Bill S, you might want to keep in mind that space is definitely not solid. Remember that it stretches wherever there is mass. Remember black holes? They cause a huge distortion of space. So it has a lot of give to it and can easily be stretched by whatever it is that is causing it to expand. So there is no reason to assume that there is anything being added to cause the expansion of the universe. It is just space stretching, like the balloon in the analogy.

Bill Gill

C is not the speed of light in a vacuum.
C is the universal speed limit.