Steve(s)
The Dark Debate, matter and energy, has revived questions on the reverse engineering of GR as it now stands. It is worthy of note that GR is recognized to be an incomplete theory, even Einstein acknowledged so. While the current census argues for red-shifting in an expanding universe, there is also Hoyle who had gracefully bowed out of the socio-politically inspired embrace of 'The Big Bang'. But I think it is only proper to hold the door open for Hoyle's hypothesis that existence is continuously coming into being and that includes the creation of more space, time and energy driving the expansion. The Bondi, Gold, Hoyle continuous creation universe has been calculated to estimate that to match observation, only one hydrogen atom per year would need to condensed in a billion liters of space. That would be highly probabilistic to detect. But it could model as that condensation being a contraction of space but less than the expansion driven by the tension of spacetime being the origin of energy. jrc