Thread: What is a lapse function View Single Post
 Recognitions: Science Advisor GR as a 4D geometrical theory involves equations that relate the 4D spacetime metric and matter. GR can be reformulated as a 3D theory with time evolution, provided spacetime topology isn't weird. The lapse is a function that appears in the 3+1 version. http://arxiv.org/abs/gr-qc/0703035