A New 3-dimeiisional Curvature Integral Formula for PL-manifolds of Non-positive Curvature

摘要

In this paper, we derive a new curvature integral formula for 3-dimensional piecewise linear manifolds with singularities. Among other things, we also present a sharp isoperimetric inequality for 3-dimensional PL-manifolds of non-positive curvature by using this new curvature integral formula.