifolds
Murilo Araújo, Allan Freitas, Márcio Santos, Joyce Sindeaux
TL;DR
This work extends Serrin-type overdetermined problems to cones in warped product and Euclidean settings. By combining a Pohozaev-type identity with a $P$-function approach and exploiting closed conformal vector fields, it proves rigidity: sector-like domains in convex cones must be metric balls $\Sigma \cap B_r(x_0)$ under natural curvature and compatibility conditions, with explicit radial solutions in model spaces. It also derives soap-bubble-type and Heintze-Karcher inequalities in warped-cone contexts, linking boundary mean curvature, volume, and domain shape. Finally, it analyzes a weighted (drift) Serrin problem in Euclidean cones, obtaining analogous rigidity results for the drift Laplacian with homogeneous weights, including an explicit radial solution $u = r^2 - \frac{|x|^2}{2(n+\alpha)}$, thereby unifying geometric-analytic methods across unweighted and weighted geometries.
Abstract
In this work, we discuss several results concerning Serrin's problem in convex cones in Riemannian manifolds. First, we present a rigidity result for an overdetermined problem in a class of warped products with Ricci curvature bounded below. As a consequence, we obtain a rigidity result for Einstein warped products. Next, we derive a soap bubble result and a Heintze-Karcher inequality that characterize the intersection of geodesic balls with cones in these spaces. Finally, we analyze the analogous ovedetermined problem for the drift Laplacian, where the ambient space is a cone in the Euclidean space.
