The observable universe is what we see. We cannot measure what we cannot see. Hubble allowed our human eyes astronomical capacities. So, as Dr. Robert Lanza claims, WE are the creators of the universe, because we expand it to the extent our vision reaches. THAT would account for the younger galaxies the farthest away, and most numerous, and the oldest, right next to us.
By the way, there was NO space before the Big Bang. that is any space that can be perceived. Space is the entity created when objects move away from each other, NOT caused by gravity, but by the repulsive force.
As for the center of the universe. . . . . .look in the mirror!!