A semiclassical singularity theorem

Abstract Quantum fields do not satisfy the pointwise energy conditions that are assumed in original singularity theorems of Penrose and Hawking. Accordingly, semiclassical quantum gravity lies outside their scope. Although a number have been derived under weakened conditions, none is directly from field theory. Here, we employ inequality satisfied by quantized minimally coupled linear scalar to derive theorem valid gravity. By considering toy cosmological model, show our result predicts timelike geodesic incompleteness on plausible timescales with reasonable at spacelike Cauchy surface.