Australian astronomers have combined all observations of supernovae ever made to determine that the strength of gravity has remained unchanged over the last nine billion years. Newton’s gravitational constant, known as G, describes the attractive force between two objects, together with the separation between them and their masses. It has been previously suggested that G could have been slowly changing over the 13.8 billion years since the Big Bang. But researchers have now analyzed the light given off by 580 supernova explosions in the nearby and far Universe and have shown that the strength of gravity has not changed.
from Physics News — ScienceDaily http://ift.tt/NPYdLF