Has the universe always been flat?
Hello Dr Chris. Firstly thanks for excellent programs. Have been following them for the last 2-3 years via podcast (thanks technology) and find them both informative and amusing.
The flatness of universe is conditioned by the density, and Omega is measured as one = Flat. I have understood that measurements on background radiation indicate that it has always been flat. BUT, since universe is expanding, I gather that the density is getting lower, and was higher. Does this not speak against that universe always has been flat and always will be?