Early univer object detection - physics grad or above plz?

These are difficult things to understand, and here's a further complication. In addition to the expansion of space itself which creates the red shift, the constancy of the speed of light is different than you might imagine. You have to understand a little about relativity. Light is the speed limit of the universe (at least as we understand it in clical physics.) This means just that. Here's a thought problem for you. You leave earth at 3/4 of the speed of light. A sister ship leaves at the same time going in the opposite direction at 3/4 of the speed of light. Can you communicate with that sister ship? It would seem that the separation distance between the two ships is increasing faster than the speed of light, but is it? In fact you can communicate, and here's the proof. You would have to agree that either ship can still communicate with earth, and that earth can communicate with either ship. Since that is true, it means they communicate with each other! The speed of light is not additive. The edge of the universe, which is a relative thing, is the point at which from your own perspective space is expanding at the speed of light. When an astronomer says that something is 10 billion light years away, he is measuring the red shift in real time. It would probably be better to say that the light coming from that object has covered 10 billion light years of space. Does that mean the object is now 20 billion light years away? No. Something that distance by the way, would have an enormous red shift and be retreating at a significant percentage of the speed of light.