Recently I cam across a question posted by a YEC regarding stars and older events in our universe. Here it is followed by my brief answer.
Now I am no astrophysicist, but I do know that science pretty well agrees on the big bang. Therefore the oldest event in the universe is everything originating at the same point.
It is said when we look deeper into space we see older events. Yet, how does that account for the older events happening closer together since the universe is in fact expanding with time? And the older you get the more compressed everything becomes. Is this not true for time as well?
Now I am no astrophysicist either but from what I know, space time like a 3 dimensional grid (actually in theory it is 4 dimensional). FYI, the expansion is not at a consistent rate throughout history. Light as you know, the further it goes from the source, the more it scatters. But also remember that light is both wave and a particle. And that there is a lot of matter in the universe which affects light because of gravity.
Now, the expansion of the universe is happening, we know that. But why is it happening and what it really means to expand?
Consider a stick of gum and put four small objects on it, two objects on either ends, call them group L1 and group L2, mark their position and then stretch the gum. You will see that the distance between group L1 and L2 on either sides of the gum increased from each other but their location on the gum itself hasn’t changed at all, it is the same. The whole gum has expanded.
The same way, the universe expanded, and the expansion which is happening now is because of inertia of the Bigbang. But there is matter in the universe and there is gravity present so the bodies which get closer together, bond with gravity and thus they remain at the same distance at which they bonded. It is simply that their space, like in the gum example, is being stretched but because of their gravitation bond they are not expanding away from each other.
Meaning L1 and L2 moved apart but the two bodies in L2 remained bonded to each other while expanding away from L1 altogether.
Bodies which gravitate towards each other are released from the inertia effect of the big bang therefore they stay with each other because of the gravity in between them. This is the precise reason why the Andromeda galaxy is not moving away but in fact moving towards the milky way galaxy, because of the gravitational force present.
I have oversimplified it but that is the basic thing.