No gas, no light, no molecules or matter of any kind but it must be "something" or else how could it contain our universe? I see your point. Mind boggling indeed.

My brain can't handle these types of abstract questions. I had a Physics professor that once started to talk about black holes, worm holes, etc. Fascinating but really my brain wanted to shutdown due to overload...cannot compute...(you have to read that last part in your robot voice)