Here's something I can never get my head around, no matter how hard I try. As you look out in space, you look back in time. Fine. No problems yet. Further back in time, the universe was smaller.....or at least things were closer together. Hmmm......hold on just a minute. We have a problem......at least I do and I doubt I'm the only one with it. As you look outwards......the volume of space becomes larger, not smaller. The further out you look, the larger the apparent volume becomes for each similar increase in distance.....and yet, we're told that the universe was actually much SMALLER when the light from those objects was emitted. Now I fully understand how it would be the case that further away the expansion would appear to get greater and greater. That should solve the problem ! But....that's not the real issue. It's a bit trickier than that. My problem is that I can't square this up with the angular size of objects. If the apparent expansion increases exponentially with distance, then there oughtn't to be a linear correlation between distance and size ! In other words......a galaxy 10 billion light years away should not simply appear to be half the size of one the same size at 5 billion light years. If the increase in expansion with distance is the answer to the 'volume' problem, then surely distant galaxies ought to appear larger than their true apparent size at that distance. Yet I've never read anything that suggests other than a linear decrease in angular size proportional to distance.