Gradient estimate of a Poisson equation under the almost Ricci solitons.

In this paper, we consider an n-dimensional manifold M n endowed with an almost Bakry–Émery Ricci curvature and study a special case of gradient estimate for the positive solutions of Δ u − X. u = f , for a smooth function f and a smooth vector field X under the almost Ricci solitons condition. [ABSTRACT FROM AUTHOR]