paper

Gradient Einstein-type warped products: rigidity, existence and nonexistence results via a nonlinear PDE

arXiv:2407.10337 · doi:10.1016/j.na.2025.113759

Abstract

We establish the necessary and sufficient conditions for constructing gradient Einstein-type warped metrics. One of these conditions leads us to a general Lichnerowicz equation with analytic and geometric coefficients for this class of metrics on the space of warping functions. In this way, we prove gradient estimates for positive solutions of a nonlinear elliptic differential equation on a complete Riemannian manifold with associated Bakry-Émery Ricci tensor bounded from below. As an application, we provide nonexistence and rigidity results for a large class of gradient Einstein-type warped metrics. Furthermore, we show how to construct gradient Einstein-type warped metrics, and then we give explicit examples which are not only meaningful in their own right, but also help to justify our results.

28 pages. Nonlinear Analysis, volume 255, June 2025, 113759

Gradient Einstein-type warped products: rigidity, existence and nonexistence results via a nonlinear PDE · wovepaper